New to Rework Stations - Page 1
Forum section: electronics / beginners

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: October 22, 2014, 11:59:57 pm
content: I picked up a Aoyue 6028 for pretty cheap in order to get me started with smd work and also to BGA my 2 Xbox 360 back to full health...Here are a couple question1-What better liquid or paste flux??2-Are there any brands of flux I should buy or stay away from3-Chip qic make a no/clean flux paste and is it any good ??4- Does solder paste go bad5-What tools do I need for BGA???6-Do I need different tips7-Anyone ever use a Aoyue 6028?Here she isThanks

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: October 23, 2014, 07:07:25 am
content: I can only answer a few of theseLiquid vs paste (gel) flux. Personally I prefer gel flux because it only leaves residue in the area you applied it, whereas liquid flux will flow and drip over a board, drying out as it spreads thin, leaving residue everywhere. Gel flux also helps to hold components in place before being tacked downNot sure about what brands to avoid, but I and many others use Kester brand fluxYes solder paste does have a shelf life. If kept in a fridge it will last ~6 months before deteriorating, if left in ambient temperature it will last about a week. When the paste deteriorates the flux and solder balls will separate, mixing may help in this case, as well as adding flux. If you're going to add additional flux do it in a separate container so you don't contaminate the original.

author: the_memristor
author_rank: Newbie
timestamp: October 23, 2014, 08:13:19 am
content: BGA rework can get very difficult if you have to reposition the BGA device. For this task you need very expensive rework stations etc...For getting your Xbox back to life it's necessary to get the floating balls connected again by heating up the BGA. In case of fine pitch soldering I personally like the fluid flux most, because it spreads over the chip equally. Especially for BGA devices the fluid ones will cover all balls under the package.Weller is a good producer for flux. It's not as cheap as the chinese stuff but it has a very good quality.

author: GreyWoolfe
author_rank: Unknown
timestamp: October 23, 2014, 11:17:50 am
content: I use MG Chemicals liquid flux applied with a syringe. Using a syringe or small squeeze bottle with a syringe needle on it(actually what I use now) gives good control and keeps the spreading to a minimum. It is easier to overapply with the squeeze bottle so some care is needed when dispensing until you get comfortable using it. You have more control with syringes. I also cut the tips off of the needles as the beveled end makes for a larger hole and a messier dispense.

author: nanofrog
author_rank: Super Contributor
timestamp: October 23, 2014, 05:38:38 pm
content: Flux:1. Get good quality, name brand supplies (applies to solder and wick too). Names like Kester, MG Chemicals (they sell their Rosin 835 in smaller containers, so it's very handy for hobbyists IMHO), Multicore, Indium, AIM (American Iron and Metals), and Chemtronics (wick) for example. Chip-quik is also good for both gel flux and solder paste. You'll save yourself a lot of aggravation this way.2. Liquid v. gel/paste, it's more application & personal preference. For example, some prefer gel for drag soldering, as liquid can run all over if not controlled. Toss say a refillable brush pen into the mix, such as aBonkote BON-102, and the control is attainable to the point personal preference may take precedence. There's also needle bottles, brush bottles, refillable flux pens (plastic or felt tips), or even dipping a brush into a well of flux. Lots of methods to apply it that can control the covered areas.3. In the case of BGA, I'd also recommend liquid for the same reason asthe_memristor(flows under all of the balls). This assumes you won't be using paste, but actually use a reballing jig. The jig and solder balls aren't expensive, but it's a PITA IMHO (but I see BGA as a PITA in general, especially for hobbyist use).Other:4. Solder paste does have a shelf life and storage conditions, so read the datasheet from the manufacturer.5. Vacuum pen and tweezers will help you place and manipulate the chip. You don't need to go crazy here, just a cheap pen and a couple of tweezers, say #5 & #7 can do a lot, and not just with BGA.6. Round nozzles will do for most anything. Check youtube for some videos on BGA using a hot air station for technique. Specialty nozzles have their place, but are primarily time savers, not absolute necessities. Shields help, which you can make out of disposable aluminum pie plates, turkey pans, ... you can find in kitchen sections of your local superstore (dollar stores are great for these).

author: flolic
author_rank: Frequent Contributor
timestamp: October 23, 2014, 05:57:58 pm
content: Quote from: TorqueRanger on October 22, 2014, 11:59:57 pmYou will not be able to rework big BGA as is xbox GPU with that hot air station.

