Good solder balls?

[G.Beard]

Hi.

I'm having trouble re-balling GPUs with Sn63/Pb37 paste and stencil because I'm finding the stencils bow. The bow in the stencil is giving me uneven balls. After the 4th attempt I may get them right but it's not the best way to spend my time. I have an idea that using ready made solder balls might be the solution.

Can anyone recommend me some good solder balls?

 

[aprendiz]

PMTC or Qwin, I've been using any of those since i´ve started.....

 

[dukefawks]

Reballing GPUs? I hope you are not reusing old garbage? Any leaded balls should be fine, just get a bottle with 250K balls.

 

[dukefawks]

Why are you taking it up to 230C with leaded balls? Just let the temp ramp up until the chip settles and floats then turn off the heat. I never use profiles. Just make sure it ramps up to reflow in <2 minutes or the flux will be gone before reflow temp is reached.

 

[G.Beard]

Why are you taking it up to 230C with leaded balls? Just let the temp ramp up until the chip settles and floats then turn off the heat. I never use profiles. Just make sure it ramps up to reflow in <2 minutes or the flux will be gone before reflow temp is reached.

Sorry, typo. corrected now (un-leaded).
No profiles?... Hm, OK I'll play with that on some donor boards.