Electronics Forum | Tue Sep 15 12:11:36 EDT 1998 | Bill Schreiber
Jeff, The use of flux thinner would only add another chemical to the process. Environmentally, that would not be a good idea. My guess is that you would only end up with "thinner jelly" anyway. Alcohol works well on RMA flux. When assemblers switch f
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 | Mon Mar 27 21:09:29 EST 2006 | ms
Thanks Dave I'm not convinced the air is necessarily in the paste from manufacture - suspicious that it may be folding in during the change in direction of the print cycle - or as the paste travels across apertures. It is not necessarily in the fir
Electronics Forum | Wed Feb 11 00:34:42 EST 2015 | comatose
There isn't going to be much worthwhile used equipment out there if you mean true jetting - it is a pretty recent process. There are lots of used stencil printers out there, so from an up-front cost perspective, stencil wins. Jetting is slow. A hig
Electronics Forum | Wed Oct 10 20:35:17 EDT 2001 | djarvis
Stephen, I don't understand this at all mate. 1. If you don't place a QFP and get bridging across the bare pads, you were gonna get absolutely horrendous bridging if you did put one down. That points to poor printer set up or stencil design or both
Electronics Forum | Wed Mar 27 21:20:30 EST 2002 | davef
There is two major BGA coating camps. * Camp #1: "We require the coating to be under low stand-off devices but with no filleting. So we apply a thinned dip coat first, and then top-off with a proper spray coat" * Camp #2: "We want no coating under th
Electronics Forum | Tue Mar 12 22:27:50 EST 2002 | davef
I'd speculate that the properties of a well formed solder connection processed in air and N2 are indistinguishable. Then again, the pitch is that N2 gives a wider process window, especially for NC flux-types. In the SMTnet Library look for: �Opti
Electronics Forum | Fri Aug 07 07:52:15 EDT 1998 | Earl Moon
| | Is there any problem using SMT on gold boards? 15 years ago we were told not to use gold boards, but I can't remember why. Judging by the other postings it now appears to be common. Only problem I see is that the nickel should be plated, not e
Electronics Forum | Thu Aug 26 14:45:09 EDT 1999 | Earl Moon
| What are the key steps to achieving high yield with CSP ??? | | (We are trying qualify vendors for volume fab/assembly of some | products which use several CSP devices on each side of the | board. (Some with 0.5mm ball pitch)) | | Looking throu
Electronics Forum | Sat Feb 10 17:12:03 EST 2001 | rpereira
I admit, 16 mil QFP printing is very challenging but if all your control factors (print speed, etc...) are setup correctly (through DOE) extremely high yields can be achieved and more importantly a repeatable and robust product will be manufactured.
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