Electronics Forum | Wed Jan 30 03:01:39 EST 2019 | robl
You could use a stepped stencil around the parts you're having issues with to add a greater paste deposit to them and not the rest, or slightly elongate the apertures and overprint, but this may lead to solder balling.
Electronics Forum | Mon Sep 30 02:47:47 EDT 2019 | robl
Hi Scot, What X-ray machine are you using? that's a pretty good image. Thanks, Rob.
Electronics Forum | Mon Sep 30 09:58:47 EDT 2019 | scotceltic
I am not quite sure. The analysis came from our sub-supplier. I can find out though. I agree it is a very good image.
Electronics Forum | Wed Nov 13 12:06:53 EST 2019 | slthomas
The answer is usually either too much paste or paste being deposited where it doesn't belong. In some instances the two are related. You don't say what kind of parts you're having problems with and that matters too. I agree with the previous poste
Electronics Forum | Mon Nov 18 02:44:33 EST 2019 | pate2418
Did you reduce the apertures in the stencil? There can also be very large contact SMD pads. Can be the wrong the thickness of the stencil (thicker than need)
Electronics Forum | Thu Apr 30 23:21:52 EDT 2020 | SMTA-Davandran
I am seeing a lot of solder ball for PIP process. is it due to the paste height go beyond 0.2mm.? what is the DOE need to focused for PIP process?
Electronics Forum | Tue Apr 27 19:13:04 EDT 2021 | astarotf
Solder balls, can be excess paste by opening ST. Do you see the curve still working pasty with lead with alloy "63Sn / 37Pb alloy" has defects?
Electronics Forum | Fri Apr 30 19:22:57 EDT 2021 | compit
After printing or after the oven? Too much paste - thinner stencil, smaller holes, to rare paste ...
Electronics Forum | Wed May 05 06:30:40 EDT 2021 | jineshjpr
Do Proper underneath stencil cleaning. if the cleaning not effective, check Vaccuum section of the printer machine. Else change the Wipe roll. Trying out with other cleaning solvent (dedicated to stencil cleaner) also improve this issues.
Electronics Forum | Mon Aug 14 13:21:48 EDT 2023 | calebcsmt
the implication being the soldermask is too thick, raising the top of the board higher than the pads themselves (eliminating gasketing)? Essentially, the board isn't perfectly planar would be the subject of cause it sounds like?