Bga Stencil set and base? ,for Vram reballing.

[dreico33]

Hellow guys,
I am looking for a good set of stencils and bases(dont kbow exacly the word) for vram exclusive bga reballing.
Your recomendations are very welcome
Thank you.

[DynaxSC]

I'm not aware of existance of vram stencil sets. I buy usually dedicated stencils for dedicated vram chips. They cost generally peanuts on Aliexpress, so I just buy them looking only on the cost with delivery and on the reputation of the seller and number of sold pcs. Quality is generally good, but sometimes there are issues with more complex stencil, eg for Intel chipsets. With vram stencils I never had issues, they are not so complex. Buying general sets for everything in my opinion does not make any sense, its only shipping lot of metal with the airplane, cousing CO2 emissions, where you will then use maybe 5 of 100 you get in your lifetime.

Regarding the "Base" I reball vrams only with the small direct heating stencils, with a kind of holder with a spring. There are the bigger stencils 80x80 or 90x90 where you need a more expensive positioning tool, but In my opinion this make sense only for bigger chips, eg. GPU's or chipsets. Vrams are done faster with the direct heating stencils. But I may be wrong here. Nethertheless the cost of the positioning tool and the bigger stencils is much higher.

Anyway if you plan to reball lot of vram chips at once maybe it is better to use a tool with 90x90 stencil, preferably if you could work on more chips in the same step. Reballing 8 or 12 chips takes a lot of time. Doing it in one step would be much better. However I'm not sure if such tool + stencil exist.

Also a tip, some stencils need to be redrilled for a bigger whole, as the balls sometimes get stuck in the stencil due to thermal expansion during heating. I'm not sure, but either the stencils have too small wholes or the balls do not meet the correct dimensions, so sometimes there are issues with them. So buy always 2-3 pcs so you can experiment with them.