title: Sean Patrick Maloney

text: In 1991, Maloney began working on Bill Clinton's first campaign for president as deputy to chief scheduler Susan Thomases. In Clinton's 1996 reelection campaign Maloney worked as Director of Surrogate Travel. After Clinton was reelected, Maloney was offered a position in the White House staff and served as a senior advisor and White House Staff Secretary from 1999 to 2000, among the youngest to serve in that capacity. At a campaign event Clinton said that Maloney worked closely with him.


title: Sean Patrick Maloney

text: Following the killing of gay University of Wyoming student Matthew Shepard, Maloney was one of two representatives Clinton sent to his funeral. In an article about the event, a newspaper noted that Maloney often called himself "the highest-ranking openly homosexual man on the White House staff".


title: Sean Patrick Maloney

text: Maloney ran for the Democratic nomination for New York Attorney General in 2006. According to "Gay City News," his "competitive fundraising and wide travels across the state during the past year have impressed many party professionals with the seriousness of his run." During the campaign, Maloney was endorsed by the New-York-state-based gay rights organization Empire State Pride Agenda and Karen Burstein, the first lesbian to run for attorney general, in 1994.


title: Sean Patrick Maloney

text: Consistently polling in the single digits, Maloney was offered a chance to run for the office on the Liberal Party ticket but declined, saying he would support whoever won the Democratic nomination. Maloney finished third in the September 12 primary, with 9.4% of the vote. Former U.S. Secretary of Housing and Urban Development Andrew Cuomo won. In his concession speech, Maloney said, "[T]his day may not be the outcome we hope, but I make you a promise that there will be another day."


title: Sean Patrick Maloney

text: Maloney joined Governor Eliot Spitzer's administration in January 2007 as First Deputy Secretary under top adviser Rich Baum.


title: Sean Patrick Maloney

text: The Eliot Spitzer political surveillance controversy (popularly known as "Troopergate") broke out on July 23, 2007, when Cuomo's office admonished Spitzer's administration for ordering the State Police to create special records of Senate Majority Leader Joseph Bruno's whereabouts when he traveled with police escorts in New York City. A "New York Times" editorial suggested that Maloney might have been involved by withholding emails during the investigation, and the "Times" endorsed Maloney's 2012 election opponent because of its concerns about Maloney's handling of the investigation. "The Wall Street Journal" wrote in July 2012, "[G]enerally, those involved in the investigation on both sides defend Mr. Maloney's conduct. Mr. Cuomo's chief of staff at the time, Steve Cohen, called the idea that Mr. Maloney got in the way of the Attorney General's inquiry 'misinformed to the point of being laughable.'"


title: Sean Patrick Maloney

text: Maloney continued in the same role as a top adviser to Governor David Paterson's administration under his top adviser, Charles O'Byrne. While working for Paterson, Maloney worked on Paterson's effort to increase state aid to education. On December 3, 2008, Maloney announced that he would leave Paterson's office to join the law firm Kirkland & Ellis.


title: Sean Patrick Maloney

text: From 2000 to 2003, Maloney served as chief operating officer of Kiodex, Inc. He was a senior attorney at the law firm Willkie Farr & Gallagher, during which time he represented the Matthew Shepard Foundation. Maloney became a partner in the law firm of Kirkland & Ellis LLP in 2009. In March 2011 he joined the law firm Orrick, Herrington & Sutcliffe as a partner.


title: Sean Patrick Maloney

text: In March 2012, Maloney announced his intention to run for Congress in the 18th district. The district had previously been the 19th, represented by freshman Republican Nan Hayworth. Maloney won the Democratic primary on June 26 with 48% of the vote against four other challengers. In addition to the Democratic Party line, Maloney also ran on the Working Families Party ticket with New York's fusion voting.


title: Sean Patrick Maloney

text: Maloney ran for reelection in 2014, again facing Hayworth. He was a member of the Democratic Congressional Campaign Committee's Frontline Program, designed to help protect vulnerable Democratic incumbents in the 2014 election. Maloney lost the Independence Party primary to Hayworth, but defeated her in the general election by under 3,000 votes, with 84,415 votes (47.58%) to Hayworth's 81,625 (46.01%).


title: Sean Patrick Maloney

text: Maloney ran for reelection in 2016. Fellow Democrat Diana Hird announced her intention to challenge him in the primary election on June 28, 2016, but failed to obtain the necessary number of signatures and file a petition to get on the ballot in time. Maloney handily defeated Republican Phil Oliva, with 162,060 votes (55.6%) to Oliva's 129,369 (44.4%).


title: Sean Patrick Maloney

text: In June 2018, Maloney became the Democratic nominee for reelection to the House. He was also a candidate for the Democratic nomination for attorney general of New York but lost the primary. He had said that, had he won the primary, he would have run for attorney general and relinquished the nomination for the House.


title: Sean Patrick Maloney

text: Maloney was reelected in 2020, with 54.8% of the vote to Republican nominee Chele Farley's 43.2%. On the day Maloney began his new term in Congress, January 3, 2021, he became chair of the Democratic Congressional Campaign Committee.


title: Sean Patrick Maloney

text: On January 3, 2013, Maloney was sworn into the 113th United States Congress. On his second day in office, he spoke on the House floor, criticizing a delay in federal Hurricane Sandy aid and urging House Speaker John Boehner and his colleagues to pass an aid package.


title: Sean Patrick Maloney

text: After joining the "No Labels" Problem Solvers Caucus, Maloney supported the "No Budget, No Pay Act of 2013". Leading up to the 2013 government shutdown, he faced criticism for voting with Republicans to pass a budget that included provisions delaying the implementation of the Patient Protection and Affordable Care Act. His vote drew the ire of LGBT groups, some accusing him of being a "Democrat In Name Only" ("DINO"). He has been an outspoken critic of sequestration and the harmful effects it would have on the United States Military Academy at West Point, and he sent President Barack Obama and Secretary of Defense Chuck Hagel a letter asking for flexibility in his district. During the shutdown Maloney requested that his pay be withheld in solidarity with federal workers.


title: Sean Patrick Maloney

text: In April of his first year in office, Maloney introduced the Creating Reliability for Our Producers Act, the Dam Safety Act, and the Disabled Veterans Red Tape Reduction Act. In October 2013, the House passed the Disabled Veterans Red Tape Reduction Act with near unanimous support. The bill would allow disabled veterans to have their medical examinations performed by physicians outside the Veterans Affairs system.


title: Sean Patrick Maloney

text: In July 2013, Maloney voted against the Farm Bill. The bill failed in the House due largely to the votes of eight Democratic House members who joined the Republican majority.


title: Sean Patrick Maloney

text: On banking issues, Maloney voted in 2014 to repeal the section of Dodd-Frank that would prevent bank bailouts by the public. He voted for the Economic Growth, Regulatory Relief, and Consumer Protection Act in 2018; Elizabeth Warren nicknamed this bill the "Bank Lobbyist Act". Maloney called one opponent's characterization of the latter vote "unhinged", which earned him a rebuke for making remarks that could be considered sexist.


title: Sean Patrick Maloney

text: An issue in Maloney's first campaign for Congress was whether the candidates would vote to repeal the Defense of Marriage Act (DOMA); Hayworth was considered more progressive on gay rights than most Republicans, but did not explicitly say whether she would vote to repeal, saying her belief that the New York law allowing same-sex marriage made it a settled issue, for which Maloney criticized her. After the Supreme Court struck down provisions of DOMA, Maloney said at a press conference that he was "no longer seen as less-than in the eyes of my country", having previously faced discrimination in the House, with his partner not eligible for benefits while members' opposite-sex partners were.


title: Sean Patrick Maloney

text: On April 10, 2014, Maloney introduced the Human Trafficking Prevention Act (H.R. 4449; 113th Congress), a bill that would require regular training and briefings for some federal government personnel to raise awareness of human trafficking and help employees spot cases of it. The bill passed the House on July 23, 2014.


title: Sean Patrick Maloney

text: In July 2014, the FAA began an investigation into whether unmanned aircraft used for Maloney's wedding violated the agency's ban on drone flights. A spokesman for Maloney, who is a member of the House Transportation and Infrastructure Committee's aviation subcommittee, which oversees the FAA, acknowledged that drones were hired.


title: Sean Patrick Maloney

text: Maloney positioned himself as an opponent of President Donald Trump and his agenda, voting in support of that agenda 23.3% of the time as of December 2019. When that number was initially higher, he referred to that statistic as a "bullshit metric".


title: Sean Patrick Maloney

text: In 2021, Maloney became the first openly gay person to be elected chair of the Democratic Congressional Campaign Committee.


title: Sean Patrick Maloney

text: In 2022, Maloney ran for reelection in a different congressional district, New York's 17th, and narrowly lost the general election to Republican Mike Lawler.


title: Sean Patrick Maloney

text: Maloney has been with his husband, Randy Florke, since 1992; they met in New York City, where Maloney was helping plan the Democratic National Convention. Florke is an interior decorator who has been featured in "O, The Oprah Magazine".


title: Sean Patrick Maloney

text: Maloney and Florke became engaged on December 25, 2013. They married in Cold Spring, New York, on June 21, 2014. Maloney became the second member of Congress to legally marry his same-sex partner while in office, the first being former Massachusetts Congressman Barney Frank in 2012.


title: Jason Mitchell

text: Jason Mitchell (born January 5, 1987) is an American actor. Mitchell started his career acting in minor roles in films such as the action-thriller "Contraband" (2012), and the neo-noir "Broken City" (2013). He is best known for portraying rapper Eazy-E in the 2015 biopic "Straight Outta Compton". The film is considered his career breakthrough, for which he received numerous award nominations including the Screen Actors Guild Award for Outstanding Ensemble Cast in a Motion Picture. Mitchell has also appeared in the Key and Peele comedy film "Keanu" (2016), the Netflix film "Barry" (2016), James Franco's "The Disaster Artist" (2017), and the blockbuster "" (2017). He has also appeared in critically acclaimed film such as Kathryn Bigelow's crime drama "Detroit" (2017), Dee Rees' historical drama "Mudbound" (2017) and Janicza Bravo's black comedy "Zola" (2021).


title: Jason Mitchell

text: Mitchell is also known for his television roles, making guest appearances in the Amazon Studios limited series "Philip K. Dick's Electric Dreams" (2018), Alan Yang's dark comedy series "Forever" acting alongside Hong Chau. Starting in 2018 he was cast in Lena Waithe's Showtime series "The Chi" until 2019 when he was accused of multiple allegations of misconduct and subsequently fired from the show. He was also dropped by several talent agencies.


