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Thanks Bird, planning on doing it anyways so I'll give it a shot.

I've used ammonia as follows:

- take the cranks and bottom bracket out of the frame
- put the frame upside down
- pour about 1/2 cup ammonia into seat tube thru the hole where the eat tube meets up with the bottom bracket shell.
- let it sit for a week.
- try to remove the stem.

If it doesn't come out, use some more thermal cycling to try to loosen it up:

- put a bowl of ice water (mostly ice) on the floor with the frame upside down in it, so the seat post is mostly in the bowl
- let it sit for an hour or so
- try removing the post
- take it out of the water and use a hair dryer or heat gun to warm the seat tube and post up. try removing again
- repeat the ice bath / heat gun steps 2-3 times

Use a hacksaw blade to cut a vertical slot into the post.  Carefully cut it almost all the way through without damaging the seat tube. Once there is a big enough slot, clamp it in a vise and turn it out.

From my experience, take it to a machine shop. Unless one of these tips works for you. The aluminum corrodes (thus expanding the post size) and bonds with the steel. I suffered through this once. Got past the point of no return (meaning I'd destroyed any bit of a useable post by clamping, drilling, slotting, etc) and literally took out the post in a thousand pieces.

ace inc wrote:

Use a hacksaw blade to cut a vertical slot into the post.  Carefully cut it almost all the way through without damaging the seat tube. Once there is a big enough slot, clamp it in a vise and turn it out.

I don't understand what the vertical slot is for. I can clamp it in a vise right now and twisting it out was the first thing I tried. The frame was flexing too much so I felt like I had to back off. Please elaborate on the Vertical slot?

skaman wrote:

Dissolve the aluminum seat post with Lye (sodium hydroxide).  Takes time but people say it works.  I've used Greased Lightning which contains Sodium Hydroxide to quickly remove anodizing.

There's another lubricant that people have been using to remove stuck/frozen items.  It is made by CRC and called Freeze Off.  Costs about $6-7 a can from the local auto parts store.  I've personally used it on frozen bolts.  Way faster than Kroil or PB Blaster.

So the lye won't hurt chromoly or nickle plating but it'll completely dissolve aluminum? How much time are you thinking it'll take?

  Thanks for the tips!

Great stuff, THANKS man!

blackflag wrote:

ace inc wrote:

Use a hacksaw blade to cut a vertical slot into the post.  Carefully cut it almost all the way through without damaging the seat tube. Once there is a big enough slot, clamp it in a vise and turn it out.

I don't understand what the vertical slot is for. I can clamp it in a vise right now and twisting it out was the first thing I tried. The frame was flexing too much so I felt like I had to back off. Please elaborate on the Vertical slot?

Insert the hacksaw blade right into the seatpost and cut the length of it (up and down).  If the blade wont fit down the post, you can try a small round file.

Keep sawing or filing until you have cut a channel along the whole length of the post. 

It's slow going, but I managed to remove a frozen aluminum seatpost that had broken off flush with the top of a chromoly frame.

Hope this helps!

See, now the stem won't let go of the post....

Okay, I never bothered to separate them.

XJguy wrote:

What you have going on there is galvanic action, the two are fused.

I discovered the hard way (almost disintegrated my Shimano DX pedals ) that the Drano crystals will dissolve aluminum very fast.   It also bubbles and heats up like crazy.  I dont know if it will effect the nickel plating so if you use this method do so with caution so as not to spill it on the finish.    Mix some crystals in water and carefully pour into the seatpost.  Dont fill too much because it does bubble.   Seatpost will dissolve enough for you to be able to get it out.

Use protective goggles.

Do not forget that vertilation is equally important.

Lye wont harm the ferrous steel, but the heat reaction could be potentially a problem and nickel is a transitional metal ... Look to see if drano harms nickel on the interwebz

WOW!!!!  there is a set i have it is a pipe extractor set. the best money i ever spent. works great !really you must own this or know where to get one. i think you can rent the set from your local auto parts store. make life sooo much easier. trust me guys check in to it. ive pulled 3 very very very stuck seat post out with it. 80' motomag 83' predator. the worst of all was a fluted seatpost in a 83' DB silver streak. that i found at my local scrap yard. it had been there a long time.then if that does not work machine shop tell them you want it line board out.  also TRI-FLOW the answer to everything