On Mon, 3 Feb 2003, llile@SALTONUSA.COM wrote:

*>I made another try with the desoldering iron/air pump, but without
*>satisfaction.  This time I stuffed copper desolder braid up into the iron
*>for better heat transfer.  I packed it tight, and it restricted airflow
*>somewhat.  Insulated the soldering iron with fiberglass braid, and cranked
*>it up to 140volts, which gave me about 60 watts.   I was able to melt wire
*>solder easily, but wasn't satisfied with the results on the board.  I am
*>sure the soldering iron would burn out rapidly at this voltage.
*>
*>I went back to the E-Z bake method, and had some success.  I had a
*>thermocouple buried in my board, which made it easier to control.  I baked
*>it at 60C for four minutes, (actually just let the board sit in a
*>preheated oven shut off) then cranked the oven up, which brought it to
*>215C for over one minute.
*>
*>I found there was a lot of solder balls left on the board, and I had to
*>mechanically remove them quite vigorously.  Underneath was a good solder
*>joint.  I tried a toothbrush, which would not touch it, then the end of a
*>needle, which scraped it off pretty well.  I finally just got out a fine
*>wire brush and removed the stuff wholesale.  This is never a problem with
*>a hand soldering iron.
*>
*>Do other people have to remove this stuff after reflow?  Does it seem to
*>take a vigorous amount of work?  I would have a hard time applying less
*>solder, using a syringe, I just touch the pad, don't squeeze any on at
*>all.  I added extra flux to the board, and I am using a combo solder, RMA
*>flux.  It has 2% silver content, which might make it a little higher
*>temperature solder.

Obtain a bottle of flux remover (I use a spray can tm CRC, with built in
brush). Brush the board with the stuff, let it sit for 1 minute, blow if
off with compressed air. Done.

Peter

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