Electronics Forum | Thu Jan 25 21:49:12 EST 2007 | realchunks
Wagoner, Try switching to a transitional paste designed for no lead parts on a leaded board. Running your current paste at higher temps will dry out your flux too soon, which may be your problem.
Electronics Forum | Tue Jan 30 04:20:26 EST 2007 | Phil J
Print your paste onto a ceramic tile, place the offending component onto it and send through the reflow oven; then observe the results. You will soon see if the component is solderable!
Electronics Forum | Thu Jan 25 12:18:40 EST 2007 | wagoner
There are several smd components in our factory that don't reliably wet to solder during reflow. Paste and placement are good, but the component won't wet reliably. All of the other components on the boards solder fine, but one of these components
Electronics Forum | Fri Apr 04 01:39:21 EDT 2008 | slthomas
All of what Dave says is spot on. I suspect that the most likely corresponding defects on your assemblies would be poor wetting and insufficient solder.
Electronics Forum | Fri Apr 04 08:49:45 EDT 2008 | ck_the_flip
Define "expired" though... 1 week? 6 weeks? 1 month? 6 months? Unrefrigerated life is generally 30 days. If paste has been stored refrigerated at manufacturer recommended temperatures, what would you guys do, like say, if you owned your own shop
Electronics Forum | Thu Feb 17 21:42:12 EST 2000 | Dave F
Hey Bud: Moved from that Bi-crap to something serious, eh? Several things: 1 Get in touch with Doug Romm (drom@msg.ti.com) at Texas Instruments. He talks palladium. 2 Review the archives on Palladium. 3 I think you're running light on temps. Eut
Electronics Forum | Thu Feb 17 21:42:12 EST 2000 | Dave F
Hey Bud: Moved from that Bi-crap to something serious, eh? Several things: 1 Get in touch with Doug Romm (drom@msg.ti.com) at Texas Instruments. He talks palladium. 2 Review the archives on Palladium. 3 I think you're running light on temps. Eut
Electronics Forum | Tue Jan 11 07:46:23 EST 2000 | Dave F
Wolfgang: Boy it's tough to convey context in this medium, isn't it? Clipped from our paste storage work instruction, environmental effects on paste are: 1a Avoid excessive heat (over 80� F). It causes flux separation, reducing print quality. 1b
Electronics Forum | Tue Jan 23 19:27:28 EST 2007 | asir
which characteristics? An alloy with similar melting points, wetting, shear force, reliabilities, etc. Indium has an article about 77.2Sn/20.0In/2.8Ag, but was wondering is there any other out there.
Electronics Forum | Tue Nov 21 09:46:19 EST 2006 | jax
I assume you are talking about Sn62Pb36Ag2 solder. You should not see any added concerns when subjecting Sn62 to multiple reflow cycles as compared to Sn63. As compared to Sn63Pb37: Reduced leaching issues Increased Wetting due to lo