title: Jason Mitchell

text: Mitchell had his film debut in 2011 as a 7-Eleven cashier in the crime film "Texas Killing Fields". He continued acting in minor roles such as the action-thriller "Contraband" (2012) starring Mark Wahlberg, and the political neo-noir "Broken City" (2013) starring Russell Crowe and Wahlberg.


title: Jason Mitchell

text: In 2014, Mitchell made his film breakthrough when he was cast as Compton rapper Eazy-E in the F. Gary Gray directed biopic "Straight Outta Compton", with his performance being met with significant praise by critics. He received multiple awards nominations including the Screen Actors Guild Award for Outstanding Performance by a Cast in a Motion Picture. In 2016, he appeared in "Keanu", which starred Keegan-Michael Key and Jordan Peele, and in the Netflix biopic about Barack Obama.


title: Jason Mitchell

text: In 2017 starred as a Vietnam War officer in the blockbuster monster movie, "". That same year he also appeared in James Franco's comedy film "The Disaster Artist". He also starred in two critically acclaimed films, Kathryn Bigelow's crime drama "Detroit" starring John Boyega, Kaitlyn Dever, and Will Poulter and Dee Rees' historical drama "Mudbound". For the later he received the Independent Spirit Robert Altman Award and the Gotham Award for Outstanding Ensemble Performance along the cast which included Carey Mulligan, Jason Clarke, Jonathan Banks, and Mary J. Blige. Mitchell also received his second Screen Actors Guild Award for Outstanding Ensemble Cast in a Motion Picture nomination.


title: Jason Mitchell

text: Michell has also made appearances in television including in the Amazon Studios limited series "Philip K. Dick's Electric Dreams" (2017) where he appeared in the episode, "Kill all Others". He also appeared in the Alan Yang created dark comedy series "Forever" (2018) starring in the episode "Andre and Sarah", playing Andre with Hong Chau playing Sarah. The episode was critically acclaimed for its storytelling and performances. In 2018, Mitchell starred in the Lena Waithe's Showtime drama series "The Chi", but did not return for a third season due to his misconduct allegations.


title: Jason Mitchell

text: In May 2019, Mitchell was fired from "The Chi" when showrunners Ayanna Floyd Davis and co-star Tiffany Boone accused him of sexual misconduct. Boone was among many actresses who "made repeated complaints of sexual harassment" against Mitchell and said she felt "unsafe" around him.


title: Jason Mitchell

text: While creator and showrunner Lena Waithe claimed that Mitchell had never acted inappropriately towards her, she knew of the allegations after filming had wrapped on season one of "The Chi". Waithe reportedly sought preemptive and corrective measures to handle the situation. She stated that there had been extensive sexual harassment training on set and that she confronted Mitchell about the allegations by saying, "There was definitely a conversation where I called him and got really real". Waithe alleged the harassment and misconduct allegations continued into season two despite the corrective measures taken.


title: Jason Mitchell

text: Mitchell denied the multiple allegations of sexual harassment and misconduct against him saying, "I'm all for the Me Too movement...but I think in this situation, [Floyd Davis] tried to use it as a really, really ugly weapon". Mitchell was subsequently fired from the Netflix film "Desperados", and was dropped by United Talent Agency and Authentic Talent & Literary Management.


title: Jason Mitchell

text: Mitchell was arrested on April 22, 2020, on multiple counts, including "possession of a controlled substance with intent to distribute and possession of a firearm by a felon." Officers searched his SUV and found about 2 pounds of marijuana with a bag of 1,300 dosage units of Ecstasy. Deputies also found an AK-47 firearm and a Glock 9mm pistol with extended magazines. Mitchell was released after posting a $150,000 surety bond.


title: Mathieu Flamini

text: Mathieu Pierre Flamini (born 7 March 1984) is a French former professional footballer and environmental entrepreneur. A midfielder, he has played for French side Marseille, English sides Arsenal and Crystal Palace, Italian side Milan and Spanish side Getafe. At international level, he has been capped by the France national team on three occasions.


title: Mathieu Flamini

text: Flamini is a co-founder of GF Biochemicals, the first company in the world able to mass-produce levulinic acid.


title: Mathieu Flamini

text: Born in Marseille, Flamini was a youth team player for his local professional club Marseille. He made his debut for the senior team on 20 December 2003 in the 1–0 victory over Toulouse. He impressed the team as a hardworking midfield player and played 14 times for the club. However, it was his performances in Marseille’s UEFA Cup campaign that brought him to the attention of the football world, including the 2–0 semi-final victory over Newcastle United. He then started in the Final in Gothenburg, a match Spanish club Valencia won 2–0. Due to his age, however, Marseille was later unable to offer him a long-term professional contract.


title: Mathieu Flamini

text: On 23 July 2004, Flamini signed a professional contract for English club Arsenal, rejecting Marseille's long-term senior contract offer to which he had already verbally agreed. Soon after the incident, then-Marseille manager José Anigo stated, "This is a beautiful treason. He used me." Arsenal were eventually ordered by The Dispute Resolution Chamber of FIFA to pay Marseille a compensation fee of €480 000 for Flamini.


title: Mathieu Flamini

text: Flamini made his Arsenal debut in the 1–4 win at Everton on 15 August 2004. In his first season, he was typically used as a utility player, starting only nine games but used as a substitute in 12. The following season saw him filling in for a number of injured players, but again unable to command a first team place in his favoured position. He scored his first Arsenal goal on 11 May 2005 in a 7–0 home win against Everton, scoring the seventh goal, the team's last-ever goal scored in their traditional red and white kit at Highbury.


title: Mathieu Flamini

text: In the 2006–07 season, Flamini scored the winning goal against Dinamo Zagreb in the qualifying stages of the UEFA Champions League. He also scored important goals against Chelsea, Blackburn Rovers and Liverpool in the Premier League. Despite these important goals, however, he remained unsatisfied with his "utility player" role at the club and in April 2007, he admitted that he would most likely be leaving Arsenal in the summer. Flamini, however, turned down a proposed £3m move to Birmingham City and remained with the team.


title: Mathieu Flamini

text: Flamini started in central midfield for Arsenal's first match of the 2007–08 Premier League season due to the absence of Gilberto Silva and Abou Diaby. During Arsenal's 2007–08 campaign, he struck up a strong partnership with Cesc Fàbregas, keeping Gilberto out of the starting XI with displays widely regarded by Arsenal fans as a vast improvement on those during his previous years at the club. Flamini enjoyed a generally good rapport with Arsenal's fans, who provided him with his own song, an adaptation of the theme tune to British television programme "The Sweeney". On 29 January 2008, he scored an extraordinary strike in Arsenal's 3–0 win over Newcastle United in the Premier League. He played on 8 April 2008, a UEFA Champions League match in which Arsenal were knocked out by English rival Liverpool. After the match, he was reported injured and it proved to be his last match for Arsenal. In April 2009, he stated in an interview that he is still an Arsenal fan and that he has no hard feelings towards the club: "Arsenal are in my heart and they will be in my heart for ever," he said. "I will always be an Arsenal fan and leaving was not easy."


title: Mathieu Flamini

text: Flamini signed a contract with Italian club Milan on 5 May 2008. Flamini wore the number 84 on his shirt to represent his year of birth.


title: Mathieu Flamini

text: He made his Serie A debut on 30 August 2008 in a 2–1 loss to Bologna. Initially, Flamini did not enjoy the number of starts or appearances for the Italian team, and was regarded as a utility player at Milan. Nevertheless, injuries to other players and his consistent good form helped him to cement a starting place at San Siro. With Milan failing to find a stable defence and a lack of a fit, consistent and reliable right back, Gianluca Zambrotta was switched to the left flank to help Flamini develop as a tenacious right back. After stating that his preferred position is in the midfield, Milan re-deployed him as a defensive midfielder.


title: Mathieu Flamini

text: Flamini saw limited playing time towards the end of 2009–10 season due to the great form of club captain Massimo Ambrosini. In the following season, Flamini became an important asset of the team that would win its 18th "scudetto", playing many games as starter and scoring two goals against Bari and Bologna, respectively. After playing as a rotation role in the 2010–11 season, he injured himself in a pre-season training session, suffering a serious knee injury which required an operation. Flamini spent the entire 2011–12 season out.


title: Mathieu Flamini

text: On 20 June 2012, it was confirmed by the club that he had left following the expiration of his contract, as they had ended negotiations with the player, and so he became a free agent. Two weeks later, Flamini and Adriano Galliani reached a new agreement for a one-year contract, with the Frenchman taking a significant cut in his wages. On 7 April 2013, Flamini scored his first goal of the season, and Milan's second of the game, in a 2–2 draw against Fiorentina.


title: Mathieu Flamini

text: Flamini began training with Arsenal midway in early August, with the reason to "solely maintain fitness" with a view to signing for a club in England. Immediately it sparked media attention with claims rising that he would soon sign for Arsenal, but these reports were shunned by many journalists, pointing out that many other ex-Arsenal players had returned to train with Arsenal, including club legends Robert Pires and Thierry Henry.


title: Mathieu Flamini

text: Flamini, however, did indeed sign for Arsenal on 29 August 2013 and became Arsenal's second acquisition of the summer, after Yaya Sanogo. He made his returning debut on 1 September at Emirates Stadium against Tottenham Hotspur, coming on for Jack Wilshere and helping the team secure a 1–0 win. His performances after signing were lauded by both critics and fans alike, and had featured in all of Arsenal's Premier League, Football League Cup and European games since, with many seeing his signing, and his combative style of play, as one of the key reasons for Arsenal's excellent early season form. He scored his first goal in his second spell at Arsenal on 30 November, the second in a 0–3 away win at Cardiff City. He has also scored in a crucial 1–1 draw against Manchester City after a run of bad form from Arsenal, helping the club rejuvenate and achieve an eventual top four league finish. At the start of Arsenal's 2013–14 FA Cup run, Flamini expressed his desire to win the Cup, having been left out of the squad when Arsenal won the 2005 FA Cup Final. Arsenal went on to win the tournament, though Flamini was an unused substitute in the Final, also remaining on the substitutes' bench when Arsenal repeated the feat, becoming FA Cup champions again in 2015.


title: Mathieu Flamini

text: On 23 September 2015, Flamini earned his first start of the 2015–16 season in the Football League Cup third round tie against Tottenham Hotspur. He scored both of Arsenal's goals with a Man of the Match performance.


