Electronics Forum | Mon Oct 15 10:51:49 EDT 2001 | davef
On over printing, the general issues are: * Paste deposits being so large that when reflowing, collapse onto many, rather than a single solder mass. * Paste expanding during heating and being close to other solder deposits and bridging [as you say].
Electronics Forum | Fri Mar 23 14:13:20 EST 2001 | mnaddra
RW, I have Screened Adhesive on to several different assemblies and have found that when it is possible I get a much better result than with a dot deposition process (The green strength was greatly improved), the biggest issue I ran in to was the pr
Electronics Forum | Mon Sep 17 15:27:51 EDT 2001 | jschake
Challenges: The basic defects that impact assembly yield are bridging, satellite solder balls, and opens (i.e. tombstones / draw bridges). There are many variables with the stencil printing process that can impact these; several of them are listed
Electronics Forum | Fri May 14 17:06:18 EDT 1999 | Ryan Jennens
| | Hi Guys, | | | | I am going to be graced with the good luck of processing microBGA's in the near future. A bit of a step forward from printing 20-mil pitch and wave soldering 0805's, wouldn't you say? | | | | So, any of you folks who have alre
Electronics Forum | Fri May 14 17:06:29 EDT 1999 | Ryan Jennens
| | Hi Guys, | | | | I am going to be graced with the good luck of processing microBGA's in the near future. A bit of a step forward from printing 20-mil pitch and wave soldering 0805's, wouldn't you say? | | | | So, any of you folks who have alre
Electronics Forum | Mon Aug 30 11:20:12 EDT 1999 | John Thorup
| | | Planning to evaluate the above process... | | | Can anyone can give me some tips/infos on the above.... | | | e.g. stencil aperture design, aperture ratio, common problems and solutions they encountered on the above process, is the profile diff
Electronics Forum | Mon Aug 30 12:02:16 EDT 1999 | Brian Wycoff
| | | | Planning to evaluate the above process... | | | | Can anyone can give me some tips/infos on the above.... | | | | e.g. stencil aperture design, aperture ratio, common problems and solutions they encountered on the above process, is the profil
Electronics Forum | Tue Aug 31 03:37:19 EDT 1999 | Wolfgang Busko
| | | | | Planning to evaluate the above process... | | | | | Can anyone can give me some tips/infos on the above.... | | | | | e.g. stencil aperture design, aperture ratio, common problems and solutions they encountered on the above process, is the
Electronics Forum | Wed Sep 20 19:34:13 EDT 2000 | Dave F
Congrats. You now control the source of almost 70% of the defects of your SMT operation. There is a neat series of presentations on printing, each year at SMI. One of the best of the SMI series was in 1997, because presenters used a common board
Electronics Forum | Thu Jan 04 17:04:43 EST 2007 | slthomas
99% good solder joints = 10000 ppm (defects per million opportunities). Having only built with 0603s I can't speak for a target but that still seems pretty harsh....with a 75/25 0805/0603 ratio at my last place of employment I think we were running