Electronics Forum | Thu Jan 03 08:02:53 EST 2002 | davef
Slump is a function of the particular paste you select and the temperature of the paste. Use a slump test like the one that follows to compare fluxes. Slump Test Step Process activity 1 Print paste on white ceramic substrate or microscope sli
Electronics Forum | Thu Jul 07 18:07:38 EDT 2005 | saragorcos
Ahh. sorry for the foul up - and thanks for stopping the spread of misinformation!! Sarag
Electronics Forum | Tue Nov 04 07:50:14 EST 2008 | davef
Sure. Here's what you should do to apply repeatable amounts of flux on BGA during rework: * Squirt some gel flux on a plate or something like that that has a flat bottom and raised sides to corral the flux. * Cut notches into one edge of an old credi
Electronics Forum | Mon Nov 12 18:08:37 EST 2007 | samir
That's when you give that "Supervisor" a tall glass of SHUT THE F*CK UP. I betcha you regret even mentioning it to him. I'd have just made up some techno-babble and switched it regardless. Told him something like - "pure IPA will act as a catlyst
Electronics Forum | Fri Jan 28 12:29:01 EST 2005 | Bob R.
We use the exact same method Chunks outlined for evaluating just about anything we're going to roll out worldwide, whether it's a material or a machine. List your factors (print speed, solder spread, etc), assign each a weight, evaluate each paste a
Electronics Forum | Fri Jan 28 12:18:32 EST 2005 | Chunks
Your best bet is to do a decision making matrix. Each company has so many different criteria�s it's hard to pick out which one might be important to yours. Simply pick out your top 5 paste manufactures. Next decide what your "Eliminators" are - th
Electronics Forum | Mon Jul 10 07:46:51 EDT 2006 | ronalds
You are right, RSS profile is not the correct description. I am using a profile which heats up quickly to let the flux spread. Next linear up to activate the flux and prevent thermoshock. My experience is however, that small changes in this profile
Electronics Forum | Fri Jan 24 16:54:24 EST 2014 | davef
Yeh, I worked at Wang Computer factory in a reclaimed fabric mill with wooden floors. One of the causes of grapping is flux loss. In their paper, Briggs and Laskey talk about flux loss due to spreading and suggest: * Graping is much less prevalent i
Electronics Forum | Wed Apr 18 01:07:25 EDT 2001 | MW
I some something like this. My package was not flat the belly of the body rested on the PCB. We found that every 4-5 part would wander to the side. What was puzzling is that the blowers would have blown it the opposite side. ultumately we proved
Electronics Forum | Tue Sep 28 17:56:02 EDT 2004 | Vee Sar
Adam, I would first check hole to lead sizes on the components that you are having hole fill issues with to see that the spacing is withing spec. Second, check for oxides on lead tips, and contaminated leads that cause poor wetting and insufficient
