Electronics Forum | Tue Aug 21 21:39:19 EDT 2001 | davef
1) why is No-clean (NC) the preferred process, for BGA mounting by SMT? Probably the same reason NC is the preferred process for mounting non-area array SMT components. 2) why is water-soluble (WS) not a hot choice? There�s not reason not to use
Electronics Forum | Wed Jun 06 21:19:41 EDT 2001 | davef
Consider running two sets of stencils and washing every four hours.
Electronics Forum | Fri Mar 14 11:18:29 EDT 2008 | operator
The way it works is the liquid solder immediatley cures (or should I say burns) the WSOL where ever it touches it. This hardens and keeps it in place and protects whatever is under it. Some of the WSOL falls of in the pot. I am suprised that the burn
Electronics Forum | Mon Feb 19 11:36:39 EST 2001 | billschreiber
Hello Mark, I wish it were that simple so I could direct you to a particular manufacturer and stencil cleaner model. Unfortunately, there are several issues complicating the process of cleaning all these applications in one machine. First and fore
Electronics Forum | Mon Dec 29 09:10:22 EST 2008 | stepheniii
It takes time for the moisture to penetrate into the body. I think the 5 years of ambient would be more the culprit than washing the boards. Especially since you are baking them after wash. Get a few of the ICs and put them loose on a board and put
Electronics Forum | Tue Jun 05 20:45:54 EDT 2001 | davef
So, yer lookin' to detect a ~25um glob on the wall of the aperture on yer stencil, eh? Why not wash your stencils before you put them away? That's what we do. Give 'em a quick looksee, then rack 'em, if they're clean. Give 'em anudda looksee befo
Electronics Forum | Thu Feb 10 09:01:40 EST 2005 | russ
I have done that also, It does work well. One issue we had was that the mask didn't come right off during the first wash cycle since it was put on much heavier than the mfgr suggested (.01"). We had to soak them in some water first to soften it up
Electronics Forum | Tue Jan 06 14:37:27 EST 2009 | stevek
The easiest way to prove out the absorbtion theory is to weigh the parts before wash, after wash, and after baking. You probably want to do this with the bare parts in isolation as the fab will pick up considerable moisture. Differences in weight s
Electronics Forum | Thu Nov 04 19:51:28 EST 1999 | John
Thanks folks. The current vendor is doing an alcohol wash, top and bottom, then performing an ionic test on 100 boards. I'm not to confident in the testing because the readings for a "clean" board are 25 ugm/sq in and a "dirty" board are 40 ugm/sq in
Electronics Forum | Wed Feb 09 21:19:03 EST 2005 | Mrduckmann2000
Russ, We can not use a wave pallet, already went that route. We have parts next to the thru-hole pins and between thru-hole pins. I am going to try an experiment in the next day or so with solder mask. I plan to solder SMT parts on the back of se
