Stuck Seatpost

[malcolm]

Originally Posted by p nut

My attention's been diverted. I'd love to restore a 60 some day.

Not to derail. It's a '90 62 and needs some work but I've got all the running gear done and essentially new, suspensionm, steering components, brakes, all bearings and seals, should be able to drive in a week or so then on to the interior.. I've got a really nice '97 80 on the way.

[Stephen2014]

...or a triangular one if they got no square ones in stock as you still got 3 cutting corners. I just happened to have a square one among my tools.

[bikinchris]

The reason I say to use Lye is my own story. I had to get TWO frozen seatposts out that broke when I clamped them in a vice and turned the frame:

http://forums.thepaceline.net/showthread.php?t=145859

[mjf]

Originally Posted by F150

Perhaps I wasn't patient enough, but Coke didn't work, ammonia didn't work, PB Blaster, Kroil, 3n1 mixed with K-1 didn't work. Nor did force, via impact or torque. Tired of the hacksaw routine, so went to caustic lye. Job done. Not without it's challenges, but it worked.

The gases evolved in dissolution of aluminum (hydrogen) are flammable, explosive only if confined. Do it outdoors, wear proper PPE and DO NOT mix the caustic lye and water by shaking in a sealed container. Swirl in open cup. Exothermic reaction, sealed container go boom and you will be sporting some new chemical burns. Guys in a plating shop don't worry about hex chrome (carcinogen) but give sodium hydroxide serious respect.

Don't mess around with NaOH. Your eyes won't grow back.

Originally Posted by bikinchris

The reason I say to use Lye is my own story. I had to get TWO frozen seatposts out that broke when I clamped them in a vice and turned the frame:

http://forums.thepaceline.net/showthread.php?t=145859

100% the last resort to go to with a stuck alu post in a steel frame.

Had a stuck post in what is my daily commuter; and couldn't budge it no matter what I had tried.

Stripped off the excess parts from the frame, and sealed it up, piped in a mix of water/lye and let it sit for a few days. Vinegar to neutralize the solution after the fact.

[adamhell]

if i have to go to lye, I might just trash the frame.

[Satellite]

Originally Posted by adamhell

if i have to go to lye, I might just trash the frame.

Why not go for it nothing to lose just be careful that's all. If the dunce that closed the lid on the bottle can do it so can you.

[adamhell]

after multiple days hacking away at this, i finally broke down and bought a drill. i wish i woulda done this sooner. it has helped significantly. there are now several inches of seattube without seatpost in them! it would help if i had a large set of varied sizes of drill bits, but these huge fat ones are expensive.

[Satellite]

I think I would of broke down and bought the lye.

[Tony]

Originally Posted by adamhell

after multiple days hacking away at this, i finally broke down and bought a drill. i wish i woulda done this sooner. it has helped significantly. there are now several inches of seattube without seatpost in them! it would help if i had a large set of varied sizes of drill bits, but these huge fat ones are expensive.

I would skip the large drill bit and use a sharp chisel. Split the remaining seat post into section and remove.

[YoKev]

Vertical slits with a hacksaw blade. It may take some time but it'll be worth it IMHO. That's a nice frame! I have surgically removed three posts and a quill stem with this method.

[adamhell]

Originally Posted by YoKev

Vertical slits with a hacksaw blade. It may take some time but it'll be worth it IMHO. That's a nice frame! I have surgically removed three posts and a quill stem with this method.

so let me get this straight - i have to remove the hacksaw blade and dip it down into the seat tube and start sawing away? how do i get leverage on the bottom end? this seems like it would never work. maybe i am misunderstanding something????

i'll try it later tonight

[Gsinill]

If the part that is sticking out is useless (which it seems it is since the vise method didn't work), did you try to use a mallet to drive it in further?
I am sure if you get it to move just a little, it would free it enough to then twist it out in the vise.

Man, and I thought my seized BB is trouble!

God Luck!

[adamhell]

Originally Posted by Gsinill

If the part that is sticking out is useless (which it seems it is since the vise method didn't work), did you try to use a mallet to drive it in further?
I am sure if you get it to move just a little, it would free it enough to then twist it out in the vise.

Man, and I thought my seized BB is trouble!

God Luck!

this is a good point. maybe i will try this.

[sjpitts]

Are we talking about an aluminum seat post in a steel frame? The problem with applying heat in that situation is that the aluminum expands faster than steel-- which would seem to make the problem worse, not better.

The one time I had this problem I spent a few days soaking it with penetrating oil, trying to get the oil to flow down between the seat post and the frame.

Then I wrapped the exposed portion of the seat post in dry ice. Basically, I crushed the dry ice, put it in a ziplock bag and wrapped it to the seat post. After 10 minutes or so the seat post was nice and cold and I was able to break it loose with big ass wrench.

YMMV

Again, I think this method works best with aluminum seat posts and steel frames, given their relative coefficients of thermal expansion.

Jared

[adamhell]

Originally Posted by sjpitts

Are we talking about an aluminum seat post in a steel frame? The problem with applying heat in that situation is that the aluminum expands faster than steel-- which would seem to make the problem worse, not better.

The one time I had this problem I spent a few days soaking it with penetrating oil, trying to get the oil to flow down between the seat post and the frame.

Then I wrapped the exposed portion of the seat post in dry ice. Basically, I crushed the dry ice, put it in a ziplock bag and wrapped it to the seat post. After 10 minutes or so the seat post was nice and cold and I was able to break it loose with big ass wrench.

YMMV

Again, I think this method works best with aluminum seat posts and steel frames, given their relative coefficients of thermal expansion.

Jared

yep, alu post in steel frame. luckily the aluminum is getting cut really nicely. there is no longer any exposed seatpost to try your method, but maybe some variation of it will be possible and/or necessary. i'll keep yall updated.