Electronics Forum | Tue Apr 14 20:28:03 EDT 2015 | carlosdugay123
Hello Marshall, I represent Metal Etch Services, we manufacture SMT Single and Multi-Level Stencils, we have over 25 years experience and one of the reasons most of our customers like us is because we offer technical assistance. Regarding the issue y
Electronics Forum | Wed Nov 15 12:52:21 EST 2017 | georgetruitt
IMO – Look into nano-coatings for your stencil and radius all square apertures This should help out with solder paste releasing from the stencil helping with insufficient solder QFN LGA aperture design, try a stencil cut with a few different apertur
Electronics Forum | Fri Oct 28 10:26:39 EDT 2005 | james
Kester water soluble seems to work best for us at this point. I am just trying to figure out why we are having so many problems when we use AIM paste. It tends to stick to the blades, clog the aperatures and of course gives us insufficient solder.
Electronics Forum | Tue May 31 11:56:12 EDT 2005 | chunks
Hi Matt, Get definitive answers! Contamination on the HASL finish?: From the pix you posted, it looks like something fishy is going on. I�d reject them back to the board house and demand an answer. Most board houses and purchasing people will g
Electronics Forum | Wed Mar 12 13:41:23 EDT 2008 | swag
We have a lead free assembly with a 128-Pin PQFP with 20 mil pitch leads. We have tried stencil aperture reductions, step-down stencils, different thickness stencils, various printer setting changes, placement pressure changes, nozzle changes, moved
Electronics Forum | Fri Mar 23 11:58:01 EST 2001 | mparker
You are mixing long exposed paste back into fresh? How long has your fresh jar been open to the air? You are probably doing yourself a disservice by scavenging the paste (it could have moisture entrapped). Your visocity has definitely changed. You a
Electronics Forum | Sat May 06 08:46:46 EDT 2000 | Dave F
Sal: Now you�re talkin�, buddy!!! Darrell is correct. All things being equal, thermal relieved vias (and through holes) should be the hottest spot on the board at reflow temperatures. Vias are gonna take on solder like drippin�s take to biscuits.
Electronics Forum | Wed Mar 18 11:27:24 EDT 2020 | slthomas
I am about to order a stencil and I can already see that I'm going to have issues. I'm hoping someone has a recipe for this scenario that we haven't tried yet. The parts are 16 mil pitch bga's, the pads are NSMD (10 mil dia. with 12.6 mil mask open
Electronics Forum | Thu Mar 22 16:06:22 EST 2001 | dblsixes
Our next plan of attack is to dog-bone the solder aperature. By reducing the width of the solder paste at the heel, we hope to slow the flow up the leg of the pin while the temperature of the pad catches up. We have boards that were HASL ...
Electronics Forum | Thu Mar 22 21:53:49 EST 2001 | davef
Don't mess with the doggie stuff until you get longer pads [and then you won't have to mess with it] because you'll just ruin your lead definition with more paste and still not have the heel fillet you desire.