Electronics Forum | Fri Jun 29 14:13:05 EDT 2001 | markhoch
Just a quick thought on solder balls "or beads" caused when using NC paste. I found a spec (12.4.10 in IPC-A-610C) that says solder beads are acceptable if they are entrapped in NC flux residue and can not be dislodged in the normal service environme
Electronics Forum | Sat Jun 23 21:04:44 EDT 2001 | Stefan
If you want to tinker a bit with old machines, you could buy an inexpensive ( under $ 10,000 ) used Pick&Place machine and reverse the polarity on the tape feeding motor. If you don't heat seal the cover tape, but use pressure sensitive cover tape,
Electronics Forum | Sun Jun 24 05:03:20 EDT 2001 | ronih
Hello, I need some information about footprint of BGA / fine BGA. As far as I know the pad on PCB should be the same as the pad on the BGA (much smaller than the ball dia.). I need some information regarding the hole SMT process: - Paste printing:
Electronics Forum | Mon Jun 25 17:01:18 EDT 2001 | traviss
Do you by chance have a copper layer soaking the heat away from the pads? If you do or even if you don�t you may want to try bumping your bottom heaters up, try bringing the heat through the PCB. This may help pull the solder down to the pads. This m
Electronics Forum | Tue Jun 26 07:40:18 EDT 2001 | caldon
Try this link out. http://www.airliquide.com/us/ep&a/TechPapers.htm Air Liquide has done many studies on this topic. There should be some useful information there. Cal Caldon W. Driscoll ACI USA 610-362-1200 cdriscoll@aciusa.org
Electronics Forum | Wed Jun 27 13:55:10 EDT 2001 | peterson
We are having some difficulty achieving 75% fill on some through-hole power connectors. The board is very thick. Any suggestions? Our plan is to preheat extensively, pre-tin the leads and perhaps add paste in hole. Anything else that might achieve th
Electronics Forum | Fri Jun 29 13:13:32 EDT 2001 | Brian W.
What workmanship standard are you working to? The IPC book has an allowance for boards with heatsinks or thermal masses that allow less than 75% barrel fill on through hole parts. I would suggest that you check your board layers and determine if yo
Electronics Forum | Wed Jun 27 15:21:28 EDT 2001 | H.Richter
Hello; Can anyone give me advise on the best way to manually align a 20"x20" stencil on a semi-automatic printer? We have a board with a 16 mil pitch QFP and have difficulty aligning the stencil. We have tried various alignment schemes on the pcb an
Electronics Forum | Wed Jul 04 15:13:17 EDT 2001 | davef
Dunno, but our a/c cats asked us the same question a cuppla of years ago and we couldn't figure-out what they were talking about. So to not get wrapped around the axial, we defined our heat sources in terms of time, temperature, durations, etc. Thr
Electronics Forum | Wed Jul 04 02:04:22 EDT 2001 | Mike
Hi Dave, Thank you for your information. How about the glue print on PCB and not mount component, what is the idae to inspection this glue is suitable for mounting component. For example insufficient glue excessive glue. Because we found the problem