title: Mathieu Flamini

text: Flamini signed as a free-agent for Crystal Palace on 8 September 2016. He was released by the club at the end of the 2016–17 season.


title: Mathieu Flamini

text: On 2 February 2018, Flamini signed for Getafe on a free transfer. He made eight appearances in La Liga before leaving the club at the end of the season.


title: Mathieu Flamini

text: Flamini accepted his first call up to France by coach Raymond Domenech for a friendly against Argentina at the Stade de France on 7 February 2007 after Jérémy Toulalan was ruled out due to injury. He later made his international debut in a friendly against Morocco on 16 November 2007 as a substitute.


title: Mathieu Flamini

text: A combative, energetic, tactically intelligent, and tenacious midfielder, according to Arsenal manager Arsène Wenger, Flamini is a player with a fantastic work rate, good ball-winning ability and great mentality; he can play anywhere across midfield, in the centre as a box-to-box or defensive midfielder, or on either flank as a cover at full-back.


title: Mathieu Flamini

text: Flamini is a partner of GF Biochemicals, a leading global producer of levulinic acid and derivatives. He has stated that “we founded GFBiochemicals with the ambition of finding sustainable alternatives to oil-based products”. Levulinic acid includes grass or woodchips, and can be used in plastics, solvents, fuels and the pharmaceutical industry. Levulinic acid has been identified by the U.S. Department of Energy as one of the 12 molecules that can help unlock a “greener” world.


title: Mathieu Flamini

text: In addition to GFBiochemicals’ established presence in the Netherlands and headquarters in Italy, Flamini has named China and Brazil as potential new markets for expansion.


title: Mathieu Flamini

text: In 2016, GFBiochemicals fully controls the Segetis, the leading producer of levulinic acid derivatives, in a move towards downstream integration. Segitis was previously owned by Sabic, DSM, and Kosla Ventures, among other entities, and has invested in R&D over the past decade. In 2017, GFBiochemicals announced that it will build a cellulosic biorefinery in the US, in partnership with biotech company American Process.


title: Mathieu Flamini

text: Flamini was also part of the team that created BIOCIRCE (Bioeconomy in the Circular economy), Europe’s first master's degree dedicated to promoting bioeconomy education. It was launched in collaboration with Italian bank Intesa Sanpaolo, Novamont (a producer of bioplastics), and the Universities of Naples, Torino, Milano Bicocca and Bologna.


title: Mathieu Flamini

text: In addition, Flamini co-founded The BioJournal the world’s first e-magazine devoted entirely to the bio world and eco-sustainability and managed by Italian environmental journalist Mario Bonaccorso.


title: Mathieu Flamini

text: Flamini is also part of the Environmental Excellence Committee for the candidature of Paris as the location for the 2024 Summer Olympics.


title: Soldering

text: Soldering (; ) is a process in which two or more items are joined by melting and putting a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Unlike welding, soldering does not involve melting the work pieces. In brazing, the work piece metal also does not melt, but the filler metal is one that melts at a higher temperature than in soldering. In the past, nearly all solders contained lead, but environmental and health concerns have increasingly dictated use of lead-free alloys for electronics and plumbing purposes.


title: Soldering

text: There is evidence that soldering was employed as early as 5,000 years ago in Mesopotamia. Soldering and brazing are thought to have originated very early in the history of metal-working, probably before 4000 BC. Sumerian swords from were assembled using hard soldering.


title: Soldering

text: Soldering was historically used to make jewelry, cookware and cooking tools, assembling stained glass, as well as other uses.


title: Soldering

text: Soldering is used in plumbing, electronics, and metalwork from flashing to jewelry and musical instruments.


title: Soldering

text: Soldering provides reasonably permanent but reversible connections between copper pipes in plumbing systems as well as joints in sheet metal objects such as food cans, roof flashing, rain gutters and automobile radiators.


title: Soldering

text: Jewelry components, machine tools and some refrigeration and plumbing components are often assembled and repaired by the higher temperature silver soldering process. Small mechanical parts are often soldered or brazed as well. Soldering is also used to join lead came and copper foil in stained glass work.


title: Soldering

text: Electronic soldering connects electrical wiring to devices, and electronic components to printed circuit boards. Electronic connections may be hand-soldered with a soldering iron. Automated methods such as wave soldering or use of ovens can make many joints on a complex circuit board in one operation, vastly reducing production cost of electronic devices.


title: Soldering

text: Musical instruments, especially brass and woodwind instruments, use a combination of soldering and brazing in their assembly. Brass bodies are often soldered together, while keywork and braces are most often brazed.


title: Soldering

text: The solderability of a substrate is a measure of the ease with which a soldered joint can be made to that material.


title: Soldering

text: Some metals are easier to solder than others. Copper, zinc, brass, silver and gold are easy. Iron, mild steel and nickel are next in difficulty. Because of their thin, strong oxide films, stainless steel and some aluminium alloys are even more difficult to solder. Titanium, magnesium, cast irons, some high-carbon steels, ceramics, and graphite can be soldered but it involves a process similar to joining carbides: they are first plated with a suitable metallic element that induces interfacial bonding.


title: Soldering

text: Soldering filler materials are available in many different alloys for differing applications. In electronics assembly, the eutectic alloy with 63% tin and 37% lead (or 60/40, which is almost identical in melting point) has been the alloy of choice. Other alloys are used for plumbing, mechanical assembly, and other applications. Some examples of soft-solder are tin-lead for general purposes, tin-zinc for joining aluminium, lead-silver for strength at higher than room temperature, cadmium-silver for strength at high temperatures, zinc-aluminium for aluminium and corrosion resistance, and tin-silver and tin-bismuth for electronics.


title: Soldering

text: A eutectic formulation has advantages when applied to soldering: the liquidus and solidus temperatures are the same, so there is no plastic phase, and it has the lowest possible melting point. Having the lowest possible melting point minimizes heat stress on electronic components during soldering. And, having no plastic phase allows for quicker wetting as the solder heats up, and quicker setup as the solder cools. A non-eutectic formulation must remain still as the temperature drops through the liquidus and solidus temperatures. Any movement during the plastic phase may result in cracks, resulting in an unreliable joint.


title: Soldering

text: Common solder formulations based on tin and lead are listed below. The fraction represent percentage of tin first, then lead, totaling 100%:


title: Soldering

text: For environmental reasons and the introduction of regulations such as the European RoHS (Restriction of Hazardous Substances Directive), lead-free solders are becoming more widely used. They are also suggested anywhere young children may come into contact with (since young children are likely to place things into their mouths), or for outdoor use where rain and other precipitation may wash the lead into the groundwater. Unfortunately, common lead-free solders are not eutectic formulations, melting at around , making it more difficult to create reliable joints with them.


title: Soldering

text: Other common solders include low-temperature formulations (often containing bismuth), which are often used to join previously soldered assemblies without unsoldering earlier connections, and high-temperature formulations (usually containing silver) which are used for high-temperature operation or for first assembly of items which must not become unsoldered during subsequent operations. Alloying silver with other metals changes the melting point, adhesion and wetting characteristics, and tensile strength. Of all the brazing alloys, silver solders have the greatest strength and the broadest applications. Specialty alloys are available with properties such as higher strength, the ability to solder aluminum, better electrical conductivity, and higher corrosion resistance.


title: Soldering

text: The purpose of flux is to facilitate the soldering process. One of the obstacles to a successful solder joint is an impurity at the site of the joint; for example, dirt, oil or oxidation. The impurities can be removed by mechanical cleaning or by chemical means, but the elevated temperatures required to melt the filler metal (the solder) encourages the work piece (and the solder) to re-oxidize. This effect is accelerated as the soldering temperatures increase and can completely prevent the solder from joining to the workpiece. One of the earliest forms of flux was charcoal, which acts as a reducing agent and helps prevent oxidation during the soldering process. Some fluxes go beyond the simple prevention of oxidation and also provide some form of chemical cleaning (corrosion). Many fluxes also act as a wetting agent in the soldering process, reducing the surface tension of the molten solder and causing it to flow and wet the workpieces more easily.


title: Soldering

text: For many years, the most common type of flux used in electronics (soft soldering) was rosin-based, using the rosin from selected pine trees. It was nearly ideal in that it was non-corrosive and non-conductive at normal temperatures but became mildly reactive (corrosive) at elevated soldering temperatures. Plumbing and automotive applications, among others, typically use an acid-based (hydrochloric acid) flux which provides rather aggressive cleaning of the joint. These fluxes cannot be used in electronics because their residues are conductive leading to unintended electrical connections, and because they will eventually dissolve small diameter wires. Citric acid is an excellent water-soluble acid-type flux for copper and electronics but must be washed off afterwards.


title: Soldering

text: Flux performance must be carefully evaluated for best results; a very mild 'no-clean' flux might be perfectly acceptable for production equipment, but not give adequate performance for more variable hand-soldering operations.


title: Soldering

text: Different types of soldering tools are made for specific applications. The required heat can be generated from burning fuel or from an electrically operated heating element. Another method for soldering is to place solder at the locations of joints in the object to be soldered, then heat the entire object in an oven to melt the solder.


title: Soldering

text: The electric soldering iron is widely used for hand-soldering. It can be fitted with a variety of tips, ranging from blunt, to very fine, to chisel heads for hot-cutting plastics rather than soldering. The simplest irons do not have temperature regulation. Small irons rapidly cool when used to solder to, say, a metal chassis, while large irons have tips too cumbersome for working on printed circuit boards (PCBs) and similar fine work. A 25-watt iron will not provide enough heat for large electrical connectors, joining copper roof flashing, or large stained-glass lead came. On the other hand, a 100-watt iron may provide too much heat for PCBs. Temperature-controlled irons have a reserve of power and can maintain temperature over a wide range of work.


title: Soldering

text: The soldering gun heats faster but has a larger and heavier body. Gas-powered irons using a catalytic tip to heat a bit, without flame, are used for portable applications. Hot-air guns and pencils allow rework of component packages which cannot easily be performed with electric irons and guns.


title: Soldering

text: For non-electronic applications, soldering torches use a flame rather than a soldering tip to heat solder. Soldering torches are often powered by butane and are available in sizes ranging from very small butane/oxygen units suitable for very fine but high-temperature jewelry work, to full-size oxy-fuel torches suitable for much larger work such as copper piping. Common multipurpose propane torches, the same kind used for heat-stripping paint and thawing pipes, can be used for soldering pipes and other fairly large objects either with or without a soldering tip attachment; pipes are generally soldered with a torch by directly applying the open flame.


