Electronics Forum | Mon Jul 17 11:19:46 EDT 2006 | Chunks
Never seen a direct study on these two correlation�s before. But if you have moisture sensitive devices, higher humidity could have some affect on them. If you are talking regular Rs and Cs over wave solder - I kinda doubt it. Water based fluxes d
Electronics Forum | Wed Sep 20 16:27:06 EDT 2006 | proy
As we are a low volume shop, the extra handling is not too much of a concern. My biggest concern is if the flux sitting on teh board for a long time (few hours) is going to cause any problems in solderability. My thought is that it should not as it
Electronics Forum | Mon Nov 06 10:03:19 EST 2006 | SWAG
I don't know of any articles but you will see the following problems: The flux will evaporate from the paste and your solder joint will look very grainy or will not reflow at all. The paste will not have a good, tacky quality. Your pick and place
Electronics Forum | Tue Jun 26 21:41:10 EDT 2007 | davef
4.4 Determine the amount of flux on the board. 4.4.1 Get a piece of corrugated cardboard and a weighing scale accurate to 0.01 grams. NOTE: Use cardboard with alcohol fluxes to slow their evaporation and get good data. 4.4.2 Weigh the cardboard. 4.4
Electronics Forum | Mon Dec 17 12:11:29 EST 2007 | chef
Whoa dude - slow down- maybe great beer money but if you don't have good environmental and ESD controls in your shed, all your suds slush fund will evaporate in RMA's costs. A small pick and place (table top) would do. A manual screen printer would h
Electronics Forum | Thu Feb 28 14:04:39 EST 2008 | tonyamenson
What happens as solder paste is used when it becomes un-usable? Does it dry out due to flux evaporation or does it absorb to much moisture from the air which changes its composition too much? Now for the big question. I had an operator add flux to t
Electronics Forum | Tue Dec 16 16:49:22 EST 2008 | scottd3
We ran into this problem before, on all of our models. We never quite found out the reason, we do know that if the PCB is passed through a reflow oven that is extremely dirty with evaporated solder paste flux, it will make it extremely difficult (or
Electronics Forum | Mon Nov 16 10:50:50 EST 2009 | ppcbs
I agree customer is being overly stringent, and that their is a possibility that BGA's have voids prior to installation. If you determine that the BGA's do not have voids prior to installation I suggest you slow down your ramp speed to allow the flu
Electronics Forum | Tue Nov 24 05:23:18 EST 2009 | prodivegsr
Hi Davef, Thanks...Saw 1 of your thread that you posted : Thanks for providing... From davef : There are many possibilities: * Conformal coat is incompatible with surface residue on the board * Conformal coat is incompatible with solder mask on the
Electronics Forum | Mon Jan 11 09:15:36 EST 2010 | lynn_norman
In a former job we had issues with leakage currents on a QFP. The component was acting as a thermal shield leaving a lot of flux residue behind. To make it worse, the flux solvent wasn't totally evaporated, so we had ionic residue, a fluid media, a
