BGA rework supplies - any suggestions for the good stuff?

[rx8pilot]

I am hoping to do some repairs that require BGA re-work. So far, I have watched a few dozen videos and read a number of articles on the web that cover the basics.

I already have the majority of the tools - SMT oven, microscope, hot air, etc, etc....but I need all the BGA specific supplies and fixtures. Balls, stencils, and holding fixtures. There is no shortage of this stuff on eBay, Amazon, Alibaba but I am not able to tell if those cheap kits are ok or just junk. I have a number of practice devices and boards but when it comes time for the real thing - I will be dealing with $300 parts. My preference to get some reputable gear and supplies to avoid a pricey experiment. My first project is a 729 ball device - perhaps a bit ambitious.

This will be a fairly occasional task, so I don't want to go crazy but going super low-end may just get me frustrated.

Is the cheap stuff just fine?
If not, who makes 'repair' quality fixtures, stencils, and balls? (for the occasional user that is hoping for a pro level reball)
Is this something that I am likely to regret (ie rabbit hole) that end with some expensive and big BGA setup that I only use 5 times per year?

[rx8pilot]

I would have expected all sorts of opinions on this topic 

I guess I will get a variety of options starting at the low end and see if I have any luck.

[PKTKS]

I would have expected all sorts of opinions on this topic 

I guess I will get a variety of options starting at the low end and see if I have any luck.

 

BGA sucks.  period.

Lack of opinion (or just delay)  because it is mostly a trial and error procedure

In the assembly line with all sort of gizmos (pre heated board, proper temperature/flux etc)
is one very simple thing - just pick and place and let go.. machines will take care...

On the bench is another thing - apart the proper  fixture to re-ball the chip and all
the other concerns like temperature - pre-heating the base - the flux (like AMTECH series)
to give you enough time to apply a "proper nozzle" air flow...

All this is more  or less trial and error - results in general are ok
Just don't cook the board and make no mistake of uneven balls...

Summary is that BGA sucks . it may be fancy and good to a pick place pre heat machine
but not on the bench - apart from getting all the ball fixtures you probably need

Hope helps
Paul

[Ordinaryman1971]

Well good eyes and even better ventilation is a must.
Buy microscope, you can't do most of this work without seeing the problem.
With stencils it's tricky, you buy what you need, if the one you need is included in the kit.. you buy the kit and... you have extras.
How big would be the chips you would work on. Bigger chip bigger gear.
I think I would start from cell phones, boards are smaller so you won't need that much power and heat and... all the stuff.
Try to make money on what you do, replace connectors, replace whatever and make a buck.
Buy bigger gear, get better ventilation.
Avoid headaches.

[Fred27]

QFN still frustrates the hell out of me, so I can only suggest the obvious. Get some cheaper and easier BGA components to practice on first!

[rx8pilot]

BGA sucks.  period.

 

I am only interested in this because I have access to a number of high-value pieces of equipment that have a reasonable likelihood of repair if I can swap various BGA parts that have been damaged. I don't think I would bother with iPhones or any other consumer product unless that was going to be a totally new business.

So far....I have been able to successfully remove a few 700+ ball BGA's and get them cleaned up. No damage to PCB or surrounding components. My plan so far, is to bake the donor PCB's for 6-8 hrs for moisture. Then bring them up to about 175C, pull it out of the oven add a protection mask, flux, hot air for a controlled removal without much risk of damage. So far, that is no problem. After that, I have delicately cleaned the BGA to prepare it for the re-ball process without any damage.

I am assuming that there are no options for re-ball where I would not need a stencil. The variety pack stencils may or may not work and I am not too sure where to get custom stencils. I do have a laser, perhaps I can use a generic stencil and cut a precision mask with the laser to avoid the cost and lead-time for a custom stencil to re-ball a single BGA.

The next big question is re-flowing back on to a PCB. What option are there to apply solder paste to the PCB (with all the components around it)? Can the balls on the BGA be enough, maybe just put a thin film of flux on the cleaned PCB pads?

[PKTKS]

There are options to re-ball likely even more than these

- top list - buy  a replacement chip already w/balls - there are plenty

- use the fixture you find (or can get) more proper to "re-ball" w/paste+gun

- buy some  packs of already made balls in a can...  hold breath and place them
 the option may seem silly at first but there are cases where you definitively
 will find better to replace a single ball w/tweezers than 100 or 200 ...

the list goes on..  summary - as always - all of them sucks.

In the worst case scenario a machine to place and do the proper thermal profile
will be required...  GPUs and CPUs and some other ASICs may require this option

It sucks - we will not get rid of that any sooner
Devices are getting insanely thinner .. compact and almost  unserviceable

last but not least..  wick the crap before you start...  a thin good wick will do it
Paul

[dnwheeler]

There are several videos on YouTube by iPadRehab, Paul Daniels, and Louis Rossmann (actually, his employee Paul is better at this than Louis) showing the whole process of removing the chip, cleaning up the old pads (on board and chip), re-balling, and re-soldering the chip. It looks like you have to be a bit of a perfectionist and be willing to start over to get the re-balling right.

[LeoG]

Does anyone know of a good practice board that I can buy for BGA practice? Or should I source some BGA chips and design/order own?  They don't have to actually do anything other then be testable to make sure there's no bridging.

[mrf245]

I was a engineer in PCB manufacturer few years ago, rework BGA.
First you need drying your PCB for several hours to avoid blister when reworking.
Second...just like all video and articles show the process. Aligning and temperature are very important.

Mark