Electronics Forum | Wed Jan 16 11:20:52 EST 2002 | bentzen
Hi... We tend to do a lot of footprint calculating for new SMD components. But what about the amount of solder paste on the solder pads. The amount of solder alloy is of cause determined by the stencil aperture size, stencil thickness and the sold
Electronics Forum | Tue Sep 22 10:29:18 EDT 2009 | stepheniii
To how many decimal places? Do you want to have a factor for different screen printer operators? There is no such formula and I doubt there ever will be one with any real accuracy. The stencil house might be able to tell you the total area of the
Electronics Forum | Mon Apr 12 15:52:12 EDT 2004 | wgaffubar
I am using Indium 92J type 4 solder paste due to a BGA site with .008" pads and stencil opening of .009" square and .005" stencil thickness. When I try the type 3 we get insuffecient print. The aspect ratio tells me that I should be using a type 4. T
Electronics Forum | Thu Mar 23 10:02:09 EST 2006 | Joe
Check placement pressure. I agree with the "smushing" theory. If you can place the component with less pressure, I'd do that first. A switch to Type three paste is also a good idea, as long as your minimum aperture dimension remains at 0.009" as you
Electronics Forum | Fri May 21 15:50:41 EDT 1999 | John Thorup
We are running a number of boards with 8-10 25 mil PQFPs on board. Our process is mature with at least 3 years experiance and statistically few opens on the QFPs. Our beloved purchasing department has chased the almighty $ and changed FAB vendors
Electronics Forum | Tue Oct 31 14:52:25 EST 2000 | Dr. Kantesh Doss
Hi Antonio: You clearly have printed excessive amount of solder paste on the pad. You can reduce the amount of paste by one or two methods: 1. Switchover to 5 mil thick stencils. 2. Change the design of your stencil openings (at the discrete compone
Electronics Forum | Wed Apr 16 16:55:38 EDT 2003 | russ
Thanks for the info, Here is a couple more questions (and you thought you were done) What size are these caps /res? how thick is your stencil? what type of oven are you using? what is the finish of the board? Anyway, it seems like (from a distance)t
Electronics Forum | Thu Aug 10 13:16:17 EDT 2000 | Bob Willis
Here is some thing that I wrote a while back on solder beading. First what is a Solder Bead? The term solder bead is used to differentiate it from solder balls. A solder bead is a solder ball but its location is normally constant unlike solder bal
Electronics Forum | Sat Mar 18 02:21:31 EST 2006 | pavel_murtishev
Good morning, Once again a met annoying solder beading issue while producing board with PLL (leadless, contacts from the bottom side of the package). Board has very high placement density and beads appear near PLL package only. This package is finep
Electronics Forum | Wed Sep 19 11:50:02 EDT 2007 | stepheniii
nevermind misread the post. But if the silkscreen is too thick, can you switch to another PCB manufacturer?