Electronics Forum | Tue Feb 19 14:00:55 EST 2002 | global
We have had some discussions about what causes parts to lift out of the holes when going over the wave on our flow solder machine. The machine being used is a Treiber (700 series). There are two bottom pre-heaters and one top pre-heater. We try to pr
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 | Wed Feb 21 08:06:23 EST 2007 | davef
The cause could be a lot of different things. As long as you didn't use excessive reflow temperatures, we'd guess that: * Solder mask blister: Your board fabricator should be able to demonstrate through TMA [or equivalent] analysis that the mask wa
Electronics Forum | Mon Oct 31 08:29:51 EST 2005 | chunks
Shifting? Please describe the "Shifting". I.E. is it centering, sliding to cause shorts..... Most 208s will self center. If it's causing shorts, first check your print to make sure it is on the pads. Next check placement. Another area to check
Electronics Forum | Thu Jun 08 01:46:00 EDT 2023 | camilleyang3
To prevent BGA (Ball Grid Array) issues related to SMT (Surface Mount Technology) solder resist when fabricating a PCBA (Printed Circuit Board Assembly), you can follow these guidelines: Design considerations: Ensure proper spacing between BGA pads
Electronics Forum | Wed Nov 17 11:20:23 EST 1999 | Dave F
Hey Gyver: If you don�t mind (which you don�t have any choice about, because I�m going to do it anyhow, cause it�s MY word processor), I�m going to respond genericly, but still be directed to your question. Much of the following is paraphrased from
Electronics Forum | Sat May 02 08:48:32 EDT 2009 | davef
You have a board defect. Any moisture and/or organic contaminants trapped by the solder resist during lamination may cause solder mask delamination, blistering and/or adhesion loss during subsequent soldering operations or during extended use.
Electronics Forum | Wed Jul 23 08:18:29 EDT 2008 | davef
Q1. Is this a standard process for plugging? A1. Not as such. We checked both IPC-6012 and IPC-SM-840. Neither comments on plugging. So, your fabrication notes rule the day. Q2. Is this okay for such thick PCB's or is it mandatory to use a special pl
Electronics Forum | Sat May 09 23:05:17 EDT 2009 | kareal
Davef, It seems the tin resist residue on copper trace is root cause of whitish layer. but it could explian why I could not detect tin on fresh unit without UHAST. I have performed X-section and EDS analysis on many fresh units,but no any tin was
Electronics Forum | Thu Jul 01 20:47:48 EDT 1999 | Scott McKee
I called a new customer today and told him that one of his parts on the proto boards (a capacitor with a polarity 'tit') was too long for the pads and the pads were small causing the end opposite of the "tit" to lift up. I suggested that the product