Electronics Forum | Wed Apr 30 07:33:12 EDT 2008 | davef
It's not acceptable to us. More importantly, you need to determine if it's acceptable to your customer. Recognize that your little IPA scrub does NOT remove the OA flux residues from the board. It mearly spreads them out across the board and under c
Electronics Forum | Tue Jun 24 12:42:35 EDT 2008 | slthomas
Your flux residues may be acceptable for your drain, but the solder balls won't be. You'll need to filter and dispose of the filters per your local city, county, and state regs. Either that or just boil the water off and dispose of the dry remains wi
Electronics Forum | Wed Aug 27 18:28:29 EDT 2008 | blnorman
We have an immersion silver board that has a brown discoloration after processing. It's not flux residue, that normally doesn't cause this condition. Elemental analysis shows less than 1% sulfur, and I thought silver sulfide is more a black color.
Electronics Forum | Sun Nov 22 19:59:26 EST 2009 | prodivegsr
Hi Davef, The bubbles occurs at the body also...there's also a washing process before the conformal coating:-the Flux residue are removed after washing. ... The curing profile is also something that we are looking into during the initial troubles
Electronics Forum | Fri Nov 20 14:50:13 EST 2009 | davef
One of our instruments has a high impedance front-end. We: * Passed functional test in the environmentally controlled shop. * Failed test, on the same unit, while carrying it to burn-in chambers in an uncontrolled part of the plant. Solder flux resi
Electronics Forum | Sat Nov 21 01:42:28 EST 2009 | Sean
Hi Patric, You are right...WE found that this problem disappear once we seal the PCBA bottom side (Intel's Northbridge area). Once we remove the seal, the problem is coming back.. In this case, I thnk conformal coating is necessary... Besides, I
Electronics Forum | Thu Jun 28 16:02:05 EDT 2012 | allwave
We had a similar problem with foam in our inline cleaner (TD). The problem were the solder paste flux residues. Boards went straight from SMT to Wave process and then washed. Anyway we changed the solder paste and problem solved. Are you using saponi
Electronics Forum | Tue Jan 30 10:44:02 EST 2018 | emeto
If you go even further, the flux residue actually isolates the joints from the surrounding atmosphere, so it is actually supposed to be there. Adding a step in your process that is obsolete, doesn't comply very good with the whole lean concept. I don
Electronics Forum | Thu Feb 01 15:36:42 EST 2018 | davef
Not to be repetitious, I just don't remember if this has been said or not, I'm old, give me a break. Some people have found that DI water is too thick to properly remove flux residue under low stand-off components.
Electronics Forum | Mon May 26 09:31:41 EDT 2008 | davef
What steps are taken in low residue wave soldering to assure the proper amount of flux is applied prior to soldering? * Too little flux can result in poor solder flow. * Too much flux can result in corrosive residues left on the board after soldering
