Thanks, Kathy...

I'm blowing the whole high temp. idea out the door, based on a number of issues, not the least of which is what
it's likely do to the components (including the board) associated with this mess. 

I've never heard of the latex masking before, but it sounds like a very creative way to deal with something in a 
"last ditch" manner.  It probably felt great to finally come up with something that solved the problem.  I just hope
I never had the same problem. 

It looks like either I'm going to need a selective soldering pallet or I'm going to be glueing bottom side SMT with 
topside through-hole hanging on for dear life with clinched leads. We've tried printing paste before adhesive to 
reduce skips from shadowing on bad layouts, but the components apparently were squirming around a little due to adhesive contraction during cooling (while the solder was still above liquidus) and it really mucked up the connections.  Not pretty. 

I sure like this forum.....

Steve


-----Original Message-----
From: Kathy Kuhlow [mailto:[log in to unmask]]
Sent: Friday, September 06, 2002 1:47 PM
To: [log in to unmask]
Subject: Re: [TN]


I have seen a couple of alternatives: paste, adhesive application (not screened on) and then reflow.  Then in the wave process use either a selective solder pallet or wave as is and take the rework for bad layout issues.  Or another option is to assemble with paste on the solder side w/o adhesive and use a pin to paste for the through hole parts.  Maybe even a solder doughnut with a gel flux for the through hole parts.  Also tried once on a really bad design latex masking over all of the sm parts on the solder side.  We had to use a lot of mask though so the parts inside the mask wouldn't partially reflow.  It was pretty successful.  Even programmed up an older adhesive dispenser to dispense the latex mask unto the PCB.  Had to go back over some spots 5-6 times to get the right thickness of goo.    

Be careful with the high temp paste and the through hole parts thermally.  

Have fun

Kat

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