Electronics Forum | Fri Apr 13 10:13:30 EDT 2007 | Bob R.
We had a crisis with one BGA causing huge yield losses due to this defect. Nothing we could do with the profile got rid of it. Changing paste didn't get rid of it. It was the BGA warping in reflow, caused the corners to lift up when the solder was
Electronics Forum | Thu Nov 15 08:25:08 EST 2007 | rgduval
I do think that the designer goofed, and used too large vias. I believe he only used on size via on the entire board, regardless of whether it was in a pad, or out on the board. I have seen vias in pad work, though. From a manufacturing standpoint
Electronics Forum | Mon Dec 17 08:58:21 EST 2007 | Frank
You can spend a couple grand on a manual screen printer, or do what I did back in the day: place the board on the work bench and lay the stencil on the board. If you can hold it steady enough you can use a putty knife to apply your paste. For the s
Electronics Forum | Mon Dec 17 16:04:24 EST 2007 | ck_the_flip
Another tactic. Become friends with all the local solder paste reps, get them to buy you lunch, etc...but the key is...get them to give you free samples. That way you wouldn't have to BUY any paste. As for the original fella, sounds like he's on a
Electronics Forum | Fri Dec 28 17:44:41 EST 2007 | flipit
Back in the mid 90s I used an SVS 3D solder paste inspection system. We used it as a stand along unit but it was an inline model. We would bring printed PCBs off the Dek 265 solder printers and check every 5 or 10 printed panels. They almost alway
Electronics Forum | Wed Feb 20 10:04:15 EST 2008 | slthomas
Yeah, it blows, but basically we toss it when it quits printing. We've never seen any visible quality issues we could attribute to recycling paste like this so we keep doing it. When we start doing BGA and X-raying stuff we'll take a closer look at w
Electronics Forum | Sat Mar 14 09:12:59 EDT 2009 | davef
First, there is no good justification for getting solder on gold fingers. Second, it is well known that solder on gold fingers is unacceptable. So, shipping boards with that condition indicates sloppy quality practices at your CM. Third, that being
Electronics Forum | Sun Nov 22 13:58:45 EST 2009 | tpappano
I didn't attempt to get any written guarantee, but took a leap of faith based on our various communications. The broker was also a refurb operation so I figured we could resolve any technical problems without too much trouble. At this time I'm also
Electronics Forum | Tue Jun 07 08:31:57 EDT 2011 | bootstrap
I am building a rugged digital video camera product that essentially is just a sandwitch of 3 parts: #1: front piece is machined aluminum with C-mount thread #2: middle piece is 1/16" printed circuit board #3: back piece is machined aluminum The
Electronics Forum | Fri Dec 16 10:13:33 EST 2011 | rapid
About the automated printing machines: They are all a little different, but the alignment part of the process is basically the same. I don't know if you have ever seen an automatic printer, so I'll do my best to explain it. The PCB rides into the
