Electronics Forum | Tue Apr 26 18:23:30 EDT 2005 | russ
How does your machine recognize the part? Does it use vision for ball inspection or a just a body scan? What is the aperture size on the stencil? Have you calculated the area ratio? What is the aperture shape? What type of paste are you using? is
Electronics Forum | Mon Jan 22 12:55:53 EST 2007 | russ
Volume req'd for pih is 2.2 x the hole volume after lead has been inserted. Stencils work quite well in PIH applications too if you can make aperture large enough. Slow squeegee speeds also aid in filling hole with paste. Russ
Electronics Forum | Thu Mar 03 18:09:06 EST 2005 | gpaelmo
We also use Indium NC-SMQ92J. We do the same as mentioned per Russ. We reduce apertures mostly on QFP's with pitch of 25 mil or less (we place down to 15 mil QFP). All other apertures we keep 1:1. We print resnet 0805 size with no problems. You might
Electronics Forum | Thu Jun 13 11:25:40 EDT 2002 | davef
Help us understand your situation by telling us about: * Is this a terminal-to-terminal short on a single MELF? Or is this a terminal-to-terminal short between or than one MELF? * Clearance of 0.8mm is the distance between what features? * Size ME
Electronics Forum | Thu Dec 20 12:05:46 EST 2007 | realchunks
Not you Steven. Blanket comments like "Double pass printing for solder paste is not needed and will cause defects. Redesign your stencil thickness or aperture sizes, change your paste mesh size or type, go to 45 degree blades." are so way off base.
Electronics Forum | Wed Jan 11 11:52:50 EST 2017 | emeto
First, why do you have paste on the opposite side of the component. I would recommend having it on the same side. Second, how thick is your stencil? Pin in paste requires thickness, to fill the whole barrel. Stencil should be really thick. Try to man
Electronics Forum | Wed Feb 28 11:43:20 EST 2007 | realchunks
Marcin, Think outside the box. If you are glueing the SMT part down, why not have an aperture cut in your stencil (or recut a stencil) between the SMT part and thru-hole. Wave solder hates SMT glue. This will get rid of your solder short problem
Electronics Forum | Thu Apr 24 23:04:45 EDT 2003 | yukim
I've been struggling with this problem for a while. We have two products: A, which is Ok and B, with tombstone defect (0603 & 0805 capacitor chips). A & B have the same design: pad sizes, separation between pads, components orientation. Both have s
Electronics Forum | Thu Aug 12 22:38:44 EDT 1999 | Dave F
| Hello | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | 100 durometer blade. Getting "tails" on deposi
Electronics Forum | Thu Nov 16 22:01:16 EST 2000 | Early Moon
I promised never to do this - BUT only for you needy folks when I have nothing else to do. And Dave's basically a good person though not as needy as most really needing this stuff. 1) Ensure internal Gerber data really matches board and stencil (Ger
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