Pearls of wisdom from Louis Rossmann - worth thinking about - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: February 18, 2016, 06:49:16 pm
content: Introducing a collection of Wisdom from Louis Rossmann - APPLE Laptop repair specialist.PART 1 of 3I recently discovered the You Tube video channel of Louis Rossmann after seeing a post on here regarding reflowing GPU's.After viewing his video stating that re-flowing and re-balling GPU's is bulls**t and not a repair, I decided to watch more of his offerings. Do not be put off by some of his videos that contain colourful language or rants...... he has a lot of good and interesting content along with some pearls of wisdom for people in the independent repair industry.Louis is a self-made business man and can come across as a bit brash in some videos, this is just who he is and viewers would be wise to stick with watching as this gentleman is actually a really honourable and nice guy. The more of his videos that you watch, the more you realise this. Louis produced the collection of videos as a service to those wishing to also learn motherboard repair. He has invested quite a lot of money in his audio visual kit that makes these videos possible. Kudos to him and also my thanks for his efforts to educate others.I know that this is Dave's forum but I hope he will not mind me sharing some of the pearls of wisdom that I have taken away from Louis's videos.Louis Rossmann Pearls is Wisdom for repair businesses1. You can never have too much good FLUX (well almost never anyway)2. Treat your friends repairs no different to your commercial repairs and keep your friendship3. "You touched it, you own it" Responsibility for customers equipment.4. Solution based charging as opposed to component based charging.5. Discount ...... Why?6. Outsourcing component level repair work .... Potential pitfalls and customer satisfaction.7. To diagnose through multiple testing or just replace the likely component? Knowledge is power.8. Salvaging components from donor PCB's when is it acceptable ?9. Sourcing unobtainium chips and the pitfalls of such.10. Re-flowing and re-balling GPU's, is it truly a repair ?11. Finding a short circuit to 0V on a PCB without a $1000 Thermal Camera. Only 5 Cents of IPA12. Buy decent FLUX from a reputable source, not Vaseline from China !13. Is an $1800 JBC hot air station essential for good results ? No, it just makes life easier and the job quicker.14. Using an Ultrasonic bath. The correct type and cleaning fluid is important.15. The economics of repairs. iPhone Vs Laptop.16. Customer attitude towards 3rd party repair...... Warranty claims.17. You cannot please all the people, all of the time.18. Accepting bare motherboards for repair ..... Not a good idea19. Accepting boards from other repair centres ..... Well messed with ! Customer Vs Contract work ?20. You can never have too much good flux !

