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.

[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.

[weisan]

to fool around with a frame that i took home from the shop yesterday with a stuck seatpost....so far it's proven to be a worthy opponent that doesn't give an inch.

[MikeD]

I think I would try that Freeze Off stuff or pack the seatpost (after cutting of the top) with dry ice, before resorting to more radical measures like hack sawing it out. Aluminum has a different coefficient of expansion than steel, and freezing it should make it shrink (in theory anyway).

[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.

[nickrenfro]

Go back and try the caustic soda technic. Close up any hole there may be - BB, downtube, etc - and then pour that **** to the top, let it bubble off a bit, top it off, and then seal shut the top of the seatpost.

I just recently did this with an older cross frame - took about 48 hours, but it finally worked. I exhausted all other methods and this was the best(because it worked) forsure.