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 | Thu Dec 12 09:21:42 EST 2002 | blnorman
What we did: *Slump-dot diameter and height as a function of time *Print Speed-Vary speed, measure slump and missing/defects *Green Strength-We quantifiably measured tack vs time and we placed components and measure skew by SVS *Cure profile sensitiv
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 | Fri Jul 06 03:23:01 EDT 2001 | kennyhktan
Hi there Steven ! Please allow me to share some of my problem we're facing here with you. Here are a few points that I suggest you should check on your current process:- (1)PCB - Component land partern design ? It is per IPC spec ? - Mask
Electronics Forum | Mon Oct 14 17:59:45 EDT 2002 | russ
When I used the micro-stencils, We purchased the holder from the stencil manufacturer. As far as design we used 5mil stencils for uBGAs,6-7 mil for larger 63/37 balls, and 8 mil for CBGAs. Aperture openings used were slightly smaller than what we wo
Electronics Forum | Wed Sep 30 06:22:23 EDT 2015 | mervin
MPMENG, Thank you so much for taking the time to help. The machine has Y snuggers and flippers. The Pcb is loading in the center all the time. The driver cards look fine there is no obvious faults on them or partially burned. The machine was not in
Electronics Forum | Tue Sep 19 22:15:53 EDT 2000 | Sophia
Hi guys, I have been working in the SMT pick and place process for five years, and now I'm responsible for the solder paste printing process, and one thing that I notice is that the actual process that we have is to poor, actually our main defects a
Electronics Forum | Thu Aug 31 00:07:24 EDT 2000 | Ramon I Garcia C
I Kyung: I'm not sure if we are working with PIHR but we insert some pines in a PCB with a pin inserter machine, after that we run this pcb in a screen printer and put over its solder paste, and then run in a chip shooter and then IC placer and f
Electronics Forum | Tue Jun 27 10:51:42 EDT 2000 | Ioan
Hi Bill, there are a couple of things you should check. Most likely you have too much paste which is squashed at the insertion of the cap. - the paste height, around 7 mils should do. Too much paste will cause shorts under the cap at insertion which
Electronics Forum | Thu Apr 06 00:27:42 EDT 2000 | Dean
I would check their data sheet for the particular product. Thats the range I have for Some Kester products I use... Are you seeing any slumping prior to pick-and-place? Is the bridge in the same place every time? How is your pick-and-place mounting
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