Electronics Forum | Tue Nov 06 07:34:26 EST 2007 | scottp
I'm not sure what kind of marginal joint you're trying to identify, but when we went through a serious ball-in-cup problem a few years ago we tried hot & cold functional test as well as a day or two of -40/+125C thermal cycling and all were pretty po
Electronics Forum | Tue Sep 04 07:34:02 EDT 2001 | Shvetang Dewashrayee
We have problems of solder shorts while using DEK Infinity printers. Some of the manufacturing lines are configured ina way that the side (bottomside) of PCBs mostly with passive parts is screened first and then the otherside (topside) of the PCBs w
Electronics Forum | Tue May 23 10:40:25 EDT 2006 | Chunks
Chris is right. You can do a good visual after placement if you have outline marks on your silk screen. That helps a lot. What size BGAs are you talking about. That would determine how critical you want to get with inspection.
Electronics Forum | Tue Jun 02 07:31:55 EDT 2009 | scottp
Early on when we started looking at BGAs we tried dipping. We've done it in production for a couple decades with flipchips. Dip fluxing BGAs worked fine in the lab but we ended up starting production with screen printed flux for cycle time reasons.
Electronics Forum | Thu Aug 24 12:09:35 EDT 2006 | Chunks
Now how did you know we were wave soldering BGAs onto a board that goes into a karaoke machine? Thanks for everyone's input. We currently use tacky flux, but I beleieve we will also look into screening paste onto the BGA as well.
Electronics Forum | Tue Aug 26 14:13:46 EDT 2003 | robd
We have seen "coplanar problems" on BGAs supplied by some suppliers. We have seen large enough spere variation to cause opens with our standard .006" paste process (paste and profile work fine "most" of the time) . Although not an extremely technic
Electronics Forum | Mon Jun 07 14:13:53 EDT 2004 | ricardof
Gabriele, yes you're right, but my question is more focused to restrictions as for the Operators, and then the performance in Screen Printer and Oven. The board has 400 high speed parts and 20 parts for Odd Shape machine (QFPs and 2 BGAs), Board is n
Electronics Forum | Mon Oct 09 09:02:06 EDT 2017 | smtpatrick
I have used Mycronic MY500 & MY600 printers in the past. Wave goodbye to screens, it's really quick & easy to modify print programs, changes can be made and applied in 5 minutes instead of waiting 24 hours for a new screen. They print slower than a
Electronics Forum | Mon Oct 09 09:16:45 EDT 2017 | vchauhan
I have used Mycronic MY500 & MY600 printers in > the past. Wave goodbye to screens, it's > really quick & easy to modify print programs, > changes can be made and applied in 5 minutes > instead of waiting 24 hours for a new > screen. They prin
Electronics Forum | Tue Sep 20 17:09:14 EDT 2005 | hly
I have a situation with hot boards with fine pitch BGAs that I need to build. However, there is a big problem--the auto screen printer is down. I decided that we would use the stencil and manually line up the pads and do a manual print. I can't ac