author: Fraser
author_rank: Super Contributor
timestamp: February 18, 2016, 06:51:22 pm
content: Part 2 of 3The long version1. You can never have too much good FLUX (well almost never anyway)As Louis proves in his videos, the regular application of a good quality flux when working on SMT is essential to quality solder joints. There may be those who think that he uses too much flux but he stands by his results. Louis works on tiny SMT devices so his videos appear to show masses of flux in play but the truth is less shocking. It just shows how small the components are that he works on ! He recommends AMTECH tacky flux but people will have their own favourites I am sure. I do like the performance of his flux though.2. Treat your friends repairs no different to your commercial repairs and keep your friendshipAn interesting one this. I, and I am sure others are guilty of doing 'favours' for friends. Louis points out that if you treat your friends differently to your customers when it comes to repair you may be doing them a disservice. He points out that a customer paying full rates expects a fast repair. A friend getting such at a discount, or free, may be less demanding. This can result in you taking longer to do a repair and so try the patience of your friend. Hmmmm food for thought. Louis does admit that he sometimes applies a discount though.3. "You touched it, you own it" Responsibility for customers equipmentLouis points out that there is a common view that once you touch something for repair "you own it" in terms of responsibility for it. this was an interesting concept for me as it means that once you accept a device or PCB in for repair, you are responsible for it but also you have responsibility for all faults, both now, and in the future ! You may only replace a fuse or fit a new resistor, but the customer can take the view that whatever YOU did, caused the GPU to fail 2 months later ! This sort of customer expects a warranty repair on a completely unrelated fault. A hazard of the profession ?4. Solution based charging as opposed to component based chargingLouis operates a solution based charging system where a customer is quoted a fixed price of $300 to $400 (depending upon model ?) to repair a motherboard. The fault could be a 10 Cent resistor or capacitor, but the charge remains the same. Louis explains this well in his video. When you repair a customers motherboard, you have to diagnose the cause of the fault. This takes knowledge and experience. Such is not free. In addition to this, you are taking responsibility for someone’s very valuable hardware and any harm that may come to it. Finally, as noted above, some customers take the view that any faults that follow a repair must be due to something the repair technician did and so they claim a warranty repair at no cost. The pricing structure for repairs needs to reflect these factors in order to make a reasonable profit at the end of the year. It must also be understood that for every easy/quick repair, there can a really nasty one that takes much time and effort to resolve. One offsets the other in financial terms.5. Discount ...... Why?Some customers do not like the fixed price charging that Louis operates and accuse him of a rip-off. As he states these customers are welcome to go elsewhere for their repair. Some ask for discount and are often disappointed with Louis's response of "No". See the pricing model above. What reason has Louis to discount because someone wants to be a cheapskate? Remember that his customer base is usually wealthy people in New York. They know how expensive Louis's shop lease must be yet they want discount for his excellent repair services. The wealthy stay wealthy by being tight ? Louis does admit to giving a discount is specific deserving situations so he does not have a heart of stone.6. Outsourcing component level repair work .... Potential pitfalls and customer satisfactionLouis used to send his motherboards out for repair by an unnamed 3rd party. This was before he had studied motherboard repair for himself. He details some of the appalling work practices and poor trade-craft exhibited by this outside company and the effect that it had on his reputation with customers. When he sent out a Motherboard for repair, the customer had to wait a week for its return. Louis would then find that the repair did not work, or there was another fault present. The customer would be told that it would be another weeks before they had their computer back. Guess who the customer blames....not the third party repair centre, no, they blamed Louis. This is what led Louis to attend night school and learn the skills needed for motherboard repair. He can normally repair a motherboard in less than 20 minutes. Significantly faster than sending it to a third party who may, or may not make a good job of the repair. I suppose the moral of this is, do not entrust your reputation to people who have little or no interest in upholding it for you. Keep your repairs in-house whenever possible as that provides quality control.7. To diagnose through multiple testing or just replace the likely component? Knowledge is power.It will not come as a surprise to the readership, but in business, time is money. Louis's business is no different. He aims to repair a Motherboard in less than 20 minutes and has plenty of boards awaiting his attention. This is very different to the hobbyist who takes his or her time over a repair as this is a learning process and part of the enjoyment to many. In business, however, the repair technician just wants the fault repaired as fast as is practical. For this reason Louis does not always carry out a myriad of tests and measurements on a Motherboard. His in depth knowledge of the boards, visual inspection and some quick measurements normally lead him to the source of the problem. As Louis specialises in fluid damaged APPLE laptops, he has gained great knowledge of their circuits and the signs of fluid damage on components. He will sometimes remove all suspect components and replace them without actually proving which individual component was faulty by tests. This may seem extreme, but it is fast and also reduces the chances of a future problem with fluid contaminated components continuing to degrade over time. Component costs can be very low so this still makes economic sense. Where rare or expensive components are involved, Louis spends more time proving that the part actually is in need of replacement. It is an interesting contrast between business repair and hobbyist repair techniques.9. Sourcing unobtainium chips and the pitfalls of suchSome chips in the computers that Louis repairs are either obsolete or were never made available to buy. APPLE appears to use some chips that are only available when bought in the 1000's of units or even then, only available to APPLE under agreements with the fabricator. Such chip non-availability is a challenge for a third party offering component level repair. APPLE has no interest in repairing to component level or helping others who do. The solution may appear ugly to some. Louis buys scrap APPLE motherboards for between $20 and $30 apiece. Some come from repair centres where the board was considered beyond repair. Louis buys these in bulk and uses them as part donors to repair customers computers. Oh No .... not used partsyou may say but the alternative is for the customer to buy a new computer at significant cost. Whether you tell the customer that used parts have been used in the repair is open to debate. Some parts used in the APPLE laptops are prone to failure so those on the donor boards can also be faulty. A bit of a nightmare when working with BGA chips and all that they entail. GPU BGA chips are especially prone to failure and it is a brave tech who trusts a used one removed from an anonymous motherboard. Remember, reputation is everything and a business does not want 'bounce backs'. A used component may fail soon after being reused due to the stresses involved in the removal and re-fitting process. This is a risk that must be considered, but Louis has field experience which tells him which chips he can recover and those that come with the risk of later failure. Another source of such unavailable chips is China and ebay. Louis does warn that it is like playing RUSSIAN ROULETTE when following that path as the chips can be bad. Not amusing when you have just installed a huge BGA. Fake chips are also a risk. He buys from his trusted sources having had good experience with them over the years. Some sources he mentions as unwise are very risky indeed.10. Reflowing and re-balling GPU's, is it truly a repair ?Louis did a very interesting video discussing why re-flowing or re-balling a GPU is not a true repair. He considers it nothing more than a temporary, unpredictable Band-Aid on the problem. Louis identifies the problem as not the BGA solder balls, but rather, the ‘bump’ contacts between the flip chip and the substrate to which it is adhered. Heating the GPU caused expansion and contraction within its structure. Heating to high temperatures can cause an intermittent contact in the flip chip bump array to be temporarily resolved. The problem will however still be present and return at some unpredictable point in the future. The customers who come to Louis are often heavy users of the GPU so he will not risk their work or reputation by reflowing or re-balling an intermittent GPU. Replacement with a new GPU is the only true repair.

