Electronics Forum | Thu Feb 23 18:05:53 EST 2006 | kennyg
What are some general guidelines for the minimum proximity of apertures to a stepdown on a stepped stencil. I have a step from 7 mils to 5 (one mil step each on the top and bottom). How far does the step need to extend beyond the apertures on the
Electronics Forum | Thu May 20 16:22:07 EDT 2010 | remullis
I just got word from my board designer that the actual pad size is 11.8 mil and he is reducing the paste layer to 7.8 mil. To me this is way to much of a reduction. I am was accustomed to doing 20% reduction on any thing 20mil pitch or less. The scre
Electronics Forum | Fri Feb 03 09:50:37 EST 2012 | mosborne1
Thanks very much everyone. > > I'll try out a > 5mil and see how that goes. If you are using 6mil stencil and you are saying that you need more on the 0603 parts then you might want to look at your squeege pressure. What kind of squeege blades ar
Electronics Forum | Fri Jan 24 08:14:24 EST 2014 | davem
m_imtiaz, Over the last 15 years or so I've found that using the stencil foil thickness +2mils/-0mils has worked very well. For example, if you have a 5mil stencil thickness your upper control limit would be 7mils and your lower control limit would
Electronics Forum | Wed Dec 15 18:03:28 EST 2004 | russ
I have used both 4 and 5 mil stencils for 10 mil round apertures. We don't have volume measurement capability but we measure height and the 4 mil appeared to have more paste and better uniformity from a visual standpoint than the 5 mil. The unfortu
Electronics Forum | Thu Feb 08 08:28:11 EST 2007 | mzaboogie
Good Morning Everyone, We have an application coming up with several BGA's on a RoHS assembly. One is a 25 mil ball on a 40 mil pitch, another is a 15 mil ball on a 40 mil pitch. In the past for leaded assemblies, we have used square apertures for 1
Electronics Forum | Thu Sep 10 17:10:00 EDT 1998 | Steve Gregory
Hi Tim, 8-mil huh? Boy, that's getting down there...you know, placing 8-mil is one thing, but printing solder paste on 8-mil pitch is another. Most of the time when I've seen 8-mil pitch on a board it's been attached with hot-bar...but I guess
Electronics Forum | Thu Dec 17 10:25:19 EST 1998 | Earl Moon
| I have a mixed technology board ranging from 50 mil pitch devices to 20mil Qfp's to PBGA-352 at 1.27mm, and 6 Intel uBGA-48 at 30 mil pitch. With all these different package types i'm torn between using a 4 or 5mil thick stencil. The ball dia. is 1
Electronics Forum | Thu Jan 04 12:51:37 EST 2007 | Board House
Hi Chunks, Starting copper on outer layer with .0007 is 1/2 oz. copper foil. so if starting copper is .0007 and your Board house will plate an additional .0021 mils of copper. which will give you a finished copper weight of .0028 Mils or (2 oz.) Y
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
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