How do I get a stainless pin out of an aluminum masthead?

[Yojimbo]

I would apply heat as a last, but maybe necessary, resort. Soak it well with penetrating oil and let it sit awhile. Get a strong "F" clamp- a Bessey clamp would be the right tool- and a socket larger than pin diameter and one smaller the pin diameter. Arrange the sockets on each side of the pin and use the clamp to have the smaller socket push the pin through the clevis and the larger socket will allow it to get through part way of the clevis. Once you've got it to move, you've broken the hold the corrosion has on the pin and tapping it out the rest of the way should be fairly easy. If it just won't budge, heat it sparingly with propane and reapply penetrant- do this 2-3 times if necessary, and reapply the clamp and sockets to get the pin to move each time.

[skenn_ie]

Very often, with great difficulty. Stainless and aluminium, in a salt environment will fuse together. You may have to drill it. Not easy at the best of times, but especially so if the mast is stepped. Cobalt of titaniun coated bit. Cobalt is very brittle, so any bending force is likely to break it. Cutting compound helps a lot. Even if you drill most of it, the 2 metals may not separate.

[Bloodhound]

Originally Posted by roverhi

Use the jumper cable/battery trick to heat the pin/aluminum and or MAPP gas torch. Heat, quench with penetrating oil, repeat many many times, support the mast head and tap pin with a hammer and/or try twisting with vice grips, repeat as necessary. Do not mindlessly beat on the pin as you can mushroom the head and make removal impossible without removing the mushroom with a file. The mast head needs solid support direct to the ground. Without that the mast will flex and absorb the blows of the hammer, blocks or a 2x4 cut to length directly under the masthead will do the trick.

Most effective penetrating fluid is equal mixture of Acetone and Automatic Transmission Oil.

Jumper cable trick to heat up fasteners.

Hook jumper cables up to the battery as you normally would. On the other end put a bolt (1/4" x 2" bolt works fine) in the postive lead clamp of the jumper cable. Clamp the negative lead as close to the stuck fastener as possible. Touch the bolt in the positive lead clamp to the head of the fastener. You set up what is essentially an arc welder. Will heat the fastener to cherry red if left in contact long enough. It also gets the fastener way hotter than you can with a MAPP torch. It works really well as it only heat up the area of the fastener while not burning up the surrounding country side like you do with a torch. It is really the only way to get serious heat to a fastener if there is painted surfaces or plastics close by. Quench the heated fastener with penetrating oil. Try to remove the fastener with an impact driver, either manual or power. Repeat the process till you break the fastener loose. Other than using the trick to remove all the fasteners on a 44 year old mast, used it to get corrosion welded bolts out that passed through substantial aluminum castings on my self steering vane.

Having said the above, the hardest fastener to remove is not one that is threaded into aluminum but one that simply passes through an aluminum casting like cleats, etc. Getting the bolts out of the self steering casting took something north of 25 iterations, heating with the jumper cable and quenching with penetrating oil over many days. A good idea to coat the shaft not just the threads of any fastener in aluminum cleats or castings with Lanocote, TefGel, or other long lasting lubricant.

I'll second the Lanocote as a preventative. Haven't tried moving the pin in the tabernacle after 10 years, but have been coating other fittings with Lanocote and never have trouble moving them. Ten years ago the pin at the tabernacle (stainless through aluminium) was solid. Penetrating oil and a 5 lb hammer followed by a new pin solved the problem.

[gonesail]

a C clamp done the right way might coax it out .. like the OP said.

[Mickeyrouse]

As you have found, there is quite a reaction between stainless and aluminum. I have found that heating the aluminum slowly with a Burnz-o-matic torch ( or something similar) can be effective at freeing up stainless fasteners in alloy booms. Don’t get in a rush, and constantly tap the stainless pin. What happens, the aluminum and stainless have different coefficients of expansion, and repeatedly heating and cooling, along with the tapping, will eventually break the corrosion barrier. That corrosion (aluminum oxide) is not strong, but over time has filled and expanded the micro gaps between the pin and the hole in the fitting. If it doesn’t happen immediately, drench the effected area with penetrating oil, letting it soak as long as you can make yourself- like, say, overnight. Keep at it- you don’t have to demolish the item with a sledge- you’re just trying to create tiny cracks in the corroded area that will either let you move it, or at least let the penetrating oil do it’s thing. When you start the torch drill again, don’t be alarmed at the smoke- that’s just the Liquid Wrench burning off.

[Cheechako]

If you DO get it out, coat it with Lanolin when re installing it. Or anti seize. But lanolin wont wash out. It will get crusty eventually but should keep the interface clear of corrosion.

[Reefmagnet]

Tefgel is the goop made specifically for dissimilar metals and antisieze applications

[egodsey]

Three observations:
1. I would NOT heat any of assembly with a torch.
2. The preferred method would be to press the pin out. This could be effected by removing the entire masthead assembly from the mast and taking it to a machine shop ... or by finding (or fabricating) an appropriate hand press.
3. The ONLY way I would use a hammer would be with a properly sized drift on the SS pin ... in conjunction with a high mass (steel?) backing plate that has an appropriately sized hole in it for the SS pin.

[Icarus]

Soak it with some penetrating oil.
Give it a good whack back and forth
If all fails warm it up and hit the pin.

[Don C L]

By George, it worked!
OK this is only a minor thread drift because I am talking about a stainless pin stuck in the aluminum head of a spinnaker pole.
1. Soak entire head in weasel piss (equal parts acetone and automatic transmission fluid) for 2 or 3 days (I don't know how much of this is necessary, it's just what I did)
2. Bed entire head in dry ice for 15 minutes. Try twisting it with pliers. Nothing. Tap on it backwards LIGHTLY (stainless will mushroom and then things are going south.) Still nothing. Lightly try to tap it back (have to poke a screwdiver in the end to get at it. Still nothing. Try twisting again. Nothing.
3. Bed in dry ice again. Try twisting and tapping. Nothing. Get frustrated.
4. Boil a kettle of water.
5. Pour boiling water over the pin SLOWLY until the head goes from very cold to very hot.
6. Try twisting again. Notice slight movement. Wipe eyes. Adjust glasses. Look again. Yes, it did move! Rotate back and forth as it is able to move more and more. Spray with (well in my case all I had at this point was chain cleaner, which worked pretty well!) Rotate more. Try tapping. The pin slides in a mm.
Tap back out. Repeat. Add more weasel piss. Repeat.

And slowly it is recovering, but the difference in this case is that the pin has a spring on it inside the head and apparently the corrosion of/on the spring needs more work and time to knock it off, but it worked! Whoever invented weasel piss should get the Nobel prize! But I think step 5 was the key; go from dry ice cold to boiling hot.

[C420sailor]

When I have exhausted all other methods, I go to the following:

I weld a nut to the big end. Fill the inside of that puppy with wire/electrode/filler rod. Let cool. More weasel piss. Pop an impact gun on and go to town. Works great on stripped/broken bolts too.

[Jim Cate]

By George, it worked!

way to go, Don! WP is soooo satisfying to use... mix it up yourself and Lo! works better than the expensive stuff in the (always empty when ya need it) spray can.

No excuse now to not fly the kite!

Jim

[Icarus]

Ridiculous

[Icarus]

Oh, I just hop down to the cornerstore and get a bag of dry ice...

[Jim Cate]

Originally Posted by Icarus

Ridiculous

Not sure just whom you are disparaging here, Icarus, but if it is me, well, how come? Just what is ridiculous?

Jim