author: Fraser
author_rank: Super Contributor
timestamp: February 18, 2016, 06:53:11 pm
content: Part 3 of 311. Finding a short circuit to 0V on a PCB without a $1000 Thermal Camera. Only 5 Cents of IPAIn several videos, Louis demonstrates how he finds a short circuit to 0V using basic tools and techniques. Amongst his techniques are checking voltage, continuity to 0V and detecting the heating effect of current running through the faulty component. Louis uses his top lip as a thermal sensor ! He also applied IPA to a suspect area of the motherboard and watches where it evaporates most quickly. His method works well and costs only 5 Cents in IPA ! I personally use one of my thermal cameras, but I have no issue with the method that Louis applies in his repairs. Watch his videos on finding short circuits to see more of his techniques, including applying an external supply capable of high current.12. Buy decent FLUX from a reputable source, not Vaseline from China !Louis used to use a Kester FLUX but now prefers AMTECH tacky flux. He extols the virtues of the AMTECH product but warns that it is more expensive and so many fakes are sold. The fakes usually come from China and AMTECH flux is made in the USA ! The Ex China pricing is too good to be true and buyers can end up with little more than a syringe of cheap Vaseline petroleum jelly. AMTECH have a poor distribution process and this makes it hard for some to purchase. Louis reveals that AMTECH will supply direct to the customer but some archaic processes are involved, including sending a FAX !The importance of good quality flux is well known and Louis is just highlighting the risks of buying such on eBay as much Branded product from China may well be fake. His recommendation is to buy from a reputable source only.13. Is an $1800 JBC hot air station essential for good results ? No, it just makes life easier.Louis was using a $600 genuine HAKKO Hot Air station for his motherboard repairs. It served him well but he decided to test Weller and JBC hot air station offerings. His review videos provide comment on both stations and both are worthy of use in any PCB repair workshop, and perform well. In one video, Louis asks himself whether the $1800 JBC is really worth the extra money over the Weller or HAKKO stations. He states that the JBC is a joy to use and heats up far quicker than the old HAKKO. The ease and speed with which it enables him to remove chips impresses him, but he would not spend $1800 on a hot air station. His JBC was bought for him as a gift. Louis stated that the $600 HAKKO worked and got the job done, it was just a bit slower than the JBC though.14. Using an Ultrasonic bath. The correct type and cleaning fluid is importantLouis specialises in repairing motherboards that have been contaminated with fluid. The fluids can be from all manner of sources, including cat urine ! The fluid gets onto the motherboard and even creeps under the BGA chips where it is very hard to remove properly. Soaking the PCB in IPA is an old trick in industry but such is not good enough for the sorts of boards that Louis has to deal with. He uses an Ultrasonic cleaning bath. Yep, you read right, an Ultrasonic cleaning bath. I can hear cries of horror already !. Louis uses an Ultrasonic Cleaning bath that is designed for electronics and it has a swept oscillator instead of the usual fixed 40-42KHz oscillation. In one of his videos, Louis details how such an ultrasonic bath should be used and the cleaning fluid that should be added to the water. He recommends the proper fluid for the task and not dish washer soap or Windex !. He also states that use of inappropriate ultrasonic baths and cleaning fluids can ruin an otherwise repairable motherboard. He has shown the results of inappropriate ultrasonic cleaning in some of his videos.The bad news is that the correct swept frequency ultrasonic bath costs almost $1000. A lot for a hobbyist but the unit pays for itself when used as part of a business.15. The economics of repairs. iPhone Vs LaptopThere are many third party repair companies offering repair of iPhones, iPads and APPLE Laptops. Louis states why he does not do repairs to iPhones and iPads, except for data recovery purposes.As he states, the repair of an iPhone or iPad can take just as long as that of a Laptop motherboard….yet he will likely only be able to charge $200 for such a repair. That is to say, he would be repairing a board for which he will charge almost half his normal price applied to a laptop motherboard and it will have taken him just as long to complete. I can see his logic here. He also states