title: Soldering

text: A soldering copper is a tool with a large copper head and a long handle which is heated in a blacksmith's forge fire and used to apply heat to sheet metal for soldering. Typical soldering coppers have heads weighing between one and four pounds. The head provides a large thermal mass to store enough heat for soldering large areas before needing re-heating in the fire; the larger the head, the longer the working time. Historically, soldering coppers were standard tools used in auto bodywork, although body solder has been mostly superseded by spot welding for mechanical connection, and non-metallic fillers for contouring.


title: Soldering

text: Toaster ovens and hand-held infrared lights have been used by hobbyists to replicate production soldering processes on a much smaller scale.


title: Soldering

text: During WW2 and for some time afterwards SOE forces used small pyrotechnic self-soldering joints to make connections for the remote detonation of demolition and sabotage explosives. These consisted of a small copper tube partially filled with solder and a slow-burning pyrotechnic composition wrapped around the tube. The wires to be joined would be inserted into the tube and a small blob of ignition compound allowed the device to be struck like a match to ignite the pyrotechnic and heat the tube for long enough to melt the solder and make the joint.


title: Soldering

text: "Laser soldering" is a technique where a 30–50 W laser is used to melt and solder an electrical connection joint. Diode laser systems based on semiconductor junctions are used for this purpose. Suzanne Jenniches patented laser soldering in 1980.


title: Soldering

text: Wavelengths are typically 808 nm through 980 nm. The beam is delivered via an optical fiber to the workpiece, with fiber diameters 800 µm and smaller. Since the beam out of the end of the fiber diverges rapidly, lenses are used to create a suitable spot size on the workpiece at a suitable working distance. A wire feeder is used to supply solder.


title: Soldering

text: Both lead-tin and silver-tin material can be soldered. Process recipes will differ depending on the alloy composition. For soldering 44-pin chip carriers to a board using soldering preforms, power levels were on the order of 10 watts and solder times approximately 1 second. Low power levels can lead to incomplete wetting and the formation of voids, both of which can weaken the joint.


title: Soldering

text: Induction soldering uses induction heating by high-frequency alternating current in a surrounding copper coil. This induces currents in the part being soldered, which generates heat because of the higher resistance of a joint versus its surrounding metal (resistive heating). These copper coils can be shaped to fit the joint more precisely. A filler metal (solder) is placed between the facing surfaces, and this solder melts at a fairly low temperature. Fluxes are commonly used in induction soldering. This technique is particularly suited to continuously soldering, in which case these coils wrap around a cylinder or a pipe that needs to be soldered.


title: Soldering

text: Fiber focus infrared soldering is technique where many infrared sources are led through fibers, then focused onto a single spot at which the connection is soldered.


title: Soldering

text: Resistance soldering is soldering in which the heat required to flow the solder is created by passing an electric current through the solder. When current is conducted through a resistive material a certain level of heat is generated. By regulating the amount of current conducted and the level of resistance encountered, the amount of heat produced can be predetermined and controlled.


title: Soldering

text: Electrical resistance (usually described as a material's opposition to the flow of an electric current) is used to convert electric energy into thermal energy as an electric current ("I") conducted through a material with resistance ("R") releases power ("P") equal to "P" = "I""R", where "P" is the power measured in watts, "I" is the current measured in amperes and "R" is the resistance measured in ohms.


title: Soldering

text: Resistance soldering is unlike using a conduction iron, where heat is produced within an element and then passed through a thermally conductive tip into the joint area. A cold soldering iron requires time to reach working temperature and must be kept hot between solder joints. Thermal transfer may be inhibited if the tip is not kept properly wetted during use. With resistance soldering an intense heat can be rapidly developed directly within the joint area and in a tightly controlled manner. This allows a faster ramp up to the required solder melt temperature and minimizes thermal travel away from the solder joint, which helps to minimize the potential for thermal damage to materials or components in the surrounding area. Heat is only produced while each joint is being made, making resistance soldering more energy efficient. Resistance soldering equipment, unlike conduction irons, can be used for difficult soldering and brazing applications where significantly higher temperatures may be required. This makes resistance comparable to flame soldering in some situations. When the required temperature can be achieved by either flame or resistance methods the resistance heat is more localized because of direct contact, whereas the flame will spread thus heating a potentially larger area.


title: Soldering

text: Flux-less soldering with aid of conventional soldering iron, ultrasonic soldering iron or specialized solder pot and active solder that contains an active element, most often titanium, zirconium or chromium. The active elements, owing to mechanical activation, react with the surface of the materials generally considered difficult to solder without premetallization. The active solders can be protected against excessive oxidation of their active element by addition of rare-earth elements with higher affinity to oxygen (typically cerium or lanthanum). Another common additive is gallium – usually introduced as a wetting promoter. Mechanical activation, needed for active soldering, can be performed by brushing (for example with use of stainless wire brush or steel spatula) or ultrasonic vibration (20–60 kHz). Active soldering has been shown to effectively bond ceramics, aluminium, titanium, silicon, graphite and carbon nanotube based structures at temperatures lower than 450 °C or use of protective atmosphere.


title: Soldering

text: There are three forms of soldering, each requiring progressively higher temperatures and producing an increasingly stronger joint strength:


title: Soldering

text: The alloy of the filler metal for each type of soldering can be adjusted to modify the melting temperature of the filler. Soldering differs from gluing significantly in that the filler metals directly bond with the surfaces of the workpieces at the junction to form a bond that is both electrically conductive and gas- and liquid-tight.


title: Soldering

text: Soft soldering is characterized by having a melting point of the filler metal below approximately , whereas silver soldering and brazing use higher temperatures, typically requiring a flame or carbon arc torch to achieve the melting of the filler. Soft solder filler metals are typically alloys (often containing lead) that have liquidus temperatures below .


title: Soldering

text: In this soldering process, heat is applied to the parts to be joined, causing the solder to melt and to bond to the workpieces in a surface alloying process called wetting. In stranded wire, the solder is drawn up into the wire between the strands by capillary action in a process called 'wicking'. Capillary action also takes place when the workpieces are very close together or touching. The joint's tensile strength is dependent on the filler metal used; in electrical soldering little tensile strength comes from the added solder which is why it is advised that wires be twisted or folded together before soldering to provide some mechanical strength for a joint. A good solder joint produces an electrically conductive, water- and gas-tight join.


title: Soldering

text: Each type of solder offers advantages and disadvantages. Soft solder is so called because of the soft lead that is its primary ingredient. Soft soldering uses the lowest temperatures (and so thermally stresses components the least) but does not make a strong joint and is unsuitable for mechanical load-bearing applications. It is also unsuitable for high-temperature applications as it loses strength, and eventually melts. Silver soldering, as used by jewelers, machinists and in some plumbing applications, requires the use of a torch or other high-temperature source, and is much stronger than soft soldering. Brazing provides the strongest of the non-welded joints but also requires the hottest temperatures to melt the filler metal, requiring a torch or other high temperature source and darkened goggles to protect the eyes from the bright light produced by the white-hot work. It is often used to repair cast-iron objects, wrought-iron furniture, etc.


title: Soldering

text: Soldering operations can be performed with hand tools, one joint at a time, or "en masse" on a production line. Hand soldering is typically performed with a soldering iron, soldering gun, or a torch, or occasionally a hot-air pencil. Sheetmetal work was traditionally done with "soldering coppers" directly heated by a flame, with sufficient stored heat in the mass of the soldering copper to complete a joint; gas torches (e.g. butane or propane) or electrically heated soldering irons are more convenient. All soldered joints require the same elements of cleaning of the metal parts to be joined, fitting up the joint, heating the parts, applying flux, applying the filler, removing heat and holding the assembly still until the filler metal has completely solidified. Depending on the nature of flux material used and the application, cleaning of the joint may be required after it has cooled.


title: Soldering

text: Each solder alloy has characteristics that work best for certain applications, notably strength and conductivity, and each type of solder and alloy has different melting temperatures. The term "silver solder" denotes the type of solder that is used. Some soft solders are "silver-bearing" alloys used to solder silver-plated items. Lead-based solders should not be used on precious metals because the lead dissolves the metal and disfigures it.


title: Soldering

text: The distinction between soldering and brazing is based on the melting temperature of the filler alloy. A temperature of 450 °C is usually used as a practical demarcation between soldering and brazing. Soft soldering can be done with a heated iron whereas the other methods typically require a higher temperature torch or a furnace to melt the filler metal.


title: Soldering

text: Different equipment is usually required since a soldering iron cannot achieve high enough temperatures for hard soldering or brazing. Brazing filler metal is stronger than silver solder, which is stronger than lead-based soft solder. Brazing solders are formulated primarily for strength, silver solder is used by jewelers to protect the precious metal and by machinists and refrigeration technicians for its tensile strength but lower melting temperature than brazing, and the primary benefit of soft solder is the low temperature used (to prevent heat damage to electronic components and insulation).


title: Soldering

text: Since the joint is produced using a metal with a lower melting temperature than the workpiece, the joint will weaken as the ambient temperature approaches the melting point of the filler metal. For that reason, the higher temperature processes produce joints which are effective at higher temperatures. Brazed connections can be as strong or nearly as strong as the parts they connect, even at elevated temperatures.


title: Soldering

text: "Hard soldering" or "silver soldering" is used to join precious and semi-precious metals such as gold, silver, brass, and copper. The solder is usually described as easy, medium, or hard in reference to its melting temperature, not the strength of the joint. Extra-easy solder contains 56% silver and has a melting point of . Extra-hard solder has 80% silver and melts at . If multiple joints are needed, then the jeweler will start with hard or extra-hard solder and switch to lower-temperature solders for later joints.


title: Soldering

text: Silver solder is somewhat absorbed by the surrounding metal, resulting in a joint that is actually stronger than the metal being joined. The metal being joined must be perfectly flush, as silver solder cannot normally be used as a filler and will not fill gaps.


title: Soldering

text: Another difference between brazing and soldering is how the solder is applied. In brazing, one generally uses rods that are touched to the joint while being heated. With silver soldering, small pieces of solder wire are placed onto the metal prior to heating. A flux, often made of boric acid and denatured alcohol, is used to keep the metal and solder clean and to prevent the solder from moving before it melts.


title: Soldering

text: When silver solder melts, it tends to flow towards the area of greatest heat. Jewelers can somewhat control the direction the solder moves by leading it with a torch; it will even sometimes run straight up along a seam.


