Electronics Forum | Mon Jan 31 14:08:26 EST 2000 | Ashok Dhawan
I have got a number of assemblies back from a customer with feedback that the solder fillet is less than 25% of chip height per IPC-Standard-610B Class 2. Most of my joints are having good wetting but fillet height does not meet min ht requirement of
Electronics Forum | Thu Jan 13 14:16:32 EST 2000 | mike d
Michael, Good afternoon. My experience with the frameless stencils has been less than optimal. I tried the universal stencil system about a year ago and these are my experiences. 1) The stencil manufacturer supplied me with a free frame to try ou
Electronics Forum | Tue Dec 28 10:57:53 EST 1999 | Amy Castor
I have tried the water soluble flux and the aqueous cleaners but I got the same results you did; horrible corrosion and a white flaky mess. I know exactly what you're talking about. We do a lot of hand soldering around here, and the magical solutio
Electronics Forum | Wed Dec 29 14:30:28 EST 1999 | Dan Woodward
I am not sure if I have seen an article comparing solder joint strength Vs pressfit although I am sure this has been researched by literally hundreds of companies before they felt comfortable going to pressfit. I know one of the issues with solder is
Electronics Forum | Mon Dec 20 19:09:54 EST 1999 | Chris
If your flex circuit is only populated on one side, you can have the PCB vendor palletize the flex for you. What you do is have the flex circuit laminated to 062" FR4 using a thermoset adhesive like Dupont WA. Standard flex circuit adhesive. Howev
Electronics Forum | Fri Dec 17 16:25:05 EST 1999 | Brian W.
I used an off-line paste height measurement device to control my paste process. I did not inspect every board, just a random sample once an hour. I have used both manual and automatic devices. I like the automatic becuase: 1 - I have no "operat
Electronics Forum | Thu Dec 16 06:59:43 EST 1999 | Christopher Lampron
Calvin, We have found several reasons for solder beading occurance. We have found that solder balling is usually directly attributed to the reflow profile while solder beading is usually (but not always) a result of either excessive solder paste volu
Electronics Forum | Thu Dec 09 23:57:41 EST 1999 | Jeff Sanchez
Mike, A drag solder system is not so bad. If it's not discoloring the silk screen , damaging your parts or blistering your boards than it looks like a safe bet. I am not sure what other components you have on the boards besides the LED's? But the
Electronics Forum | Fri Nov 26 06:18:18 EST 1999 | stefano bolleri
Jeff & Ted, we have used a dispensing system too and yes, I agree, we are not too happy with the results. Not at the point that it doesn't work, though. I think our problem basicly is that we have selected an entry-level dipensing system. We are app
Electronics Forum | Sun Nov 07 10:54:21 EST 1999 | Steve Thomas
We're looking at redesigning our stencils to facilitate better (well, it's pretty much non-existant, so any improvement is a big leap) release from fine pitch apertures. Currently we have perpendicular walled laser cut apertures. We'll be having
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