that owners of iPhones and iPads are often lost without them and want literally instant repair. He recounts a story of a woman who literally could not bear to be parted from her iPhone despite the fact it was not working ! Nightmare customers and only half the financial return of a laptop repair….no thanks says Louis. Good call.16. Customer attitude towards 3rd party repair...... Warranty claimsThis was covered earlier but is worthy of a repeat. It is not unusual for a customer to consider that the warranty a repair centre provides on a specific repair applies to ANY future failure falling within the repair warranty period. That is to say, when Louis repairs a motherboard that had a charging circuit failure, he may well have the customer back in his premises demanding warranty repair for a failed LCD backlight ! This is a hazard of the profession as customers can be pretty daft when it comes to understanding that the original repair has no connection to the new fault. Of course where a fluid damaged PCB is involved, I would be concerned that hidden corrosion in Via’s etc. could cause problems in the future. No easy answer to this situation. You just have to suck it up I suppose. This is one of the reasons why a repair charge has to include a decent profit element to cover bounce- backs.17. You cannot please all the people, all of the timeThis one is pretty self-exoplanetary. Louis understands that you cannot please all of the people, all of the time. Trying to do so can end in tears and a burn-out. Good advice as I was guilty of trying to please everyone, all of the time and it was a total nightmare ! Manage people’s expectations.18. Accepting bare motherboards for repair ..... Not a good ideaLouis used to offer a ‘motherboard only’ service where the owner of an APPLE laptop could send him just the motherboard for repair, and so save on postage. He stopped this service about a month ago because it was fraught with dangers for his business. As Louis states, he can repair a motherboard but the owner of the laptop can damage it whilst installing back in the chassis. There is also the problem of the motherboard not being the fault or an item connected to the motherboard damaging it. In both cases the repair will fail as either no fault was found on the motherboard or the repaired motherboard is damaged by the ancillary component that remained in the chassis. LCD problems can also be in the panel and not the motherboard. Louis now requires that customers not already known to him, provide the complete laptop for diagnostics. I agree that this is by far the best situation as I would not want to trust a person with unknown skills to refit a motherboard.19. Accepting boards from other repair centres ..... Customer Vs Contract work ?This was an interesting one. Louis carries out motherboard repair for members of the public and also other repair centres who cannot find a fault. The two types of ‘customer’ can be very different. A member of the public brings in a faulty laptop for repair. It is virgin and has not been messed with. In the case of fluid contamination, Louis can see evidence of where the fluid has contacted the motherboard. From these visual keys he can often affect a repair quickly. The ‘Other’ repair centre ‘too difficult’ jobs that come into Louis are a completely different scenario. Louis receives the motherboard and often finds that another Technician has ‘had a go’ at it. This can mean various chips have been replaced or ‘heat-gunned’. It can mean more damage has been done through poor soldering skills or accidental shorts during measurements etc. It becomes quite an unknown package to unravel. The boards have also often been placed in an inappropriate type of ultrasonic bath, and for too long. The result of this is removal of all useful fluid contamination evidence and damaged solder joints through excessive ultrasonic exposure. A bit of a nightmare. This is why Louis will often prioritise one of his ‘walk-in’ members of the public higher than ‘contract’ work. He can likely repair the ‘walk-in’ faster and so repair more laptops per day, making more profit. The really badly messed up contract boards await his attention at quieter times.20. You can never have too much good flux !This is always worth repeatingSee No.1 !I hope this little collection of Wisdom from Louis has been of interest. It is certainly food for thought and as I am considering starting small scale Thermal Camera repair in my retirement , I have found much of what Louis says pertinent. Not sure I want to deal with the public or even other repair centres now !Fraser