title: Soldering

text: A number of solder materials, primarily zinc alloys, are used for soldering aluminium metal and alloys and to a lesser extent steel and zinc. This mechanical soldering is similar to a low temperature brazing operation, in that the mechanical characteristics of the joint are reasonably good and it can be used for structural repairs of those materials.


title: Soldering

text: The American Welding Society defines brazing as using filler metals with melting points over — or, by the traditional definition in the United States, above . Aluminium soldering alloys generally have melting temperatures around . This soldering / brazing operation can use a propane torch heat source.


title: Soldering

text: These materials are often advertised as "aluminium welding", but the process does not involve melting the base metal, and therefore is not properly a weld.


title: Soldering

text: United States Military Standard or MIL-SPEC specification MIL-R-4208 defines one standard for these zinc-based brazing/soldering alloys. A number of products meet this specification. or very similar performance standards.


title: Soldering

text: Copper pipe, or 'tube', is commonly joined by soldering. When applied in a plumbing trade context in the United States, soldering is often referred to as "sweating", and a tubing connection so made is referred to as a "sweated joint".


title: Soldering

text: Outside the United States, "sweating" refers to the joining of flat metallic surfaces by a two step process by which solder is first applied to one surface, then this first piece is placed in position against the second surface and both are re-heated to achieve the desired joint.


title: Soldering

text: Copper tubing conducts heat away much faster than a conventional hand-held soldering iron or gun can provide, so a propane torch is most commonly used to deliver the necessary power; for large tubing sizes and fittings a MAPP-fueled, acetylene-fueled, or propylene-fueled torch is used with atmospheric air as the oxidizer; MAPP/oxygen or acetylene/oxygen are rarely used because the flame temperature is much higher than the melting point of copper. Too much heat destroys the temper of hard-tempered copper tubing, and can burn the flux out of a joint before the solder is added, resulting in a faulty joint. For larger tubing sizes, a torch fitted with various sizes of interchangeable "swirl tips" is employed to deliver the needed heating power. In the hands of a skilled tradesman, the hotter flame of acetylene, MAPP, or propylene allows more joints to be completed per hour without damage to copper tempering.


title: Soldering

text: However, it is possible to use an electrical tool to solder joints in copper pipe sized from . For example, the Antex Pipemaster is recommended for use in tight spaces, when open flames are hazardous, or by do-it-yourself users. The pliers-like tool uses heated fitted jaws that completely encircle the pipe, allowing a joint to be melted in as little as 10 seconds.


title: Soldering

text: Solder fittings, also known as 'capillary fittings', are usually used for copper joints. These fittings are short sections of smooth pipe designed to slide over the outside of the mating tube. Commonly used fittings include for straight connectors, reducers, bends, and tees. There are two types of solder fittings: 'end feed fittings' which contain no solder, and 'solder ring fittings' (also known as Yorkshire fittings), in which there is a ring of solder in a small circular recess inside the fitting.


title: Soldering

text: As with all solder joints, all parts to be joined must be clean and oxide free. Internal and external wire brushes are available for the common pipe and fitting sizes; emery cloth and wire-wool are frequently used as well, although metal wool products are discouraged, as they can contain oil, which would contaminate the joint.


title: Soldering

text: Because of the size of the parts involved, and the high activity and contaminating tendency of the flame, plumbing fluxes are typically much more chemically active, and often more acidic, than electronic fluxes. Because plumbing joints may be done at any angle, even upside down, plumbing fluxes are generally formulated as pastes which stay in place better than liquids. Flux is applied to all surfaces of the joint, inside and out. Flux residues are removed after the joint is complete to prevent erosion and failure of the joint.


title: Soldering

text: Many plumbing solder formulations are available, with different characteristics, such as higher or lower melting temperature, depending on the specific requirements of the job. Building codes currently almost universally require the use of lead-free solder for drinking water piping (and also flux must be approved for drinking water applications), though traditional tin-lead solder is still available. Studies have shown that lead-soldered plumbing pipes can result in elevated levels of lead in drinking water.


title: Soldering

text: Since copper pipe quickly conducts heat away from a joint, great care must be taken to ensure that the joint is properly heated through to obtain a good bond. After the joint is properly cleaned, fluxed and fitted, the torch flame is applied to the thickest part of the joint, typically the fitting with the pipe inside it, with the solder applied at the gap between the tube and the fitting. When all the parts are heated through, the solder will melt and flow into the joint by capillary action. The torch may need to be moved around the joint to ensure all areas are wetted out. However, the installer must take care to not overheat the areas being soldered. If the tube begins to discolor it means that the tube has been over-heated and is beginning to oxidize, stopping the flow of the solder and causing the soldered joint not to seal properly. Before oxidation the molten solder will follow the heat of the torch around the joint. When the joint is properly wetted out, the solder and then the heat are removed, and while the joint is still very hot, it is usually wiped with a dry rag. This removes excess solder as well as flux residue before it cools down and hardens. With a solder ring joint, the joint is heated until a ring of molten solder is visible around the edge of the fitting and allowed to cool.


title: Soldering

text: Of the three methods of connecting copper tubing, solder connections require the most skill, but soldering copper is a very reliable process, provided some basic conditions are met:


title: Soldering

text: Copper is only one material that is joined in this manner. Brass fittings are often used for valves or as a connection fitting between copper and other metals. Brass piping is soldered in this manner in the making of brass instruments and some woodwind (saxophone and flute) musical instruments


title: Soldering

text: Wire brush, wire wool and emery cloth are commonly used to prepare plumbing joints for connection. Bristle brushes are usually used to apply plumbing paste flux. A heavy rag is usually used to remove flux from a plumbing joint before it cools and hardens. A fiberglass brush can also be used.


title: Soldering

text: When soldering pipes closely connected to valves such as in refrigeration systems it may be necessary to protect the valve from heat that could damage rubber or plastic components within, in this case a wet cloth wrapped around the valve can often sink sufficient heat through the boiling of the water to protect the valve.


title: Soldering

text: In the joining of copper tube, failure to properly heat and fill a joint may lead to a 'void' being formed. This is usually a result of improper placement of the flame. If the heat of the flame is not directed at the back of the fitting cup, and the solder wire applied degrees opposite the flame, then solder will quickly fill the opening of the fitting, trapping some flux inside the joint. This bubble of trapped flux is the void; an area inside a soldered joint where solder is unable to completely fill the fittings' cup, because flux has become sealed inside the joint, preventing solder from occupying that space.


title: Soldering

text: Historically, stained glass soldering tips were copper, heated by being placed in a charcoal-burning brazier. Multiple tips were used; when one tip cooled down from use, it was placed back in the brazier of charcoal and the next tip was used.


title: Soldering

text: More recently, electrically heated soldering irons are used. These are heated by a coil or ceramic heating element inside the tip of the iron. Different power ratings are available, and temperature can be controlled electronically. These characteristics allow longer beads to be run without interrupting the work to change tips. Soldering irons designed for electronic use are often effective though they are sometimes underpowered for the heavy copper and lead came used in stained glass work.


title: Soldering

text: Tiffany-type stained glass is made by gluing copper foil around the edges of the pieces of glass and then soldering them together. This method makes it possible to create three-dimensional stained glass pieces.


title: Soldering

text: For attachment of electronic components to a PCB, proper selection and use of flux helps prevent oxidation during soldering; it is essential for good wetting and heat transfer. The soldering iron tip must be clean and pre-tinned with solder to ensure rapid heat transfer.


title: Soldering

text: Electronic joints are usually made between surfaces that have been tinned and rarely require mechanical cleaning, though tarnished component leads and copper traces with a dark layer of oxide passivation (due to aging), as on a new prototyping board that has been on the shelf for about a year or more, may need to be mechanically cleaned.


title: Soldering

text: To simplify soldering, beginners are usually advised to apply the soldering iron and the solder separately to the joint, rather than the solder being applied directly to the iron. When sufficient solder is applied, the solder wire is removed. When the surfaces are adequately heated, the solder will flow around the workpieces. The iron is then removed from the joint.


title: Soldering

text: If all metal surfaces have not been properly cleaned ("fluxed") or brought entirely above the melting temperature of the solder used, the result will be an unreliable ("cold solder") joint, even though its appearance may suggest otherwise.


title: Soldering

text: Excess solder, unconsumed flux and residue is sometimes wiped from the soldering iron tip between joints. The tip of the bit (commonly iron plated to reduce erosion) is kept wetted with solder ("tinned") when hot to assist soldering, and to minimize oxidation and corrosion of the tip itself.


title: Soldering

text: After inserting a through-hole mounted component, the excess lead is cut off, leaving a length of about the radius of the pad.


title: Soldering

text: Hand-soldering techniques require a great deal of skill for the fine-pitch soldering of surface-mount chip packages. In particular ball grid array (BGA) devices are notoriously difficult, if not impossible, to rework by hand.


title: Soldering

text: Various problems may arise in the soldering process which lead to joints which are nonfunctional either immediately or after a period of use.


title: Soldering

text: The most common defect when hand-soldering results from the parts being joined not exceeding the solder's liquidus temperature, resulting in a "cold solder" joint. This is usually the result of the soldering iron being used to heat the solder directly, rather than the parts themselves. Properly done, the iron heats the parts to be connected, which in turn melt the solder, guaranteeing adequate heat in the joined parts for thorough wetting. If using solder wire with an embedded flux core, heating the solder first may cause the flux to evaporate before it cleans the surfaces being soldered.


title: Soldering

text: A cold-soldered joint may not conduct at all, or may conduct only intermittently. Cold-soldered joints also happen in mass production, and are a common cause of equipment which passes testing, but malfunctions after sometimes years of operation.


title: Soldering

text: A "dry joint" occurs when the cooling solder is moved. Since non-eutectic solder alloys have a small plastic range, the joint must not be moved until the solder has cooled down through both the liquidus and solidus temperatures. Dry joints often occur because the joint moves when the soldering iron is removed from the joint. They are weak mechanically and poor conductors electrically.


title: Soldering

text: For hand soldering, the heat source tool is selected to provide adequate heat for the size of joint to be completed. A 100-watt soldering iron may provide too much heat for printed circuit boards (PCBs), while a 25-watt iron will not provide enough heat for large electrical connectors.


title: Soldering

text: Using a tool with too high a temperature can damage sensitive components, but protracted heating by a tool that is too cool or under powered can also cause heat damage. Excessive heating of a PCB may result in delamination — the copper traces may actually lift off the substrate, particularly on single sided PCBs without through hole plating.


