Using heat to separate parts

I have an old electric soldering iron (100 watt) that needs a new tip. The tip is held on by a small slotted machine screw that is VERY stuck in place. The screw is headless roughly 1/8" in diameter with the slot itself below the surface of a collar that acts as a carrier for the copper tip. The tip itself has a pyramid shape at the end of a 3/8" round shaft. From its appearance, it looks like if I can get the screw out, the collar and tip will come off of the iron as a unit.

I don't want to drill the old screw out to remove it since I might destroy the soldering iron in the process.

I've heard that it is possible to use heat as a way of encouraging metal parts to become unstuck from each other. Is that true? Do you think it would work in my case? What is the technique?

Thanks.

Gary

Reply to
grice
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Heat. Let cool. Repeat, usually adding penetrating oil. If you have Kroil, you don't need me to tell you how to use it. If you have WD-40, don't waste your time with it - it's not a penetrating oil.

My favorite way to get out stuck threaded items is to cut out a square of sheet steel (needn't be thick) maybe the size of a postage stamp, then punch a hole in the middle about the diameter of your stuck fastener. Set it over the top carefully, clamping it in place if possible, and then use your MIG welder to weld it to the fastener. Start the wire right down the center of the hole, and as it begins to arc, spiral the wire out in a small circular motion - won't take long. Then put a decent sized nut, maybe 1/2", on the sheet metal and weld it down, then use a wrench to back out your fastener.

This would be very risky indeed if the body the fastener is stuck in is also made of steel - in that case you'd have to be really certain you didn't weld it in.

I don't agree that you can't drill it out. Get a left handed drill bit, start a bloody great center punch mark in the middle, and drill it. Then use an easy out, in combination with heat/cool cycles and application of real penetrating oil.

Actually, the first thing I'd try is an impact driver type of screwdriver, the kind you hit with a hammer.

Grant

Reply to
Grant Erwin

wrote: (clip) it is possible to use heat as a way of encouraging metal parts to become unstuck from each other. (clip) What is the technique? ^^^^^^^^^^^^^^^^ Plug it in?

But seriously, if you are really fearful of drilling, use a Dremel type tool to remove the set screw. You'll probably destroy the threads on the soldering iron body, so you will have to drill and tap to a larger size, or in a new location.

Reply to
Leo Lichtman

Sounds like you are describing an American Beauty soldering iron. I had the same problem with mine a few years ago, and I got the old screw loose with a combination of soaking in automotive brake fluid (the old fashioned non-silicone type), alternate heating & cooling, and finally tapping with a screwdriver and hammer. It took several days in my case, but the tip had been in there since before I bought the iron in 1967. Brake fluid is one of the best penetrating fluids, but it has a tendency to absorb moisture from the air and it should be carefully cleaned off the threads after you get the screw out, or it could cause the screw to rust in place again. I put a coat of a high temperature anti-seize compound on the replacement screw, and also used a flathead phillips screw in place of the original headless screw to make it easier to get out next time, just in case it sticks again.

Mike

Reply to
KyMike

Exactly right!!! I will give your brake fluid suggestion a try. Thanks.

Gary

Reply to
grice

The best solvent for rust is water. Heat it up, and quench it - several times. Candle wax helps too - get it hot and melt wax into the threads. Or get some ionic penetrating fluid like Lloyds AD2000. Haven't seen it on the net, but it WORKS.

Reply to
clare at snyder.on.ca

According to :

And if it is an American Beauty, then the screw *only* allows the copper slug which makes up the tip to be removed. The ring will stay put as part of the enclosure around the heating element.

Those are good irons - -don't destroy it, I've got a 750 W one which I use from time to time - and which I used to use to quick-defrost an ancient (just post WW-II) fridge in the lab at work. :-)

Good Luck, DoN.

Reply to
DoN. Nichols

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