Electronics Forum | Mon Sep 19 01:57:28 EDT 2016 | shriram
Hi guys, Problem: Mid chip solder balling. Component affected: 0603 caps only Defect is PCB specific (Meaning only one PCB is affected as the aperture is standard for that component). As a containment I'll give a home plate design for the compo
Electronics Forum | Tue Feb 04 09:03:45 EST 2003 | Russ Roberts
Greetings, I am pretty new to SMT production, and have learned much from this forum. I am getting ready to build a CCA with many 0402 parts that are really close together. I consider these fine pitch. The board also has two QFPS, so my stencil design
Electronics Forum | Fri Nov 30 08:53:17 EST 2007 | jaimebc
Shy, Our 5 and 6 mils stencils have home plate apertures and reduced by 10% and using SMT adhesive. Never had a problem with components non wetting like you have. I do believe that you are not screening enough paste, something about the dog bone ape
Electronics Forum | Wed Nov 10 18:02:54 EST 1999 | John Thorup
Hi Dave Sounds like what we call a "squeeze ball". Usually caused by excess paste squeezed over the mask between the pads of the component when placed. This sometimes escapes the pull of surface tension back to the fillet and escapes to the side, us
Electronics Forum | Tue Jun 27 11:16:33 EDT 2000 | Christopher Lampron
Hello Bill, Ioan's idea's are good. One more thing that you may want to consider is using a "Home Plate" aperture on your stencil for the aforementioned caps. The idea is to put a smaller amount of solder paste directly underneath the component. This
Electronics Forum | Fri Dec 17 01:21:54 EST 1999 | Victor Salazar
Weare using a Home plate design on 1210 or larger, 20% reduction on pkgs from 1206 to 1210, 10% reduction on 1206 or smaller, 0 reduction on all leaded components(sot-23, IC's) with a 6 mil stencil. For fine pitch we are using 4mil stencils. We h
Electronics Forum | Wed Aug 05 20:48:50 EDT 1998 | Ron Costa
I'm currently running a double sided paste smt board loaded with 0603's, on the secondary side. Many of the 0603 devices tombstone during reflow if the parts are not perfectly centered on the pads. Is this caused by the .008 foil thickness? Has anyon
Electronics Forum | Mon Aug 14 14:27:00 EDT 2017 | emeto
Here is some food for thought. Try to answer these questions yourself and I am sure you will see huge improvement. Reasons: - Bad PCB design - Plating-uneven HASL cause more than OSP Au/Ni or Silver - Poor paste and print quality - uneven paste ca
Electronics Forum | Fri Aug 07 10:14:43 EDT 1998 | RWW
| I'm currently running a double sided paste smt board loaded with 0603's, on the secondary side. Many of the 0603 devices tombstone during reflow if the parts are not perfectly centered on the pads. Is this caused by the .008 foil thickness? Has any
Electronics Forum | Wed Jul 03 07:40:48 EDT 2002 | Yannick
Hi, WE are making some test with this kind of component and aperture and here what we think. when you use a home plate aperture it's seem that the component is not lenght enought to have a good solder but maybe is our CAD guy that didn't make a
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