Electronics Forum | Fri Jul 19 21:19:25 EDT 2002 | yngwie
Hi, I know this is a total screwed-up. Operator used the wrong paste. It was supposed to be a clean paste but she was issued with no clean paste. What happen was when the brd processed thru', after the reflow, the girl passed the boards thru' DI wa
Electronics Forum | Sat Jul 20 09:02:04 EDT 2002 | davef
Probably 2) what is this white residue material (chemically )? => Natural or synthetic rosin 3) Can Saponifier wash, helps? If not what is the best solution to remedy this white residue. => Probably a saponifier will work. Some NC flux residues
Electronics Forum | Fri Aug 24 13:21:59 EDT 2018 | babe7362000
What do others use as far as solder paste type, stencil thickness and aperature size for a .4mm Ball Pitch CSP. Ball diameter is .3mm. Please let me know your thoughts or what you use. Thanks
Electronics Forum | Thu Aug 30 13:06:10 EDT 2018 | emeto
I don't know your board, but for this specific part: 10mil round aperture on a 3.5mil stencil with type 4 paste wold be ideal
Electronics Forum | Wed Aug 29 03:16:20 EDT 2018 | cannizzaro
It is recommended that the thickness of the stencil of 0.1mm, the steel mesh should be partially nano-coated. It is best not to dry easily, and the particles are not easy to be too large. I have tried ALLPCB for this kind of BGA in the past and they
Electronics Forum | Tue Jan 20 08:38:37 EST 2009 | davef
MrDif: You don't add fresh paste to used paste? We add fresh paste to used paste on the stencil to replenish the paste consumed while printing boards, so that we maintain a nice thumb-size roll of paste. We change the used paste when we clean the ste
Electronics Forum | Wed Jan 21 03:34:05 EST 2009 | mrdtech
Sorry if that sentence there was not really clear. I meant: don't to try to 'revive' old paste or paste that has been on the stencil for a very long time using fresh paste.
Electronics Forum | Tue Jan 20 07:57:00 EST 2009 | mrdtech
Depends on the solder paste. If it has been on the stencil for 24h there is a good chance that the paste is destroyed. You can however check if it has not dried out too much by letting the stencil printer do a few strokes and see if the paste still h
Electronics Forum | Sat Jan 17 17:42:07 EST 2009 | viresh
what is the impact if a solder paste is used after 24 hours after tawing time
Electronics Forum | Sun Jan 18 09:20:26 EST 2009 | davef
We're not sure of the condition of your solder paste. So, afte 24 hours, if it's: * Unused, in a reclosed container, maybe a week of life depending on the environment * Used, scrap A simple coalescence test can quickly determine the condition of sol
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