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

[Foredeck]

Soak it for a day or two in a bath of white vinegar.
Undoes the galvanic action that occurrs seizing alu/stainless connections.
Have used this often with great success and little violence heat cold .
Good luck

[Bill Seal]

Use a hefty C clamp and deep socket to squeeze it out. Poor man's arbor press.

[garyfdl]

Lot's of good ideas!

I especially like the C-clamp socket /arbor press. Try after heating or soaking the parts.

A word on heat be careful! Aluminum melts at about 1200 F. That's less than half that of stainless.

I would not bang on the pin directly with a hammer. Use a drift, or even a center punch. There's less risk of breaking the mast head or mushrooming the pin.

Good luck!

[Jdege]

Originally Posted by Bill Seal

Use a hefty C clamp and deep socket to squeeze it out. Poor man's arbor press.

I was thinking exactly that, after inserting wedges to keep the two sides of the masthead from collapsing.

What I've done so far is to give it a good spray of PB Blaster and let it sit.

[Jdege]

Originally Posted by garyfdl

I would not bang on the pin directly with a hammer. Use a drift, or even a center punch. There's less risk of breaking the mast head or mushrooming the pin.

The masthead is still connected to the mast, and the mast is sitting on a couple of sawhorses. Beating on it with a hammer would simply lift the other end of the mast.

I'm going to see if I can get the masthead disconnected, and bring it into the shop.

[kryg]

You need to heat the pin till it is NEAR red hot. I had my mast totally stripped to rebuild it. I could not do it without the heating the pins and bolts. Don't try to remove the pin without first using a Map blow torch see attachment. Also my mast stripped note the through holes to attaché the rigging. everyone of thoughts holes had a stainless steel bolt or large though pins , Something I learned the mast was build without out s/s bearings inserts on the stay holes and aluminium chain plates my boat is build in Aluminium. when you replace the pins and bolds use quality Lanotec grease and insure your stay attachments have bearing inserts before refitting your rigging attachments. . PS. I took the opportunity to change my rigging to Dyneema, saved about 250 kilos in weight.

Good luck with it.

Originally Posted by Jdege

I bought a boat last fall, so of course I'm doing boat work.

My current problem is inspecting and maintaining the mainmast head.

I have the mast sitting on sawhorses, and I'm removing and inspecting/cleaning everything.

I have a forestay held in place by a stainless pin fit through the aluminum masthead. (See the attachment).

There were split rings on each end of the pin, holding it in place. I've removed one, but the pin seems solidly seized in place.

How do I get it out?

[patprice]

Originally Posted by Pandor

Remember the three rules:
1) Always use the right tool for the job.
2) A hammer is always the right tool.
3) Any tool can be used as a hammer.

And if that hammer does not work use a bigger one...

[captlloyd]

Use PB Blaster first, heat as a last resort. You very well may not need heat.

[GreenWave]

I have a similar problem with pins going through my boom and holding the sheaves in place for my outhaul. One sheave broke so I need to get the pin out and replace the Delrin sheaves. The pin is corrosion “welded” in pretty good. Lots of good ideas here and noodling on which may work best for this scenario.

[JC Reefer]

Im in line with others talking about heat. Be aware that you can melt items that the heat extends into.

[mlydon]

That pin looks like it sticks out far enough that you could get a good grip on it with a pipe wrench and spin it.....after dousing the connections as others have suggested.

Matt

[Celestialsailor]

Originally Posted by deblen

Heat the aluminum with a propane torch-both sides.
Hammer on the pin.
Len

Originally Posted by Manateeman

Heat...lots of heat on the stainless.
Mark

Actually heat on the aluminum. It expands at 6 times the rate of Aluminum and it will breakdown the oxide.

Originally Posted by WildChild

Heat and let cool down a few times and tap with hammer.

Originally Posted by JC Reefer

Im in line with others talking about heat. Be aware that you can melt items that the heat extends into.

I have been a Toolmaker/Machinist for 45 years. All the above quotes show the knowledge needed for the task.
Just beating on it with a hammer will only begin to bend and mushroom things.

While Kroil and other magic snake oil can help, use the heat first. If propane is too wimpy, try map gas. I use Oxy/Ace torches VERY carefully. If I am heating up steel, I use my smallest brazing nozzle. If I'm heating aluminum around a pin, I use my larger brazing nozzle. Aluminum shaft seized in an aluminum casting (windvane) I use a helper, heat the O.D. casting and the helper drives out the shaft before it has a chance to heat up.
Hope this helps.

[ixnax]

Originally Posted by captlloyd

Use PB Blaster first, heat as a last resort. You very well may not need heat.

Bingo. That's why I have a 5 point plan.

1. Patience. It's a boat job so you have a lot more work besides the pin.
2. Spray it with PB Blaster Penetrating Oil. Go do something else the rest of the day. Have some beers.
3. Gently try to turn it. If that works continue until loose. Otherwise, curse the goddamn thing and spray it again with PB Blaster. Scream at the dog on the hill to shut the XXX up. Have more beers. Call it a day.
4. Try again to get it free with more gentle turning. If no, use a hardwood dowel to tap it out with a hammer. If no, spray it again with PB Blaster and walk away.
5. Try again to tap loose. If no, and if you've had it with that dog, go nuclear. Start with propane, continue with MAP gas and finish with oxy-acetylene PRN. Just know that you stand a fine chance of causing a worse problem.

[Luvboats]

Heat……
Beat……
Repeat……..

If that doesn’t work then simply……..Cheat!

[CdS2 Roland]

Hello,
Got a similar issue when I removed all winches on my 35 years old aluminium SV. IMO point the center of the pin head and drill it out with a good titanium drill bit for SS. Drill slowly from both sides. Drill bit size just a little smaller than the pin diameter. Break the pin head and use a push pin and hammer to finish the job.