author: Mr.B
author_rank: Unknown
timestamp: February 18, 2016, 07:04:28 pm
content: Thank you Fraser.I agree with the vast majority of your complied "Wisdom from Louis".I have watched a couple of his videos.Clearly I need to watch a few more...

author: mjwreno
author_rank: Newbie
timestamp: February 18, 2016, 07:22:06 pm
content: Thanks Fraser. This must've taken a while to right up, so appreciate it and will check out the channel. Very useful.Sent from my Q5 using Tapatalk

author: Fraser
author_rank: Super Contributor
timestamp: February 18, 2016, 07:43:49 pm
content: It did take while but I thought it worth the effort.I exceeded the forum post 20000 character limit, hence the split post.Fraser

author: Cubdriver
author_rank: Unknown
timestamp: February 18, 2016, 10:59:24 pm
content: An excellent summary, and I too enjoy his videos.-Pat

author: Towger
author_rank: Super Contributor
timestamp: February 19, 2016, 06:18:32 am
content: You have missed his latest video, which demonstrates why not to leave food on one's workbench :-)

author: Fraser
author_rank: Super Contributor
timestamp: February 19, 2016, 06:53:08 am
content: Just saw it. You can always count on a mouse to find food if you leave it out in the open. The nasty problem is that the mouse pee's as it searches so you get a smelly and sticky workbench !

author: zapta
author_rank: Super Contributor
timestamp: February 19, 2016, 06:59:11 am
content: Quote from: Fraser on February 18, 2016, 06:53:11 pmHe is cleaning with ultrasonic cleaner so cleaning is easy for him.

author: EEVblog
author_rank: Unknown
timestamp: February 19, 2016, 07:13:42 am
content: Quote from: mjwreno on February 18, 2016, 07:22:06 pmYes, a lot of work, nice one Fraser

author: HackedFridgeMagnet
author_rank: Super Contributor
timestamp: February 19, 2016, 07:36:21 am
content: After watching one of his videos I have tried to move more to a "4. Solution based charging as opposed to component based charging."And I also try to keep the 5. Discount ...... Why? in the forefront of my brain when I calculate price.I don't mind his "in you face" style.I should watch more of his videos as I have been quite influenced by the few I have seen. When time permits.

