Electronics Forum | Mon Sep 22 04:59:10 EDT 2008 | fadzil66
I have concern about cleaning solder ball after misprinting paste on PCB, currently use vigon 200 with ultrasonic generate but only 70% solder ball able to remove, Any other method or equipment can help to clean solder ball.
Electronics Forum | Fri Sep 26 07:27:29 EDT 2008 | realchunks
This sounds interesting. Could you explain?
Electronics Forum | Mon Jul 04 01:30:24 EDT 2011 | rickysanchez
we encounter bubbles on silicone coating after oven curing.what to do to avoid bubbles?
Electronics Forum | Wed Jul 06 15:52:36 EDT 2011 | duso02
Ricky What silicone coating are you using? Are you using at as a coating or as a potting? In other words how thick are you applying it.
Electronics Forum | Mon Jul 11 11:40:11 EDT 2011 | blnorman
According to the datasheet, this is a LED encapsulant, is that how you are using it? It also had a section on compatibility, which indicates that it is an addition-cure silicone prone to cure inhibition.
Electronics Forum | Tue Sep 23 14:13:29 EDT 2008 | slthomas
In piggy back on Chunks' comments, what you might wipe it with can be the problem. Alcohol absorbed by the solder paste inhibits the effectiveness of some cleaning chemistries, and driving it into the nooks and crannies exacerbates the problem. If
Electronics Forum | Thu Sep 25 17:44:37 EDT 2008 | gregoryyork
strongly agree dont wipe at all, we make an air operated cleaner which blows the powder off while immersed in solvents to break up the flux. cheap and effective as long as you dont wipe first
Electronics Forum | Mon Jul 04 20:10:05 EDT 2011 | rickysanchez
1.The bubbles appear only after the oven curing.before curing no bubbles encounterred. 2.The bubbles were very small, and can be found around the die in between the die and the epoxy. 3.Curing time is 150 degC for 4 hours.
Electronics Forum | Tue Jul 05 16:14:06 EDT 2011 | blnorman
Is this an addition-cure silicone? We once had coating bubbling caused by the evolution of the solvent in the paste flux under leadless components.
Electronics Forum | Tue Jul 05 17:43:43 EDT 2011 | davef
We agree. As Bill says, given that you seem to have bubbles in a restricted area and not broadly dispersed across your board, this seems to indicate an interaction between process materials, rather than a cure or thickness issue.
