Electronics Forum | Wed Oct 01 21:22:37 EDT 2003 | ramanandkini
We have a 1.6 mm thick automotive PCB board of size 35x70mm. One of our vendor has given us a batch with lesser soldermask thickness 5~8 microns. Will this affect the circuit board on a long term. What should be standard for the soldermask thickness?
Electronics Forum | Fri Oct 03 07:49:18 EDT 2003 | mk
Mask Musings. Soldermask (SM) and its functions have changed and evolved over the years. As an ex-solder mask applicator, I can remember screening Colonial High Gloss Epoxy soldermask on boards back in the early 80's, ending up with a thickness that
Electronics Forum | Thu May 20 14:32:06 EDT 2010 | davef
First, what's wrong with some dewetting of conformal coating on component bodies? Second, there are chemistries that might be able to remove silicone mold release, but cleaning the chemistry is not easy without affecting the whole board, as you impl
Electronics Forum | Wed May 19 19:46:41 EDT 2010 | jry74
I am experiencing sporatic de-wettting issues, so I have been thinking about ways to clean fully assembled circuit boards that have open switches, contacts, etc. I also suspect that that plastic bodied components have residual silicone mold release
Electronics Forum | Thu May 20 07:52:36 EDT 2010 | rgduval
In general, cleaning with deionized water is acceptable for most component. Open switches and contacts, in general, do not get damaged in this process. A good drying is required, of course, after washing. However, you've described dewetting issues
Electronics Forum | Thu May 20 08:51:29 EDT 2010 | jry74
A lot of our dewetting is happening on plastic body components, such as ICs. When they are manufactured, the molding process requires a mold release to make the part release after molding. Usually, the release agent is silicon based, but you can't
Electronics Forum | Tue Dec 07 13:40:25 EST 1999 | Tim
The company I represent provides electronic manufacturing services. Some of my customers ask that we ship their boards "un-tested". By un-tested I mean we build them, visually inspect them and out they go. I find that on un-tested boards, it's not
Electronics Forum | Wed Aug 09 08:06:07 EDT 2006 | davef
See "IPC-4554 Specification for Immersion Tin Plating for Printed Circuit Boards" 3.2.1 Immersion Tin Thickness. The most common reason for solderability issues with the white tin surface coating during multiple thermal excursions is a thin white ti
Electronics Forum | Tue Dec 07 14:21:41 EST 1999 | Brian W.
In my experience, the most commonly accepted theory is that 100% inspection is only 80% effective AT BEST. That means that if your inspoectors are happy, noy outside concerns, well-rested, etc, they will catch 80% of the defects. This number goes d
Electronics Forum | Wed Dec 08 02:07:25 EST 1999 | Scott Cook
Tim, What Brian writes is all true. However, let em put it into a sales / marketing perspective..... The REAL issue in your situation is: Who is responsible for the failures which WILL result in shipping untested product? Typically, your customer
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