author: vze1lryy
author_rank: Regular Contributor
timestamp: February 19, 2016, 04:53:29 pm
content: Wow. I'm speechless!One thing I will say - thenightschoolI attended for board repair amounted to, instead of going home at 8 PM when we close, me sitting in my office until 1 AM or 5 AM sitting with a board and schematic analyzing, measuring, and looking for patterns and just probing around to try and figure out what was going on. I am a college dropout and failure - two time fail-out, one time drop-out, and I cheated on my chemistry regents to get through high school... so I sincerely hope people don't look to my content as a source of 100% accurate scientific knowledge, because it is far from it.

author: Lightages
author_rank: Unknown
timestamp: February 19, 2016, 05:01:02 pm
content: Yes Louis, you have a good attitude IMHO too. I enjoy your videos and have learned from them. I don't think you are brash, just open and honest. Thanks for sharing what you have learned.

author: Cubdriver
author_rank: Unknown
timestamp: February 19, 2016, 05:06:11 pm
content: Quote from: vze1lryy on February 19, 2016, 04:53:29 pmI get the funny feeling that THAT'S a rare occurrence!Having done it the hard way probably gives you a really good feel for what's happening on the boards, and is doubtless a huge help in your troubleshooting.Keep 'em coming.-Pat

author: Fraser
author_rank: Super Contributor
timestamp: February 19, 2016, 05:09:38 pm
content: Louis,You may have dropped out of college but you have the intelligence and a rare level of self discipline to teach yourself how a laptop works through practical test and measurement. It's a steep learning curve and your level of competence reflects how seriously you take your job. Apologies for assuming you went to night school. That is the more common path in the UK.The fact that you trained yourself using schematics and real world experience has led to your superb understanding of these motherboards. I take my hat off to you. As stated previously, thanks for the videos and effort you put into their content.Your efforts and real world experiences are both enjoyable and greatly appreciated. As I said, you are a self made businessman running a successful service centre.I would also like to say that this forum lead me to your YT channel so I am grateful to the OP who posted your video on reflowing GPU's. Hopefully this thread will also lead others to your excellent channel.I liked your CCTV coverage of the furry visitor to your workbenches as wellOh and my wife is getting used to hearing you talking in the background as I watch yet another of your many varied video's. She laughs and says...... First an Australian Accent all the time (Dave Jones) and now an American accent !I showed her your workbench layout today and she wanted to know why mine is not so well organised !I also bought a decent soldering fume filter this week after noting your common sense decision to use one.Take Care of yourselfFraser

author: Fraser
author_rank: Super Contributor
timestamp: February 20, 2016, 04:14:07 pm
content: I forgot to mention....... Louis is a fellow cat guardian. A cute black cat named Clinton. There are a couple of videos on his channel.That makes him OK by mePeople who do not like cats were mice in a past lifeBut seriously, my little cat, Oliver, got me through some pretty dark times when I was ill. Great for stress relief.Fraser

author: Radio Tech
author_rank: Frequent Contributor
timestamp: February 20, 2016, 04:33:08 pm
content: Very nice research Fraser, well doneI agree that had to take a while to do.Louis,I recently subscribed to your channel which was found from this forum.I too have dealt with public consumer repairs many time at different jobs.I don't find you to be harsh, but a caring confident repair tech that deals with consumer rants and tweaknicians with a golden soldering iron that do not have a clue what they are doing.Keep em coming

author: dannyf
author_rank: Super Contributor
timestamp: February 20, 2016, 04:43:59 pm
content: QuoteI find it amazing that someone can find a living repairing electronics today.

author: vze1lryy
author_rank: Regular Contributor
timestamp: February 20, 2016, 08:51:29 pm
content: Quote from: dannyf on February 20, 2016, 04:43:59 pmI am as surprised as you are.