author: made2hack
author_rank: Frequent Contributor
timestamp: October 23, 2014, 08:37:58 pm
content: To everyone,Why are GPUs being reworked? I see stencils for sale all over ebay and BGA reballing kits, but why is everyone reballing their GPUs (especially on laptops)?What has occured requiring this procedure?Regards,

author: RobertHolcombe
author_rank: Frequent Contributor
timestamp: October 23, 2014, 10:03:58 pm
content: Thermal cycling of the product stressing and eventually breaking the solder joints, resulting in intermittent solder jointsIts more common in compact products like laptops and gaming consoles, because they run hot by nature, but often aren't properly ventilated during use by the end user

author: TorqueRanger
author_rank: Frequent Contributor
timestamp: October 24, 2014, 02:41:39 am
content: Thanks for all you help guys ... Ok with fixing my xbox am I better off with using a small or med round nozzle or get the chip size tip ??Are alternative to soldering paste ?? Is there anything with a more of a shelf life than solder pasteThe reason I ask cause I have no local electronic stores,so everything has to be ordered ... Oh my stations comes with one tip and are there certain tips I should get or needAlso am I better off modding the rework station for a digital temp display or is that not necessary ?? Should I get a couple remote temp sensors since I only have a infrared temp probe for R/C cars and not sure the accuracy and where can I get a couple for cheap and will they last??Am I missing something?As far the BGA stuff I have a couple boards I can practice on..Quote from: flolic on October 23, 2014, 05:57:58 pmI am trying not to sound rude but why can't II see alot of people doing and I know there is alot of prep work to do in order to cause any problemsQuote from: nanofrog on October 23, 2014, 05:38:38 pmThank you so very much for the help out and I glad you said good things about MG chemical and Chipquik ... Cause I can get syringe for $13.00 with free shipping but not sure if thats a good price or not???Quote from: GreyWoolfe on October 23, 2014, 11:17:50 amThanks and I was thinking about checking MG chemicals cause they are all over ebay and was not sure the quality??Quote from: the_memristor on October 23, 2014, 08:13:19 amQuote from: RobertHolcombe on October 23, 2014, 07:07:25 amThanks

author: nanofrog
author_rank: Super Contributor
timestamp: October 24, 2014, 04:28:35 am
content: Quote from: TorqueRanger on October 24, 2014, 02:41:39 amJust get round nozzles of a few different sizes for hot air work, as you can do most anything with them once you get your technique down (may take longer than the specialty nozzles).Quote from: TorqueRanger on October 24, 2014, 02:41:39 amIf you're after solder paste, then no. It's not that it actually outright goes bad (i.e. chemistry degrades to the point it doesn't do it's job), but rather the metal solder powder/micro balls settles out of the flux when it becomes no longer viable (i.e. get flux, but not enough solder or vice versa).If you want to use reballing instead (youtube videos on reballing BGA), that's just balls of solder in a jar at the rated size (those numbers aren't arbitrary). You add the flux separately. And the flux you'd use will have a longer shelf life than solder paste (it can degrade over time, but it's not like the instant a date code printed on it expires and it's suddenly rendered absolutely useless).Some manufacturers don't place date codes on their flux, and it's rare to find it on solder wire. Kester is one that does on both. Doesn't mean it's instantly useless when the date expires, just that they don't guarantee it's performance (flux performance can degrade over time, particularly if it's stored poorly, say in a hot garage for years). Store it indoors at room temperature, and it won't be a concern for hobbyist use.There's also a difference between paste flux and solder paste. Solder past adds very fine metal balls of solder alloy to paste or gel flux.Quote from: TorqueRanger on October 24, 2014, 02:41:39 amIf it's hot air, they're called nozzles. Tips refer to an iron. Confusing if you interchange terms.Quote from: TorqueRanger on October 24, 2014, 02:41:39 amNot necessary.Quote from: TorqueRanger on October 24, 2014, 02:41:39 amHuh? What exactly are you trying to measure the temperature of, and why?Trying to measure component temperatures while soldering with hot air for example?Quote from: TorqueRanger on October 24, 2014, 02:41:39 amMG Chemicals is a top tier manufacturer. A particular product may not be the absolute best, but it's going to be close.For example, I prefer Kester's 186-18 to MG Chemical's Rosin 835, but Kester's smallest container is 1 gallon. So it's not really hobbyist friendly like the smaller containers of Rosin 835 are (100ml & 1 L). There's the disposable pens of course, but they're expensive. Much more economical to get liquid flux in a bottle and use it in a refillable dispenser of some sort.

author: Szewczykm
author_rank: Regular Contributor
timestamp: October 24, 2014, 10:02:34 pm
content: I've had a 500mg tub of kester solder paste, scooping out what I need every couple of months. It's been in the fridge for over a year and it still seems fine to me. I've had a syringe of it sitting on my bench at room temperature for over a month now and it's still working great.I've used cheaper solders that did separate after a while at room temperature. So I guess it has to do with the quality of what you're buying. I only buy Kester solders anymore.

author: Softboxdz
author_rank: Contributor
timestamp: October 23, 2021, 01:40:50 am
content: Hey . For the flux I work with amtec 559 paste …. And I don’t think you are able to reball your xbox Gpu with just a hot air station ..You need a lot of equipment to do that1 Bga rework station2 stencil3 solder balls4 advanced skills5 advanced skills …..You can reflow it if the solder joints are in fine condition