On Tue, 02 Aug 2005 05:35:33 GMT "Michael A. Terrell"
wrote:

Jim, I remove all the solder, one pin at a time. After the pin
cools, I put the side of the tip to the edge of the pin so the remaining
solder will let go without heating the PTH and pull the pin to the
center of the hole, where I let go an let it cool. Sometimes I have to
take a small pick and press gently against the pin on the top side to
free it from the wall of the PTH.

I find that the HP holes are so tight that I can't center the pin in
both the top and bottom of the hole. I've tried a wooden tool, and
often use toothpicks to clear the holes once the pins are out.

if I have trouble pulling all the
solder out of a hole, I add fresh 63/37 solder to the 80/20 that was
used for wave soldering. It now has a lower melting point, and will
come out easier.

I do this too, but I didn't realize that the wave solder was
non-eutectic. Why do they use the higher melting point solder?

One tip: Use liquid RMA flux with the solder wick to reduce heat
damage, and leave about 1/16" of the wick filled with solder when you
clip off the used portion. The solid part allows you to transfer the
heat to the pin, rather than the board so it flows into the braid a lot
quicker.

I've never had much luck with solder wick and PTHs, but I've never had
RMA flux. Where can one buy it?

Another thing, use a board holder to position the PTHs horizontally
so you can get the solder out easier.

That's another trick I never tried.

Thanks for the careful explanation.

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Jim Adney
Madison, WI 53711 USA
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