title: Soldering

text: While hand-soldering, a heat sink, such as a crocodile clip, may be used on the leads of heat-sensitive components to reduce heat transfer to the components and avoid damaging them. This is especially applicable to germanium parts.


title: Soldering

text: The heat sink limits the temperature of the component body by absorbing and dissipating heat, by reducing the thermal resistance between the component and the air. Meanwhile, the thermal resistance of the leads maintains the temperature difference between the part of the leads being soldered and the component body. Thus, the leads become hot enough to melt the solder while the component body remains cooler. The heat sink will mean the use of more heat to complete the joint, since heat taken up by the heat sink will not heat the work pieces.


title: Soldering

text: Components which dissipate large amounts of heat during operation are sometimes elevated above the PCB to avoid PCB overheating. Plastic or metal mounting clips or holders may be used with large devices to aid heat dissipation and reduce joint stresses.


title: Soldering

text: When visually inspected, a good solder joint will appear smooth, bright and shiny, with the outline of the soldered wire clearly visible. In general a good-looking soldered joint is a good joint.


title: Soldering

text: A matte gray surface is a good indicator of a joint that was moved during soldering. A dry joint has a characteristically dull or grainy appearance immediately after the joint is made. This appearance is caused by crystallization of the liquid solder. Too little solder will result in a dry and unreliable joint.


title: Soldering

text: Cold solder joints are dull and sometimes cracked or pock-marked. If the joint has lumps or balls of otherwise shiny solder, the metal has not wetted properly. Too much solder (the familiar 'solder blob' to beginners) is not necessarily unsound, but tends to mean poor wetting.


title: Soldering

text: A concave fillet is ideal. The boundary between the solder and the workpiece in a good joint will have a low angle. This indicates good wetting and minimal use of solder, and therefore minimal heating of heat sensitive components. A joint may be good, but if a large amount of unnecessary solder is used, then excess heating was obviously required.


title: Soldering

text: Lead-free solder formulations may cool to a dull surface even if the joint is good. The solder looks shiny while molten, and suddenly hazes over as it solidifies even though it has not been disturbed during cooling.


title: Soldering

text: An improperly selected or applied flux can cause joint failure. Without flux the joint may not be clean, or may be oxidized, resulting in an unsound joint.


title: Soldering

text: For electronic work, flux-core solder wire is generally used, but additional flux may be used from a flux pen or dispensed from a small bottle with a syringe-like needle.


title: Soldering

text: Some fluxes are designed to be stable and inactive when cool and do not need to be cleaned off, though they can if desired. If such fluxes are used, cleaning may merely be a matter of aesthetics or to make visual inspection of joints easier in specialised 'mission critical' applications such as medical devices, military and aerospace. For satellites, this will also reduce weight, slightly but usefully. In high humidity, since even non-corrosive flux might remain slightly active, the flux may be removed to reduce corrosion over time.


title: Soldering

text: Some fluxes are corrosive and flux residue must be removed after soldering. If not properly cleaned, the flux may corrode the joint or the PCB. Water, alcohol, acetone, or other solvents compatible with the flux and the parts involved are commonly used with cotton swabs or bristle brushes.


title: Soldering

text: In some applications, the PCB might also be coated in some form of protective material such as a lacquer to protect it and exposed solder joints from the environment.


title: Soldering

text: Used solder contains some of the dissolved base metals and is unsuitable for reuse in making new joints. Once the solder's capacity for the base metal has been reached, it will no longer properly bond with the base metal, usually resulting in a brittle cold solder joint with a crystalline appearance.


title: Soldering

text: It is good practice to remove solder from a joint prior to resoldering — desoldering braids (or wicks) or vacuum desoldering equipment (solder suckers) can be used. Desoldering wicks contain plenty of flux which will remove the oxidation from the copper trace and any device leads that are present. This will leave a bright, shiny, clean junction to be resoldered.


title: Soldering

text: The lower melting point of solder means it can be melted away from the base metal, leaving it mostly intact, though the outer layer will be "tinned" with solder. Flux will remain which can easily be removed by abrasive or chemical processes. This tinned layer will allow solder to flow onto a new joint, resulting in a new joint, as well as making the new solder flow very quickly and easily.


title: Soldering

text: Currently, mass-production printed circuit boards (PCBs) are mostly wave soldered or reflow soldered, though hand soldering of production electronics is also still widely used.


title: Soldering

text: In wave soldering, components are prepped (trimmed or modified) and installed on the PCB. Sometimes, to prevent movement they are temporarily kept in place with small dabs of adhesive or secured with a fixture, then the assembly is passed over flowing solder in a bulk container. This solder flow is forced to produce a standing wave so the whole PCB is not submerged in solder, but rather just touched. The result is that solder stays on pins and pads, but not on the PCB itself.


title: Soldering

text: Reflow soldering is a process in which a solder paste (a mixture of prealloyed solder powder and a flux-vehicle that has a peanut butter-like consistency) is used to stick the components to their attachment pads, after which the assembly is heated by an infrared lamp, a hot air pencil, or, more commonly, by passing it through a carefully controlled oven.


title: Soldering

text: Since different components can be best assembled by different techniques, it is common to use two or more processes for a given PCB. For example, surface mounted parts may be reflow soldered first, with a wave soldering process for the through-hole mounted components coming next, and bulkier parts hand-soldered last.


title: Soldering

text: "Hot-bar reflow" is a selective soldering process where two pre-fluxed, solder coated parts are heated with a heating element (called a thermode) to a temperature sufficient to melt the solder.


title: Soldering

text: Pressure is applied through the entire process (usually 15 seconds) to ensure that components stay in place during cooling. The heating element is heated and cooled for each connection. Up to 4000 W can be used in the heating element, allowing fast soldering, good results with connections requiring high energy.


title: Soldering

text: Environmental legislation in many countries has led to a change in formulation of both solders and fluxes.


title: Soldering

text: The RoHS directives in the European Community required many new electronic circuit boards to be lead-free by 1 July 2006, mostly in the consumer goods industry, but in some others as well. In Japan, lead was phased out prior to legislation by manufacturers, due to the additional expense in recycling products containing lead.


title: Soldering

text: Water-soluble non-rosin-based fluxes have been increasingly used since the 1980s so that soldered boards can be cleaned with water or water-based cleaners. This eliminates hazardous solvents from the production environment, and from factory effluents.


title: Soldering

text: Even without the presence of lead, soldering can release fumes that are harmful and/or toxic to humans. It is highly recommended to use a device that can remove the fumes from the work area either by ventilating outside or filtering the air.


title: Soldering

text: Lead free soldering requires higher soldering temperatures than lead/tin soldering. SnPb 63/37 eutectic solder melts at . SAC lead-free solder melts at .


title: Soldering

text: Nevertheless, many new technical challenges have arisen with this endeavor. To reduce the melting point of tin-based solder alloys, various new alloys have had to be researched, with additives of copper, silver, bismuth as typical minor additives to reduce the melting point and control other properties. Additionally, tin is a more corrosive metal, and can eventually lead to the failure of solder baths.


title: Soldering

text: Lead-free construction has also extended to components, pins, and connectors. Most of these pins used copper frames, and either lead, tin, gold or other finishes. Tin finishes are the most popular of lead-free finishes. Nevertheless, this brings up the issue of how to deal with tin whiskers. The current movement brings the electronics industry back to the problems solved in the 1960s by adding lead. JEDEC has created a classification system to help lead-free electronic manufacturers decide what provisions to take against whiskers, depending upon their application.


title: Cisplatin

text: Cisplatin is a chemotherapy medication used to treat a number of cancers. These include testicular cancer, ovarian cancer, cervical cancer, breast cancer, bladder cancer, head and neck cancer, esophageal cancer, lung cancer, mesothelioma, brain tumors and neuroblastoma. It is given by injection into a vein.


title: Cisplatin

text: Common side effects include bone marrow suppression, hearing problems, including total irreversible hearing loss, usually restricted to one ear, kidney damage, and vomiting. Other serious side effects include numbness, trouble walking, allergic reactions, electrolyte problems, and heart disease. Use during pregnancy can cause harm to the developing fetus. Cisplatin is in the platinum-based antineoplastic family of medications. It works in part by binding to DNA and inhibiting its replication.


title: Cisplatin

text: Cisplatin was discovered in 1845 and licensed for medical use in 1978 and 1979. It is on the World Health Organization's List of Essential Medicines.


title: Cisplatin

text: Cisplatin is administered intravenously as short-term infusion in normal saline for treatment of solid and haematological malignancies. It is used to treat various types of cancers, including sarcomas, some carcinomas (e.g., small cell lung cancer, squamous cell carcinoma of the head and neck and ovarian cancer), lymphomas, bladder cancer, cervical cancer, and germ cell tumors.


title: Cisplatin

text: Cisplatin is particularly effective against testicular cancer; its adoption has increased the cure rate from 10% to 85%.


title: Cisplatin

text: A paper published on 17 August 2022 demonstrated that a nanoengineered topical transmucosal cisplatin delivery system can be used as a treatment of oral cancer. PRV111, a nanotechnology-based system for local delivery of cisplatin loaded chitosan particles gives rise to anti-tumor responses in squamous cell tumor. It also reduces cisplatin associated toxicities and prevented tumor recurrence in vivo"." A high concentration of cytotoxic drugs in the tumor and regional lymph nodes is also retained by PRV111 shown in human studies. Such findings indicate that PRV111 may become a possible treatment of oral cancer in the future.


title: Cisplatin

text: Although further trials are necessary, cisplatin has been studied with Auger therapy to increase the therapeutic effects of cisplatin, without increasing normal tissue toxicities.


title: Cisplatin

text: Cisplatin can increase levels of sphingosine-1-phosphate in the central nervous system, contributing to the development of chemotherapy-related cognitive impairment.


title: Cisplatin

text: Cisplatin interferes with DNA replication, which kills the fastest proliferating cells, which in theory are cancerous. Following administration, one chloride ion is slowly displaced by water to give the aquo complex "cis"-[PtCl(NH)(HO)], in a process termed aquation. Dissociation of the chloride is favored inside the cell because the intracellular chloride concentration is only 3–20% of the approximately 100 mM chloride concentration in the extracellular fluid.