author: KL27x
author_rank: Super Contributor
timestamp: February 22, 2016, 07:18:04 pm
content: QuoteThis was one of the first videos I saw of his. And this part was pretty disappointing. I think this part of his video is not very objective, at all. The speed of chip removal depends completely on what setting, air flow, and nozzle you are using. It doesn't matter how much you spend on the station. There is no amount of circuitry or firmware that can make one heated stream of air any different than another stream of hot air. Tighter temp control to say within a degree or two, versus a degree or four, won't make one remove chips faster than the other. Using different settings will. Later I see an earlier video where he shows his Hakko, with no temp indicators, just a 1-10, and how that is all you need for hot air. So he maybe knows this is a worthless comparison as he is doing it. His unboxing vid and commentary is mostly just hot air.Removing a couple of chips on camera with two different stations and timing and making comments on it is not a comparison of anything but personal bias. A proper test of different hot air stations would measure the warmup speed, the temperature consistency of the hot air, the maximum temp at the same airflow before the handle gets to hot or the station tops out, and perhaps some measure of maximum air flow and what temps can be reached at that maximum. The whole remove a chip under video wiht a random tip and unknown settings using stations which one is not familiar with at all is just a gag. After doing some objective testing or getting used to a station for awhile, maybe you can make some kind of useful observation.His use of $20.00 a tube BGA sticky flux on SMD passives is also just personal bias, and in one video he explains that it is more or less just the first flux he used that worked well, after trying other $20.00/syringe fluxes. If you do a lot of BGA, it makes perfect sense to use the same flux for everything, so long as it works. This isn't a knock on his practice. But some people seem to think this flux is special because Rossman can replace 0402 resistors, lol.

author: Fraser
author_rank: Super Contributor
timestamp: February 22, 2016, 08:10:48 pm
content: Louis is a repair specialist so I can forgive him not being a slick presenter of test equipment reviewsI agree though, to compare two or more hot air stations can be best done testing air flow, temperature accuracy and general build quality/ergonomics.The interesting difference between hot air stations that I have noted is the quality and power of heater used.My cheap Chinese hot air stations use a pretty horrible 'birds nest' heater element. It is rated at 250W. I have seen more powerful hot air stations coming out of China in recent years. They are rated at 500W, 550W and 800W. The heater elements in these higher powered units appear to be of better build quality and tend to be a spiral element would as a spiral on a ceramic former.My industrial PACE ST300 hot air station is fitted with a 600W heater element that, though nice quality, costs a whopping £400 as a spare part ! I have just ordered a Chinese 550W heater to experiment with as my other PACE hot air station needs a new heater.A hot air stations performance depends upon quality of air flow, heater design, temperature stability and ergonomics. More expensive industrial grade hot air stations are more likely to heat up much faster, provide a good constant flow of well managed hot air, no matter which nozzle is used and importantly, they will be built to last with excellent reliability. An important factor for industrial users.For a hobbyist, there is no great need to spend a fortune on a hot air station beyond ensuring that the model chosen is safe and performs OK. Slower warm up time can be tolerated. An industrial user does benefit from a faster time to working temperature though. I believe this, combined with reliable performance is what Louis likes about the two more expensive hot air stations. Both the Weller and JBC are quality products so it is no surprise that both work well.I also own a OK Industries SMT1600 hot air pencil. As many will know, a hot air pencil is all about precision. It is designed for working in heavily populated areas of PCB's and for heating individual pins or components without causing overheating to those around. I did see Louis using such a hot air pencil to remove a long connector. It did not work well as the hot air pencil is a bit like a tack hammer versus a sledge hammer when it comes to hot air working. A precision tool with relatively low power but very concentrated air jet. It is all horses for courses really.Fraser

author: Monkeh
author_rank: Super Contributor
timestamp: February 22, 2016, 08:34:37 pm
content: Quote from: Fraser on February 22, 2016, 08:10:48 pmHaving had fire shoot out the end of them, appearances can be deceiving!

