Electronics Forum | Fri Jul 10 09:56:11 EDT 1998 | Justin Medernach
| I am looking for some guidelines on evaluating solder paste. I am specifically interested in No-Clean Pastes, as they are a completely new ball game when it comes to slump, tack time, stencil life, tack time, etc. | Thanks for any and all help give
Electronics Forum | Wed Jan 28 19:39:08 EST 1998 | Steve Gregory
| | What is the lifetime for a typical solder paste ? | | How long can boards be stacked waiting before the paste goes off ? | Lifetime and tack time depends on: | - Manufacturer | - Flux/mixture | - Environmental conditions | Typical lifetime is dep
Electronics Forum | Thu Apr 03 22:56:48 EDT 2008 | davef
Potential impacts of using expired solder paste are [University of Bolton]: * Changed paste rheology. Result: poor print quality * Loss of solvents. Result: reduced flux activity * Changed flux formulation. Result: More difficult to clean flux residu
Electronics Forum | Tue Jun 11 14:58:45 EDT 2002 | Chris Lampron
Hello Sean, We are currently using a Pin in Paste process to mount some through hole relays. This particular board has 72 relays per. We have cut the stencil to overprint the hole. By putting a small amount of solder in the hole to flux the lead, th
Electronics Forum | Tue Jan 11 11:14:09 EST 2000 | Wolfgang Busko
What a challenge! I think it all depends on the equipment used. Seems rereflow of BGA isn�t that good (see the advices for wavesoldering BGA populated boards). Although you might check for the tacking force by sending a sample BGA board head over thr
Electronics Forum | Sun Oct 10 00:40:42 EDT 1999 | John
| I'm searching for a source for surface mount socket savers that accept a hand test socket (Yamaichi, Nepenthe etc...). Barring availibity of an SMT socket saver does anyone know a good technique for soldering socket savers into a .250" thick, 20+ l
Electronics Forum | Wed Aug 18 08:38:46 EDT 1999 | Jason Gregory
| Is there process by which one can do a double sided reflow (SMT on both sides) in one pass through the oven? | Paul, Here's a way it might be done. Screen your bottom side with paste (if only passives, 0603-1206 & sot 23's), dispense glue for sam
Electronics Forum | Tue Jun 02 12:58:07 EDT 1998 | Michael Allen
"...the part is aligned to the pads with in 10% before going into the IR oven." Sounds like the pad pitch might be okay (?). If that's not the problem, then what? I wish I had the answer, because I've struggled with heavy QFPs for some time now (2
Electronics Forum | Mon Oct 07 18:03:16 EDT 2002 | russ
David, Guess what, Today I happened to try my new sample of Kester HM531 and I also was blown away by the results! I could not find voids anywhere! (same profile etc...) One thing I noticed during my testing however was that it seemed like after I
Electronics Forum | Thu Dec 12 09:21:42 EST 2002 | blnorman
What we did: *Slump-dot diameter and height as a function of time *Print Speed-Vary speed, measure slump and missing/defects *Green Strength-We quantifiably measured tack vs time and we placed components and measure skew by SVS *Cure profile sensitiv
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