Electronics Forum | Fri Mar 06 16:17:38 EST 2009 | aj
whats your board finish?
Electronics Forum | Fri Mar 06 10:46:35 EST 2009 | davef
First, we agree with Loco that your QFP is nonwetting, rather than dewetting. Your sceen-shots look like ol' timey SnPb paste recipes. Turn-up the heaterometer dial. Second, on nitrogen: * We kinda think your O2 needs to be around 100ppm with 99.99%
Electronics Forum | Fri Mar 06 10:50:21 EST 2009 | fountain42
Just my opinion but it look's like your doing a great job. i would try another paste. I'm somewhat lucky that we get to use OA's. If your stuck using the no-cleans they are so tempermental. (The nitrogen is making up for the poor paste) Your de-wetti
Electronics Forum | Fri Mar 06 02:47:15 EST 2009 | lococost
Have you tried higher peaktemp? I saw the QFP is sn90pb10, This has a liquidus of 268 - 302 C. A good paste should be able to handle 230C (or more), of course you would need to check your other components peak temp.
Electronics Forum | Fri Mar 06 11:01:53 EST 2009 | dyoungquist
I have attached a pdf version of an article that explains the basics of a nitrogen atmosphere when soldering. It gives some basic guidlines as to when one may want to use nitrogen and what it can and can not accomplish. FYI- I did not write that ar
Electronics Forum | Thu Mar 05 11:53:09 EST 2009 | dcell_1t
Hello to all. for certain time, we have been struggling with some issues on a PCB where have tombstoning on 0402 components (due to pad design) and dewetting in qfp256 0.5 mil pitch (discussed on another threads on this forum) component, we have pro
Electronics Forum | Thu Mar 12 06:37:48 EDT 2009 | gregoryyork
I agree you are too cold for the profile get it up to 230C and possibly allow it to dwell a little longer in preheat as opposed to pushing up the reflow zone only. Sn90/Pb10 melts at 220C so 2C hotter than your profile so you are reliant on it alloyi
Electronics Forum | Mon Nov 26 16:07:56 EST 2012 | jerlong
Greetings, Does anyone know where to find a tape and reel flatness specification? Looking at the EIA 481-B standard, there is no reference to the tape flatness (the images shown may "imply" flatness from one side of the tape to the other, However I
Electronics Forum | Fri Feb 11 19:07:16 EST 2005 | primus
We are also looking for AOI machines, pre- and post-reflow. We already tried one machine from the UK (I don't remember the name, I perfer to forget we ever had it) and they told is it would do everything we wanted. Maybe so, but not well enough. It s
Electronics Forum | Thu Apr 09 20:18:31 EDT 2020 | jlawson
Can not speak for CircuitCam is made by Aegis Software I veliveve sound like need to get understanding of how tool is supposed to work to extract-create centroid positions. Using Gerber Only is a pattern match and cacluate logic process - ie make pac
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