Snapped seatpost

drkawaszelong
drkawaszelong Posts: 260
edited July 2011 in Workshop
Hi guys, recently bought a frame on here, seatpost snapped inside....how should i remove it?

i tried eroding it away with caustic soda, which has done nout but make it shiny.

12072011170.jpg

next, i drilled a hole into the back of the seat tube (where you'd take the height reading for the post), threaded some wire through, and tried to yank the post out, still no success.

12072011172.jpg

so, what should i do now?

there's also a little dent on the top tube, the size of a little finger nail, how should i cover that up/repair it?

i'll give y'all 2 weeks to think of something, as i'm away. haha. see you then

thanks in advanced!

Comments

  • Monty Dog
    Monty Dog Posts: 20,614
    Heavy tool: Drill it out progressively and then run a reamer down.
    Make mine an Italian, with Campagnolo on the side..
  • brucey72
    brucey72 Posts: 1,086
    You could try a reciprocating saw to cut a slit in the side opposite where you have drilled the hole. This might allow the seatpost to be lifted out by the method you mentioned. You would just need to saw gradually to ensure that you weren't sawing through the frame as well.
  • bill57
    bill57 Posts: 454
    You bought it like that? Hell Mend you.

    In the past I've cut one out with a hacksaw blade, hards work and I carelessly cut into the seat tube. On another one I used progressive seat tube reamers at my LBS, that was even harder work but did the job without damaging the tube. Unfortunately as the reamers are tapered, it wouldn't go deep enough but I got enough out for a secure fitting of a new post.
    The method I would try first, but will depend how seized the post is, would be a slide hammer.
  • Mr basset
    Mr basset Posts: 5
    If it's a really good frame, and you don't want to muller it, take it to Argos Cycles (in Bristol) and they'll sort it. Not cheap, but technically brilliant and good with the paint jobs too.

    If its an average frame, try one of the DIY engineering jobs above.

    If it's a crap frame, I'd be tempted to return it to the owner via his a**.
  • bill57 wrote:
    You bought it like that? Hell Mend you.

    bought purely (regardless of condition) because it was originally from a shop that is literally a 5 minute walk away - a bit of local love :) , and besides, i've got loads of time to work on this.

    thanks for all the suggestions, will try them out when i get back

    reaming sounds quite a common idea.

    keep 'em coming.
  • Arghyrou
    Arghyrou Posts: 155
    I had an old peugeot which I stuck a dead cheap carbon seat post in, a month later it was jammed and couldn't get it out. Didn't really want to cut it so used the old fashioned coke, (which I think helped) then ammonia, (miracle worker) slid out straight away. Had to leave it overnight to penetrate though? Worth a try? Good luck
  • Arghyrou wrote:
    I had an old peugeot which I stuck a dead cheap carbon seat post in, a month later it was jammed and couldn't get it out. Didn't really want to cut it so used the old fashioned coke, (which I think helped) then ammonia, (miracle worker) slid out straight away. Had to leave it overnight to penetrate though? Worth a try? Good luck

    coke? as in coca cola? or coke as in pure carbon (C12)?

    and where am i going to get ammonia from? Haber it? :) sounds good though. more info please!!!

    and how will i stop it from leaking out the bottom?
  • Yossie
    Yossie Posts: 2,600
    I know it sounds silly, but do you have to take the seat post out of the frame: ie is it an alright frame that you really like the look of and want to run something retro and funky with (eg inner city single speed runner) and are not worried about the weight, or is it a really good frame and you are building it up really trick?

    I'm only thinking that because if its the former why not just smack the snapped seat post further down the seat tube than it is to enable you to put a new seat post in - easier than getting it out and no one will ever know ........... Cold chisel or rubbish ali/steel post of exact same size will do the job. Steel preferably as it won't collapse as you smack it. Avaialble from local scrapyard for nowt.

    Ok, not the best way of doing it and you will have, oooh a couple of hundred grammes of extra weight in there, but if it gets you on the road.......

    If you going to try and get it out, remember to heat the outer part of the frame (heat gun won't damage the paintwork like a blowtorch), spray loads penetrating fluid/duck oil down there (do it repeatedly over a few days - two or three applications a day to let it seep in) then try the methods above.

    Remember to tap the frame with a toffee hammer as you spray in as it will help the fluid penetrate. Tap, not smack mind you ......

    Also spray in from below (ie BB area) if poss.
  • keef66
    keef66 Posts: 13,123
    Squinting at the blurry upper photo It looks to me as if there's a shim between the post and the tube. That should help prevent you cutting in to the frame. Fine blade in a reciprocating saw, or a hacksaw blade and a lot of patience. Once you have a full depth cut in the seatpost, stick something in the hole you've drilled and tap it upwards.

    If that doesn't move it, try to hammer something between the tube and post to one side of the cut; you need to make the post curl in on itself like a swiss roll