title: Cisplatin

text: The water molecule in "cis"-[PtCl(NH)(HO)] is itself easily displaced by the "N"-heterocyclic bases on DNA. Guanine preferentially binds. Subsequent to formation of [PtCl(guanine-DNA)(NH)], crosslinking can occur via displacement of the other chloride, typically by another guanine. Cisplatin crosslinks DNA in several different ways, interfering with cell division by mitosis. The damaged DNA elicits DNA repair mechanisms, which in turn activate apoptosis when repair proves impossible. In 2008, researchers were able to show that the apoptosis induced by cisplatin on human colon cancer cells depends on the mitochondrial serine-protease Omi/Htra2. Since this was only demonstrated for colon carcinoma cells, it remains an open question whether the Omi/Htra2 protein participates in the cisplatin-induced apoptosis in carcinomas from other tissues.


title: Cisplatin

text: Most notable among the changes in DNA are the 1,2-intrastrand cross-links with purine bases. These include 1,2-intrastrand d(GpG) adducts, which form nearly 90% of the adducts, and the less common 1,2-intrastrand d(ApG) adducts. 1,3-intrastrand d(GpXpG) adducts occur but are readily excised by the nucleotide excision repair (NER). Other adducts include inter-strand crosslinks and nonfunctional adducts that have been postulated to contribute to cisplatin's activity. Interaction with cellular proteins, particularly HMG domain proteins, has also been advanced as a mechanism of interfering with mitosis, although this is probably not its primary method of action.


title: Cisplatin

text: Cisplatin combination chemotherapy is the cornerstone of treatment of many cancers. Initial platinum responsiveness is high, but the majority of cancer patients will eventually relapse with cisplatin-resistant disease. Many mechanisms of cisplatin resistance have been proposed, including changes in cellular uptake and efflux of the drug, increased detoxification of the drug, inhibition of apoptosis and increased DNA repair. Oxaliplatin is active in highly cisplatin-resistant cancer cells in the laboratory; however, there is little evidence for its activity in the clinical treatment of patients with cisplatin-resistant cancer. The drug paclitaxel may be useful in the treatment of cisplatin-resistant cancer; the mechanism for this activity is as yet unknown.


title: Cisplatin

text: Transplatin, the "trans"-stereoisomer of cisplatin, has formula "trans"-[PtCl(NH)] and does not exhibit a comparably useful pharmacological effect. Two mechanisms have been suggested to explain the reduced anticancer effect of transplatin. Firstly, the "trans" arrangement of the chloro ligands is thought to confer transplatin with greater chemical reactivity, causing transplatin to become deactivated before it reaches the DNA, where cisplatin exerts its pharmacological action. Secondly, the stereo-conformation of transplatin is such that it is unable to form the characteristic 1,2-intrastrand d(GpG) adducts formed by cisplatin in abundance.


title: Cisplatin

text: Cisplatin is the square planar coordination complex cis-[Pt(NH)Cl]. The prefix "cis" indicates the "cis" isomer in which two similar ligands are in adjacent positions. The systematic chemical name of this molecule is "cis"–diamminedichloroplatinum, where "ammine" with two m's indicates an ammonia (NH) ligand, as opposed to an organic amine with one m.


title: Cisplatin

text: The compound "cis"-[Pt(NH)Cl] was first described by Italian chemist Michele Peyrone in 1845, and known for a long time as Peyrone's salt. The structure was deduced by Alfred Werner in 1893. In 1965, Barnett Rosenberg, Van Camp et al. of Michigan State University discovered that electrolysis of platinum electrodes generated a soluble platinum complex which inhibited binary fission in "Escherichia coli" ("E. coli") bacteria. Although bacterial cell growth continued, cell division was arrested, the bacteria growing as filaments up to 300 times their normal length. The octahedral Pt(IV) complex "cis"-[PtCl(NH)], but not the "trans" isomer, was found to be effective at forcing filamentous growth of "E. coli" cells. The square planar Pt(II) complex, "cis"-[PtCl(NH)] turned out to be even more effective at forcing filamentous growth. This finding led to the observation that "cis"-[PtCl(NH)] was indeed highly effective at regressing the mass of sarcomas in rats. Confirmation of this discovery, and extension of testing to other tumour cell lines launched the medicinal applications of cisplatin. Cisplatin was approved for use in testicular and ovarian cancers by the U.S. Food and Drug Administration on 19 December 1978. and in the UK (and in several other European countries) in 1979.


title: Cisplatin

text: In 1983 pediatric oncologist Roger Packer began incorporating cisplatin into adjuvant chemotherapy for the treatment of childhood medulloblastoma. The new protocol that he developed led to a marked increase in disease-free survival rates for patients with medulloblastoma, up to around 85%. The Packer Protocol has since become a standard treatment for medulloblastoma. Likewise, cisplatin has been found to be particularly effective against testicular cancer, where its use improved the cure rate from 10% to 85%.


title: Cisplatin

text: Recently, some researchers have investigated at the preclinical level new forms of cisplatin prodrugs in combination with nanomaterials in order to localize the release of the drug in the target.


title: Cisplatin

text: Syntheses of cisplatin start from potassium tetrachloroplatinate. Several procedures are available. One obstacle is the facile formation of Magnus's green salt (MGS), which has the same empirical formula as cisplatin. The traditional way to avoid MGS involves the conversion of KPtCl to KPtI, as originally described by Dhara. Reaction with ammonia forms PtI(NH) which is isolated as a yellow compound. When silver nitrate in water is added insoluble silver iodide precipitates and [Pt(OH)(NH)](NO) remains in solution. Addition of potassium chloride will form the final product which precipitates In the triiodo intermediate the addition of the second ammonia ligand is governed by the trans effect.


title: Cisplatin

text: A one-pot synthesis of cisplatin from KPtCl has been developed. It relies on the slow release of ammonia from ammonium acetate.


title: Tom Brittney

text: Tom Christopher Brittney (born 26 October 1990) is an English actor who is best known for playing the Reverend Will Davenport in "Grantchester" (2019–present).


title: Tom Brittney

text: Tom Brittney was born in Gravesend, Kent on 26 October 1990. He moved to Devon when he was 12, where his mother taught drama.


title: Tom Brittney

text: Brittney's first TV appearance was in the daytime soap opera "Doctors" in 2013. The following year, he joined the recurring cast of historical/fantasy series "Outlander", in which he played Lieutenant Jeremy Foster, one of Black Jack Randall's men. He also appeared briefly in an episode of the BBC TV series "Call the Midwife", and a short film called "The Unknowns". In 2015, he was cast as DS Ken Howells in the crime drama "The Five", written by U.S. crime author Harlan Coben. He also appeared as a recurring character in the third season of "The Syndicate", playing Tyler Mitchell, and played Roger Lockwood in the TV series "UnReal". In the same year, he played Greg in "Humans". He appeared in "Film Stars Don't Die in Liverpool" as Tim.


title: Tom Brittney

text: In 2017, he appeared as David in "X Company", and played Conrad Habicht in an episode of "Genius". In June 2018, Brittney joined the cast of the ITV crime drama "Grantchester" as the Reverend Will Davenport, the new lead character. Brittney starred as Billy in the drama "Make Me Famous" in 2020. Written by Reggie Yates and directed by Peter King, the film explores the impact and consequences of fast fame on reality TV participants and their close friends and families.


title: Tom Brittney

text: On acting, Brittney revealed that he had always wanted to be an actor: "having that ambition makes it all the more painful when it doesn't come to reality. I didn't have a plan B [...] luckily, I'd like to think it's working out, but it's a tough journey, I think putting all your love and hope into your ambition."


title: Tom Brittney

text: Brittney was diagnosed with body dysmorphia. In 2020, he revealed: "I used to take off days from school, because I just hated the way that I looked [...] I'm very insecure with the way that I look and I'll beat myself up about performances."


title: Alistair Petrie

text: Alistair Petrie (born 30 September 1970) is a British actor. He has starred in "The Bank Job" (2008), "Cloud Atlas" (2012), "Rush" (2013) and "Rogue One: A Star Wars Story" (2016). Petrie has also starred in the Channel 4 television series "Utopia", the BBC One television series' "The Night Manager, Sherlock," and "Undercover" and as Mr. Groff in the Netflix original comedy-drama series "Sex Education".


title: Alistair Petrie

text: Petrie was born 30 September 1970 in Catterick, North Riding of Yorkshire. He was brought up in the Middle East, mainland Europe and East Africa. His father was an RAF fighter pilot.


title: Alistair Petrie

text: Petrie spent his early career in theatre around the country before joining the RSC where productions included Shakespeare's "Troilus and Cressida" and Henrik Ibsen's "Brand" opposite Ralph Fiennes. In 2005, he joined the National Theatre, where he stayed for 28 months performing in "His Dark Materials", Shakespeare's "Henry IV" alongside Sir Michael Gambon and David Edgar's "Playing With Fire". Other theatre work includes The Earl of Wessex in the 2015 West End Production of "Shakespeare in Love". In 2008, Petrie played the lead role of "Man" in "Mine, Shared Experience" at the West Yorkshire Playhouse, Leeds.


title: Alistair Petrie

text: In 1996, Petrie appeared as Robert Martin in "Emma." He featured in the BBC production of "The Forsyte Saga" as George Forsyte in 2002-2003, and he played a brief role in the music video for "Bellissimo" by Ilya directed by the Guard Brothers in 2004. In 2007 he appeared in "Marc Munden's The Mark of Cain", "The Whistleblowers" and "Cranford".


title: Alistair Petrie

text: In 2009 he played Heaton in the film "The Duchess", and in 2010 played Billing in the horror film "Devil's Playground". Petrie appeared as Philip Lisle in "The Bank Job", as Felix Finch in the 2012 film "Cloud Atlas", as Stirling Moss in "Rush," and as General Davits Draven in "Rogue One: A Star Wars Story".


title: Alistair Petrie

text: Also in television, Petrie has portrayed Geoff in Channel 4's "Utopia", Alexander "Sandy" Langbourne in "The Night Manager", and Robert Greenlaw in BBC1's "Undercover". He played the role of Major James Sholto in the second episode of Season 3 of the BBC TV series "Sherlock", which aired on 5 January 2014. In 2018, he played Dr. Stephen Stanley in "The Terror" (based on the novel of the same name), a supernatural horror series about Franklin's lost expedition. In 2019, Petrie began playing Mr. Groff in the Netflix original comedy-drama series "Sex Education".


title: Alistair Petrie

text: Petrie is an Ambassador for Borne, a medical research charity looking to identify the causes of premature birth. In 2007, he and his wife swam the English Channel to fundraise for the charity, becoming the first married couple to complete the crossing.