author: Fraser
author_rank: Super Contributor
timestamp: February 22, 2016, 09:05:57 pm
content: Na, that's the added BBQ Charcoal starter mode 😆

author: amwales
author_rank: Regular Contributor
timestamp: February 22, 2016, 09:06:37 pm
content: LouisThankyou for sharing your videos, the passion you demonstrate is both infectious and inspiring.Angelo

author: vze1lryy
author_rank: Regular Contributor
timestamp: February 23, 2016, 03:02:25 am
content: Quote from: KL27x on February 22, 2016, 07:18:04 pmI could do a test with thermocouple and timer, a trainee and myself tried this while calibrating the WHA900 a while back, but man is that boring. I want to see how it actually works while I am working, lord is it boring to just look at graphs and tables of temps and times. What makes this channel doable for me is that I'm not going out of my way too far to make content. I'm just filming my regular workday. Finding a way to measure the circumference of the sphere of hot air coming out... that is a little too far out of the way for this. I'm not a lab, or trying to pretend to be one.The sheer amount of time it takes the WHA900 or the FR-801 to heat up to the temperature you set it to vs. the JBC is a big factor. For most of me working with the WHA900 I had the temperature turned up all the way. I find that I often have the temp turned up too high because it takes so long to reach max temp to begin with.Sit down at an FR-801 and a 10 layer PCB designed to absorb heat and an Atten 858D and a JBC JT-A and you'll see. I've been using the FR-801 for five years, the WHA900 heavily for four months, and the JBC JT-A for about three months. It's just another world. The fact that I can buy a 4mm or 6mm bent nozzle for the JBC, but not for the WHA900 is a big one as well. If you work under a microscope you will not be able to have the hot air pointing directly at the chip with the WHA900 which is something you're going to see the results of in a real comparison and not in a lab test where they just shove a thermocouple in front of the nozzle and move it around.I don't have a bias towards JBC. I have a bias towards Hakko & Weller if anything, it's the equipment I started and grew up using. JBC is some pretentious brand with salespeople who come to visit you using proper language in new fresh white polo shirts. I was hoping the JT-A would lose.It's on my desk because it heats up fast and has a bent nozzle so I can better direct heat under a microscope. I love hitting the button and it just getting hot in 7 seconds. I used to turn on the WHA900 and take a piss before I could come back to replace an SMC.Now with a single layer PCB it's totally different, you can buy some $50 POS and get by with no issues at all. When I use the same 390c/75% I use for handling a large chip on a 10 layer board on a single layer PCB because I've forgotten to change the profile, the solder stays molten for 30 seconds after I'm done.With single layer boards, most of what I discuss is totally irrelevant.The newer stations like the Hakko FR-810 heat up considerably faster than the old ones. The big differentiater for me in stations is how fast it heats up. I don't want to keep it on at 700-900f all day because that is a waste of heating element and electricity. At the same time, it really changes the way you work when you know that if you want to test a theory by replacing a chip, you are going to wait 7 seconds for your tool to be ready rather than 45. It just opens up the workflow and makes me a lot less "lazy."Again, if you're working on an assembly line where the station is on all day, doing the same shit all day, it doesn't matter at all. If you're switching back and forth between testing, measuring, staring at schematic, running wires, and replacing SMD components, you aren't going to have the hot air on all day.You COULD keep the Weller WHA900 on all day - but the difference in electric bill will eventually compensate for the difference in price. And no bent nozzles for sizes over 2mm.

author: rstor22
author_rank: Regular Contributor
timestamp: July 06, 2016, 09:19:23 pm
content: Quote from: Fraser on February 18, 2016, 06:53:11 pmWould there be any concerns about the liquid IPA being conductive and being applied while the board is powered on?

author: Cubdriver
author_rank: Unknown
timestamp: July 06, 2016, 10:11:13 pm
content: Quote from: rstor22 on July 06, 2016, 09:19:23 pmAt the voltages involved I wouldn't worry. I'd be less inclined to try it on a tube circuit with a 300 or more Vdc B+ rail, but on things less than 40-60 V or so would not be concerned.-Pat