Electronics Forum | Thu Oct 26 08:59:56 EDT 2000 | Antonio A. Medina
Ok guys, I need help. Here's the deal. We're getting micro solder balls under discreets on the bottomside of the board. Here's my set up... MPM screener w/vacuum plate 6 mil metal screen with 90% circular (rounded) apertures 7 mil (measured) past
Electronics Forum | Tue Oct 19 19:25:40 EDT 1999 | Jeff Sanchez
Carol, I think the guys are right about you stand off problem but I want to address the wrinkleing of your masking. Although I think the temps you are subjecting the board to are very high and more than likely creating problems of their own. I th
Electronics Forum | Fri Oct 30 08:22:57 EST 1998 | Michael Nguyen
I finally got my problem figured out on the bridging, the only thing I'm finding is that I notice some litlte solder balls on the bottom of the board. Is that normal? Is that why I'm getting bridges? Has anyone came across this problem and pass the i
Electronics Forum | Sat Sep 21 23:38:06 EDT 2002 | ivanchu
I got one problem from my production line recently. One 0.5mm pitch QFP IC have been used on my PCBA. Actually, the defect was happened in randomly. Sometime, we got the fillet completely but sometime is not. The solder joint look like is good, but t
Electronics Forum | Thu Apr 06 08:31:13 EDT 2000 | D Scott
Angela Do you see this problem on other .5mm pitch devices or is it only on the QFP? Check placement height, too low or to high can cause you problems Pad co-planarity, are your boards HASL? Is your board sagging during placement(board supports) An
Electronics Forum | Tue Oct 11 14:02:59 EDT 2016 | mnorthey
We have a slider Bar on the back side of our Delta Wave. It is adjustable and slides up and down (adjusting bolt) on the back edge of the Lamda Wave to prevent this problem; keeping the trough behind the Lamda is essential as well. Along with attenti
Electronics Forum | Thu Oct 29 21:16:15 EDT 2009 | mah115
Fellows, We are considering getting an AOI machine to inspect boards that our vendors are giving us (we outsource the assembly of PCBAs). We have low volumes of boards, but every time a defect does slip by our human inspectors, it causes a lot of
Electronics Forum | Wed Jun 17 16:19:10 EDT 1998 | Ryan Jennens
| We are facing a problem of high contamination on boards after wave soldering. We want the contamination to be under 24 ugm/inch square. We are using a no clean flux with the spray fluxer unit of wave soldering. The contamination is higher on the e
Electronics Forum | Tue Feb 19 19:36:21 EST 2002 | davef
You weren�t clear but I assume the problem is not widely distributed and affects only a few parts on each board. Do this trick: * Cut a ~1� piece of fairly serious wire, like 18 or 12 AWG. * Strip the insulation. * Gear-up with gloves, glasses, and
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
