raleigh technium pro stuck seat post
 

title says it all.

Alloy post
steel lugs
Aluminum main tubes thermally bonded to the lugs.

It is a 26.8 which i believe is the correct size
It will NOT move.

Ive soaked it for about 4 days in pb blaster both externally and internally through the water cage hole.

Heat will do no good considering alloy expands faster than steel and given the frame/lug bonding chances are heating would compromise the frame.

i tried that freeze off crap. Dont bother. It barely dropped the temp at all. i would have been better off with a can of canned air for blowing out computers....turn that upside down and you get COLD. THis freeze off stuff is a waste of 7 bucks and about 2 hours of your life.

anyway...i 3 foot pipe wrench wouldnt budge it

what other options do i have other than cut the seat tube down and hack saw on it. im afraid to do this as the main tubes are aluminum and ill probably end up messing up the frame.

Read up the Sheldon Brown article on this topic. Usually, I give it time, a lot of time. And I use Kroil, which is better than PB Blaster. (some report good success with ATF/acetone mix). And I mount it on my secure bench vise. 99% of the time, that works. 1% of the time, I have to cut it out. Do enough of them, and sooner or later, you will have to cut one out. Hopefully you won't have to do it this time.


Be careful with leverage. Put enough force on the frame with a stuck post, and you can eventually bend the frame or stays. Ask me how I know. So there is a fine line between pushing it hard enough, and pushing it too hard.

Is Kroil that much better that I would spend the money just for this one job? No. But if you plan to work on more bikes, it is worth it.

neat. Ive never heard of Kroil but it appears to be amazing stuff. Spendy ...but amazing. I might just splurge and order some. IM always working on something or another and it will surely come in handy on other things.

Do not heat it! It will melt the metals together! Take it to a local bike shop and get it fixed. Some would call your problem "a simple reapir" and fix it for free!

How did this come out scale? Do tell...

Melting steel and aluminum together??? I don't think anyone ever heats a frame that hot just to remove a stuck seatpost. :rolleyes:

The problem here isn't melting metals, it's destroying an epoxy bond as these frames were "glued" together and even moderate heat can damage it.

Still sitting and soaking with pb blaster. I haven't purchased the other stuff yet.

The 6 inches of alloy seat post sticking out is getting pretty chewed up from the pipe wrench.
My fear is that the alloy is so soft that the post will just snap at a level where I cant get a bite on it any more or even worse....inside the frame.

it is hard to get leverage without risking bending the frame or compromising the EPOXY at the joints. Im hoping this good soak will do it some good but I have doubts.

I might order the kroil and risk the 20 bucks for the can. I can use it elsewhere on other projects if it doesn't work here.

Er, what?

Someone suggested removing bottom bracket, turning the frame upside down and inserting dry ice down the seat tube from the bottom bracket housing.
Haven't tried it myself though.

The other issue with using temperature to remove the post (aside from trashing the epoxy by overheating it) is that both the seat tube and seatpost are aluminium, so they'll contract or expand by the same amount.

Bench vise works MUCH better than a pipe wrench, and allows you to use a little finesse. Pull too hard, and you run the risk of bending the frame (ask me how I know). Depending on the value of the frame, I just go to cutting it out. Tedious, but it does no damage. I did that on a vintage Masi recently. I did not want to risk ruining a $500 to $750 vintage frame.

This makes perfect sense. THe lug is steel...the post is alloy. The alloy would contract faster than the steel. No idea where to get dry ice though.

Google? http://www.dryicedirectory.com/

funny, I have a Technium and had trouble with the seat falling down on me recently.

Patience....and judicious BRUTE FORCE....but in a patient manner. I had my Bridgestone upside down in a bench vice for two weeks, putting PB Blaster down the tube onto the offending seat post. Once a day, add more PB, TAP the seat post a few times, give the frame a little push and pull, and walk away. Two Weeks....didn't know I was THAT patient...the first 3-4 days were the hardest!

Doesn't the aluminium tube run all the way through the lug on a Technium? The seatpost may not be inserted directly into anything steel.

the lug is steal. the tubes are aluminum.

Update: Got it out.

used the hack saw method. Simple. I wish i would have done that a week ago. Nothing to it.

Here is the run down.

1. lop the seat post so you have about 1 inch sticking out.......(in my case that is where i broke it off trying to free it)
2. get a fine tooth hacksaw blade and duck tape it to a paint stir stick for a handle :)
3. stick it down there and get sawing. I tried to keep the blade as flat as possible on the length of the post vertically as i sawed. It only took about 30 minutes.
4. Once you get close to where you think the frame is.....stop
5. start another cut about a pencil width away from your frist one. Again cut to the frame or damn close and stop.
6. now you can take a break. Come back to it and carefully and lightly run the saw blade up and down a few more times in each slit and again...stop
7. Put a flat blade screwdriver in your exposed seat post and twist back and forth. The long narrow piece will snap off and fall down to the BB

At this point i had a long narrow chuck cut out but that sucker still would not move. No problem......I tried crushing it in on itself and twisting. Nope....the visegrip cracked the post all to hell after many attempts. I could not believe it.

at this point i thought.....what the hell.....and started doing the same process on the other side of the post....

I cut another notch out and it fell into the BB. At ths point the 2 remaining halves came out with the same twist of the screw driver.

Problem solved.

I went down in there with a small wire brush and cleaned up the inside of the tube real good where it was corroded and it is good as new.

simple process really. Glad i opted to try it. All the forum posts i read sounded like it was world war III trying to cut one out but it was very simple.

I can see if you had a steel one. That would be HARD to do.....very hard. Alloy was so soft and if you are careful and dont rush....its simple.

2 beers....some good tunes ......made for a productive saturday :)

thank you all for the help and suggestions!

Just for accuracy and completeness, I'll mention that thermal expansion of materials is not a matter of being faster or slower, but more or less. The speed at which it occurs depends on the speed at which you change the temperature of the material. For example, it's common practice to remove a stuck steel nut on a steel stud by heating the nut with a torch. The nut and stud both have the same coefficient of thermal expansion, but the nut gets hot much faster than the stud. The resulting differences in thermal expansion help break bonds that have formed between the two making it easier to remove.

Here's a question for you. If you uniformly heat a part with a hole in it (like a nut for instance), does the hole get bigger or smaller?