Electronics Forum | Wed Feb 05 13:56:40 EST 2003 | davef
I figure if you need the rest, you don't need these. These strips are from some laser cutting tool fabricator. They give them to their customers [laser cut stencil fabricators] so the customer can do a good job. Yall have a nice day now, y'hear?
Electronics Forum | Mon Jul 18 10:55:26 EDT 2005 | Sylvain
I have a SO-8 mosfet part from Vishay SI7846DP-T1. Am having a lot of solder ball that coming underneath the part. Am currently using a 5 mils with a window design for my stencil. Those anyone have experience or have any suggestion for an aperture th
Electronics Forum | Thu Jul 21 09:43:10 EDT 2005 | davef
We agree with Russ. The solderballs are probably the result of printing too much paste on the board. In designing your 5 thou thick stencil: * Aperatures for the pads should be identical to a IPC-7351 - SO8 [or worst case http://www.vishay.com/docs
Electronics Forum | Thu Feb 08 14:55:30 EST 2007 | pavel_murtishev
Good evening, I do. 2mil overprint is not critical. Paste will simply flow back. Paste flows back even with larger overprint (up to 15mil at least). 5mil stencil thickness if fine also. BGA area ratio for both BGAs is higher than 0.66 required by IP
Electronics Forum | Fri Feb 15 11:23:44 EST 2008 | realchunks
Print material through stencil onto Plexi-glass and place Plexi onto your board. Sure, it may cause a little clean up but this where the metal meets the meat. Don't worry about ESD cause you have no component on the board yet (sorry Quality guys -
Electronics Forum | Wed Feb 20 15:00:12 EST 2008 | mulder0990
Reading the original post.. Floyd, do you remember the old overhead projectors back before we had the new fancy video projectors? Just get a clear sheet of that plastic and print your outline on that. Put that sheet over the stencil and presto, you
Electronics Forum | Sat Aug 22 16:16:13 EDT 2015 | davef
Comments are: * Read “Challenges for Step Stencil Printing” [Carmina Lantzsch, Georg Kleemann, LaserJob GmbH] http://www.smtnet.com/library/index.cfm?fuseaction=view_article&article_id=2096 * I want to say that IPC7525B [Oct 2011] improved the dis
Electronics Forum | Wed Jul 18 17:09:45 EDT 2018 | slthomas
Update - next run started out horribly so went to another stencil design. Reduced thermal pad coverage by about 40% with 4 panes, with cutouts to avoid the vias. Worked like a charm for 10 boards (90 parts). I think we're finally on to something.
Electronics Forum | Mon Feb 10 10:23:53 EST 2020 | emeto
Solder paste has stencil life time - if you go over it means you should change it. If you print boards in front and keep them for too long before reflow, the flux is still evaporating, so you are not mitigating the risk. Paste also likes room tempera
Electronics Forum | Tue Feb 11 14:37:26 EST 2020 | spoiltforchoice
If you're asking me, I'm using BLT LFS-UFP-T4 (they have an even better paste to treat badly now if you add zq). Those in the test of the world might find Loctite GC10 is similar, however the stencil and tack times on the BLT are pretty awesome and