title: The Good Karma Hospital

text: The Good Karma Hospital is a medical drama series produced by Tiger Aspect Productions for ITV about a disillusioned doctor, Ruby Walker, who travels to South India hoping to make a fresh start. It stars Amanda Redman, Amrita Acharia, James Krishna Floyd, and Neil Morrissey. The series is shot in Unawatuna in southern Sri Lanka, Thiranagama Golden Beach Restaurant and some other places in Galle District.


title: The Good Karma Hospital

text: "The Good Karma Hospital" was recommissioned for a second and a third series. Filming for the second series started in August 2017 and it was broadcast from 18 March 2018. Series 3 first aired in October 2019 in Australia, with a UK premiere in March 2020. A fourth series started airing in the UK on 23 January 2022. In November 2022 it was announced that the show has been cancelled after its fourth series.


title: The Good Karma Hospital

text: A medical drama about a junior doctor, Ruby Walker, who becomes disillusioned with her life and broken relationship, and decides to leave the UK. Seeing an advertisement for a hospital job in south India, she travels there hoping to make a fresh start and finds herself working at The Good Karma Hospital, an under-resourced and overworked cottage hospital run by an eccentric English expat, Dr. Lydia Fonseca.


title: The Good Karma Hospital

text: Gayle Pennington of the "St. Louis Post Dispatch" described the first season as “a magical combination of familiar and exotically foreign…. a drama you’ll remember long after you finish watching it.“


title: The Good Karma Hospital

text: Writing for the Indian digital news publication Scroll, Vikram Johri says: ”The series…has its heart in the right place even if it cannot entirely avoid tone-deaf generalisations… Ignore these irritants and the show can be engaging, especially when it is not trying to train the viewer in Indian mores… It is Walker who is the show’s beating heart. Unaware of Indian customs and rituals..she takes to her new home and assignment with gusto, quickly imbibing that all-important Indian lesson of making do with what’s available. As a paediatrician, she finds herself performing minor surgical procedures. However, it is her deep reserves of empathy – and the gentle eyes of the actress who plays her – that make her the ideal doctor. “


title: The Good Karma Hospital

text: Deborah Ross for Event Magazine says that the series, “…does not have an original bone in its body…. It’s intended as Sunday night ‘unchallenging’ fare but if you can sit through it without feeling so challenged you want to throw a shoe at the TV, you are made of stronger stuff than I. “


title: David Tua

text: Faumuina To'aletai Mafaufau David Tua (born 21 November 1972), best known as David Tua, is a Samoan-New Zealand former professional boxer who competed from 1992 to 2013. A highly ranked heavyweight contender for most of his career, Tua was known for his formidable punching power, especially in his devastating left hook. He scored sixteen wins by knockout in the first round, which included knockouts of world heavyweight champions John Ruiz and Michael Moorer within thirty seconds of the first round, as well as late stoppages of world champions Oleg Maskaev and Hasim Rahman. He was ranked by BoxRec in the world's top 10 heavyweights from 1996 to 2003, reaching his highest ranking of No.3 in 1998. Tua ended his career with a knockout-to-win ratio of 82.6%. In a 2003 article by "The Ring" magazine, Tua was ranked 48th on a list of 100 greatest punchers of all time.


title: David Tua

text: Nicknamed the "Tuamanator", his fast-paced bob and weave pressure fighting style has often drawn comparisons to Mike Tyson. Tua fought many of the best boxers of his era and challenged once for the unified world heavyweight title against Lennox Lewis in 2000. In his five professional losses, Tua was never subject to a stoppage, and possessed one of the most durable chins of his time.


title: David Tua

text: Tua said that he lived with four brothers, four sisters and ten other relatives while growing up. Tua said that his mother worked three jobs, and Tua said that his father worked long hours. Tua said that his father forced him to start boxing when he was seven years old, and Tua said that he is grateful to his father for introducing him to boxing.


title: David Tua

text: In his early career, Tua trained three days a week at a small gym in Mangere Bridge, under boxing trainer Gerry Preston. Tua became New Zealand national heavyweight champion in 1988 at age 15.


title: David Tua

text: At the age of 19 Tua won a bronze medal at the 1992 Summer Olympics in Barcelona. He lost his semi-final to David Izonritei, whom he would later knock out as a professional. Tua turned professional later the same year.


title: David Tua

text: In Tua's 1997 fight against Ike Ibeabuchi, the two fighters combined to set the record for most punches thrown in a heavyweight fight on record. Ibeabuchi won the decision, handing Tua his first professional loss. Prior to this, Tua had scored devastating knockouts against future titlist John Ruiz (via 1st-round KO, in only 19 seconds) and Darroll Wilson. Tua also beat David Izon and future champion Oleg Maskaev to set up the fight with Ibeabuchi. After the loss to Ibeabuchi, Tua took on future champ Hasim Rahman and TKO'd Rahman in the 10th round. The victory over Rahman marked the beginning of Tua's struggles with his weight. He ballooned up to 253 pounds when he defeated Obed Sullivan in 2000 by KO. Later that year, he weighed 245 pounds in the loss to Lennox Lewis. Tua was disappointing in the fight, with both fighters avoiding each other and Tua not throwing combinations. Tua lost a clear-cut decision.


title: David Tua

text: The fight with Lewis was for the WBC, IBF, & IBO heavyweight titles and took place in November 2000. Tua lost on points by a wide margin.


title: David Tua

text: Following the Lewis loss, Tua regained steam with a KO over Danell Nicholson but lost by a close decision in his next fight to future champion Chris Byrd. In 2002 he beat prospect Fres Oquendo and demolished Michael Moorer in his next fight with a powerful shot 30 seconds into the first round, which put Moorer out cold. In 2003 he drew in a 12-round rematch with Rahman.


title: David Tua

text: Tua was inactive for over two years before he stepped into the ring on 31 March 2005 and bested Talmadge Griffis in a 10-round bout—ending the match and earning a TKO victory with 26 seconds remaining. Tua's next contest in October 2005 ended in a split decision over Cisse Salif with Tua dominating in the late rounds.


title: David Tua

text: Tua defeated Edward Gutierrez by knockout in the fourth round of a scheduled 10-rounder on 26 July 2006. The fight was held at the Manhattan Center ballroom in New York City, and featured on ESPN2. Tua started slowly, scored a knockdown with his famous left hook in the second round, and put Gutierrez down for the count in the fourth round with a combination of two left hooks, one to the head and the decisive one to the body.


title: David Tua

text: In November 2006 Tua defeated Maurice Wheeler in the seventh round of a scheduled 10-rounder by knockout. Tua ended the bout with a solid left uppercut to the body which immediately sent the howling Wheeler to the canvas.


title: David Tua

text: Tua continued his comeback in February 2007 with a unanimous decision over Robert Hawkins in a 10-round bout. Tua ended the match being the aggressor and hurt Hawkins in both the ninth and tenth rounds with body punches, but was unable to end the match with a knockout.


title: David Tua

text: Tua, looking in good shape and weighing in at 237½ lbs (his lightest fight weight since 2001), was featured as the main event of a Pay Per View show on 18 August 2007 in Sandy, Utah and ended the bout quickly with a first-round knockout of Mexican champion Saul Montana. Tua threw two powerful left hooks to the head that sent Montana sprawling to the canvas giving Tua his sixth win in a row.


title: David Tua

text: Tua, again looking in good shape and weighing in at 234 lbs, fought the unheralded Cerrone Fox at the Soaring Eagle Casino, Mt. Pleasant, Michigan on 7 September 2007. Tua made short work of his over matched opponent ending the bout at 1:41 of the second round.


title: David Tua

text: While Tua's promoter, Cedric Kushner, stated Tua was scheduled to fight an opponent on 18 October 2007, the fight never materialized.


title: David Tua

text: Tua fought fellow New Zealander Shane Cameron at Mystery Creek, Hamilton on 3 October 2009 with Tua knocking Cameron out seven seconds into the second round to pick up the WBO Asia Pacific and Oriental Heavyweight titles. The promoters for the fight were John McRae and David Higgins of Duco Events. The fight had been scheduled for an earlier date, but was delayed due to Cameron having surgery on a fractured hand.


title: David Tua

text: On 31 March 2010 Tua fought Friday Ahunanya, winning on points after 12 rounds. The fight promoters for this fight were again John McRae and David Higgins of Duco Events.


title: David Tua

text: The Tua-Barrett fight had been tentatively scheduled for 26 June in São Paulo, Brazil. However, the fight was moved to 17 July at the Tropicana Casino and Resort in Atlantic City in a bid to promote David Tua's career in the United States. At 38 years old, Monte Barrett (34-9, 20 KOs) was viewed by some as an easy opponent for Tua as he had lost his previous three fights. The match was a controversial draw with Tua being knocked down for the first time in his professional career late in the 12th round.


title: David Tua

text: Tua fought Demetrice King on 19 March 2011. Tua defeated King by unanimous decision with the scores of 100–91, 100–91, and 100–90.


title: David Tua

text: Tua's rematch against Monte Barrett on 13 August 2011 resulted in a unanimous points decision going in favour of Barrett. The judges scored the bout 113–112, 115–112, and 115–112.


title: David Tua

text: In December 2011, it emerged that Monte Barrett tested positive for banned stimulant methylhexanamine following a urine test after his 13 August points decision over Tua. Tua's lawyer, Blair Edwards, called for action against the 40-year-old New Yorker requesting the return of Tua's WBO Asia-Pacific and Oriental titles and the restoration of ranking points.


title: David Tua

text: In June 2013 it was confirmed that Tua was once again getting back into the ring. Belarusian Alexander Ustinov defeated him by unanimous points decision, following which he announced his retirement from professional boxing. "Ringside Report" were mixed in their evaluation of his career, referring to him as "one of the best heavyweights never to win a world title".


title: David Tua

text: On 10 October 1992 Tua appeared on the New Zealand version of the gameshow "Wheel of Fortune". He had asked for an "O for Olsen" (possibly a reference to Olsen Filipaina) but this was heard by some (and widely reported) as "O for awesome". He requested "P" when buying a vowel on the same episode. He was also heard to ask if he could buy a "constonant" during the same show.


title: David Tua

text: From 1992 to 2003, Tua was managed by former boxer Kevin Barry, who also trained him from 2001. But in 2003, Tua ended his business relationship with Barry and financial manager Martin Pugh. Though Barry accepted his dismissal as trainer, he resisted Tua's decision to end their contract, which still had two years to go.