Electronics Forum | Fri Feb 20 14:33:47 EST 1998 | Dave McFadyen
Looks like (so far) we have a concensus. Follow the paste manufacturers guidelines on storage. Normally, refrigeration is required to achieve max shelf life between 3 and 6 months in original closed container. Water-wash pastes are much more active t
Electronics Forum | Wed Feb 05 13:08:20 EST 2003 | joeherz
You're correct that a thicker solder deposit will make bridging on fine pitch devices a bigger risk. Another alternative could be to slightly over-print the pads (onto the soldermask) ala pin-in-paste process. Basically adding enough solder to fill
Electronics Forum | Sat Apr 26 20:27:18 EDT 2003 | LWEI
I'm working on a protobuild for a pcba. THis pcba uses double-reflow, paste-in-hole process. On bottom side there is a Ceramic BGA, size 35 X 35 mm, thickness 6mm, over 900 balls count (ball pitch 1mm)and it weighs a hefty 20 grams. Printing uses 6 m
Electronics Forum | Fri Jul 04 09:10:53 EDT 2003 | davef
With poorly cured mask: * Wave soldering: Expect to see thin wavy band of dross imbedded in the mask in the wave solder side. * Reflow soldering: Expect to see a pinto board where the two tones of mask are [1] normal color and [2] a lighter color, al
Electronics Forum | Tue Sep 06 09:20:50 EDT 2005 | Bob R.
We approached it the same way we select SnPb pastes. We started by doing coupon level tests to sort out the obvious "bad" pastes: SIR, wetting, solder balling, print quality, etc. That cut the field in half. From there we started to do assembly l
Electronics Forum | Mon Aug 21 04:20:49 EDT 2006 | Rob
Hi Mika, I used to work for the largest chip cap manufacturer in the world, and by far the largest problem we would see was cracking due to incorrect z height adjustment on Chipshooters. It can also cause solderballs and bad joints by displacing th
Electronics Forum | Mon Aug 30 06:47:18 EDT 2010 | arjan
We having issues installing the Linear Tech LTM8023. We have different soldering results in our PBfree testruns. The voiding and solderball rate is not stable (random positions and sizes). The pcb's (gold finish)are prebaked, the LGA's are stored in
Electronics Forum | Tue Mar 23 23:17:03 EST 1999 | Chris G.
| Are there many of you who are soldering through hole parts in your surface mount reflow oven? How repeatable is the process? Do you need to touch up a lot after reflow? We don't do long runs maybe 200, 300 boards max. Can you just screen print
Electronics Forum | Mon Apr 17 18:42:32 EDT 2000 | Russ
Murad, I have just completed a switch over in our facility to no-clean. We used Alpha 609 and 857 paste and wave flux respectively. We currently use Alpha UP78 paste, NR330 wave flux, NR205 liquid flux for touchup and cleanline 7000 wire solder as
Electronics Forum | Tue Oct 19 14:56:55 EDT 1999 | JohnW
Nick, I've run this flux for a while and it's not too bad. There is a tendancy for there to be residue left on the PCB after wave due to the solid's content but it can be minised by putting some effort into setting up your spray fluxer to an optimum
