Best way to desolder?

Back in the days when computer memory chips looked like sixteen-legged caterpillars and cost a fortune each, a friend of mine got his hands on a pile of circuit boards with dozens of the things soldered in.

His solution was to grab a board by the corner with pliers and hold it in the flame of his kitchen stove until the solder turned all shiny. A quick flip to bang the edge of the board, upside down, on the edge of the stove, deposited all the chips -- and lots of solder splats -- on the vinyl flooring.

Almost all the chips were good. He was happy; his wife was distinctly

Isaac

These are great boards btw. Very thick and they have half-inch high steel frames on three sides of them.

This sounds great. One more reason I wish I had a gas stove.

Thanks a lot, and thanks to all of you for a lot of good ideas.

Also someone emailed me to suggest a heat gun applied to the solder side, pointing up, and gravity or pliers or a pry to the other side.

Meirman

Takes too long to heat up to solder-melting temperature. Long before that, the components will be cooked.

Isaac

My original question was about relays. I don't think they cook easily, no? And they're the ones I've had the most trouble with, because if there are only one or two wires, I can do that pretty easily. (I don't remove IC's because I don't do volume work or work on the same device, so I can't reuse IC's.)

I actually have a heat gun, but I forgot that I got it broken. I replaced the fan and it worked. Tonight it worked for 2 or 3 minutes before the fan stopped. :)

I'll probably buy a new heat gun soon.

I have to try my soldapullt too. I replaced the O-ring today and it has far more suction. The old O-ring was a full half-millimeter or more smaller than the cylinder it was in. Maybe no suction at all. It had a lot of vaseline or something, that the Soldapullt maker recommends, and I believe him that it won't ruin things quickly. But after a while, vaseline will ruin latex. The thinner the quicker, which is why they recommend against it for condoms. O-rings aren't that thin, and they might not be latex, but in another thread somewhere, I saw vaseline recommended precisely because it made rubber soft. In some situation it made things fit or seal better. If I end up lubricating this o-ring, maybe I'll use KY jelly.

And the propane torch.

And the liquid flux with the solder-wick.

Four things to try!!

Thanks a lot you guys.

Meirman

Don't use a water soluble lubricant - silicon lube is best for the O-ring. That's what Soldapullt includes with the rebuild kit.

in another thread on *another* subject.

OK. I have that too.

But I'm pretty sure also on the soldapullt webpage they recommended vaseline for some reason.

Yeah, it does. I wonder why:

"1. Open the unit (it simply twists apart) and remove any solder that has collected inside.

1. Use a cloth or paper towel to clean the o-ring, the plunger assembly and the chamber.
2. Inspect the o-ring for wear -is the side worn flat where it touches the chamber wall ? If only slightly worn, cleaning and regreasing the unit will be sufficient. If not, replace the o-ring
3. Smear a small amount of Vaseline around the o-ring (strictly-speaking, you shouldn't use a pertoleum product like Vaseline on a rubber o-ring but we've been doing this for years with excellent results).
4. Reassemble the unit and test for proper suction. If the suction is not satisfactory, you can try a little more Vaseline on the o-ring. If that helps, then the o-ring should really be replaced.

For removing surface-mount devices, we suggest ChipQuik"

Meirman

-- If emailing, please let me know whether or not you are posting the same letter. Change domain to erols.com, if necessary.

-------------------- In a pinch, I've used a B.B. gun to blast the solder off a mouse circuit board.

Hey, I had no tools along . .:-(

motsco.

Sorry, but this isn't a Edsyn (manufacturer of Soldapullt (tm)) web page. Use the instructions you see here at your own risk. Once again, I'd recommend silicon lube.