Electronics Forum | Wed Aug 18 21:03:41 EDT 1999 | Dave F
| | | | | One of the DFM suggestions I've seen is to remove the solder mask web, i.e. the mask between pads on 20-mil QFP devices. The rational is that if the mask is thicker than the pad the mask can prevent the stencil from making intimate contact
Electronics Forum | Tue Aug 09 11:56:01 EDT 2005 | Rob
We sometimes use a peelable mask the the PCB manufacturer (board house) adds as part of their process. It may seem an expensive option but avoids: Raising P/o's for tape/peelable mask as consumables booking & inspection Booking out to the shop floo
Electronics Forum | Thu Nov 04 10:29:10 EDT 2010 | 18424
Hello all, Has anyone used Kester 2331-ZX water soluble flux on selective soldering and expirienced a white film after soldering. I have seen this on and off for a few weeks now and believe it is a chemical reaction with the solder mask or improperly
Electronics Forum | Sat Feb 20 09:56:22 EST 1999 | Tufty
| We are in the process of getting into no-clean paste and fluxes. One important issue in this is sodler balling. I have heard some people say that having a matte finish would help in having lesser solder balls and that the solder balls would not b
Electronics Forum | Thu May 28 15:54:45 EDT 2009 | elmerito
Hello, We have designed a 160ball bga substrate. Now we want to use the same substrate for the 145ball version of the product. All are the same, the package size, ball pitch, solder ball size only the number of balls will change. We will use a new s
Electronics Forum | Thu Aug 18 13:11:39 EDT 2005 | jsloot
We have our board house apply a peel coat mask that can be brushed off after wave or reflow. You need to brush off while it's still warm.
Electronics Forum | Mon Jan 18 20:51:29 EST 1999 | Dave F
| Can anyone recommend ways of reducing damage to solder masks ... a new wick perhaps. I find that using standard wicks the imposed damage is un-acceptable. | | Also any good links on the subject of bga rework would be really appreciated | | in ear
Electronics Forum | Wed Aug 10 11:57:16 EDT 2005 | pr
Is the peelable mask (put on by the boardhouse) flat on the surface of the pcb? If so can you tell me the material name, so maybe I can find a picture? We have to print adhesive on the board, so the mask has to be flat. That is why Kapton from the b
Electronics Forum | Fri Oct 18 00:44:56 EDT 2019 | Aqueous Technologies
I know you mentioned you use a Tech Spray product. We have had success with their "Wondermask" water soluble product. When using a chemical additive (saponifier) in an aqueous cleaning system we have not experienced residues. I hope that helps. https
Electronics Forum | Tue Nov 09 20:52:34 EST 2010 | ppcbs
Yes, we have had this happen with certain solder masks over the years. Hot air gun is the best solution we can find if the oven doesn't do it. Back in the day when we had a vapor degreasor, freon based solvents would also remove the clouding. Let
