Electronics Forum | Tue Dec 08 17:55:51 EST 1998 | Dave F
1. What is the best way to remove polyurethane conformal coating from selected areas? Your conformal coat material supplier is best equipped to tell you how to remove the coating. Polyurethane conformal coating is not easy to remove. Without in-pu
Electronics Forum | Thu Apr 09 06:22:27 EDT 2009 | qualityguy
We aware of the extend time for cure, and in the CA activity we tried plasma etch and expose the sample to the current process, a screen test of 4 cycles -50C to 125C and the CC held in place. Std IPC tape test passed in current process and modifie
Electronics Forum | Tue Apr 14 17:39:34 EDT 2009 | gregoryyork
Sorry been away for a while. It is actually due to high boiling solvents or plasticizers leaching from the porous resist that kills the cure as it puddles out and has nothing to adhere to. We do have some wipes to check the cure and are looking to ma
Electronics Forum | Mon Aug 22 10:15:30 EDT 2011 | davidalvarez
we have never had a problem using no-clean flux as far as far as shorts and testing problems, using high pressure test probes helps overcome this. The problem we have had is if a unit comes back down the line a couple of years later we notice that t
Electronics Forum | Mon Jun 18 11:17:40 EDT 2001 | Howie
The adhesive type is the problem generally - latex adhesives used are not compatible with the silicone. Humiseal offer silicone compatible tapes & dots although they are quite expensive. I found a 3M product which is compatible with silicone based co
Electronics Forum | Fri Apr 10 07:52:16 EDT 2009 | davef
On cure checking, we have this undated note from Jack Crawford at IPC * IPC-SM-840C "Qualification and Performance of Permanent Solder Mask" has several Test Methods for different types of solder resist material, but probably the only applicable one
Electronics Forum | Mon Feb 06 17:24:26 EST 2017 | westshoredesign
So I had the same question too when I was setting ours up. My lazy (and cheap) solution was: for each program I have a universal path that is used up to the first dispense instruction and after the last one then I covered the surfaces underneath tha
Electronics Forum | Fri May 26 04:58:19 EDT 2023 | auriga2001
I agree with the two other replies. Left alone, it is a defect. If it's just excess adhesive or coating, you can use IPC-7711/7721 'Rework, Modification and Repair of Electronic Assemblies' for guidance on removing. Section 2.3.1 explains how to te
Electronics Forum | Thu May 08 10:16:17 EDT 2003 | davef
Observations are: * Center most lead of the fuse on the top right of the assembly looks like it has excellent solder flow, but this is PTH. From the amount of solder, it must have been wave or hand soldered. * Center most lead of the fuse on the bot
.jpg)
.gif)
