Electronics Forum | Thu Dec 05 11:04:27 EST 2002 | slthomas
They're IR, bottom side only. Frankly wave solder is not my forte (there are those that would claim nothing is), but I've personally been tasked with developing a process to do reliable, high volume bottom side SMT, so I'm drawing a lot from the tec
Electronics Forum | Tue Dec 03 18:31:45 EST 2002 | slthomas
At the price of Durapol we'd never get the OK to have them made. The Al fixtures are cheap and a quick turn local item. As dense as the pth parts are I also don't think there'd be any room for any holes which I really think is the answer as far a
Electronics Forum | Thu Aug 23 16:28:14 EDT 2007 | grics
I want to get a collective opinion from the forum... I was always under the impression that Humidity at SMT can be a disaster and can cause solder balls... But what about at the Wave/Selective solder? If every board or almost every board has solder
Electronics Forum | Fri Aug 24 09:29:08 EDT 2007 | jgrootkoerkamp
Solder balls with wave soldering can have different causes. The two most important are the solderresist and the flux. I have similar problems, after changes the flux type 90% off all solderballs are gone. KR, Joris Groot koerkamp
Electronics Forum | Thu Aug 23 22:41:54 EDT 2007 | davef
Water soluable fluxes are quite hydroscopic. If you keep RH below 50 percent, solder balling caused by humidity should be minimized.
Electronics Forum | Fri Aug 24 12:39:59 EDT 2007 | hussman
I would say no, unless your machine is in extremeconditions. You may want to check your flux / preheat out as well. If you are leaving a lot of flux on the board at wave, it may be boiling - which can cause solder balls.
Electronics Forum | Tue Jun 01 19:23:15 EDT 2004 | Ken
profile it for the tin/lead paste. The tin in the solder paste will begin to disolve the sac ball. This is exactly the same scenario as 90/10 (80/20)high temp balls found on ceramic bga and many super bga devices (except the sac balls are now tin r
Electronics Forum | Fri Aug 24 11:03:15 EDT 2007 | hussman
I agree with Joris. But to add to his comment, the type of finish also has a direct affect to your wave solder process. Going from a gloss finish to a matte finish may help a lot. As for humidity affecting your wave - I doubt it. I use a water
Electronics Forum | Tue Aug 28 11:12:23 EDT 2007 | grics
This is what I was thinking, but I am being beat up pretty badly by the selective solder. Ambient temperature is anywhere in the the neighborhood of 76 - 80 degrees F. I am not sure of the RH, but I wouldn't think that would be my issue... One of
Electronics Forum | Tue Jun 01 19:25:19 EDT 2004 | Ken
...oops part 2: I will assume a sac 350 ball??? 217-218C this will completely reflow the ball and form a "normalized" joint with a collapsed structure.
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