Seriously stuck plastic bottom bracket!

carl1983
carl1983 Posts: 162
edited August 2014 in Workshop
Hi, I have a plastic bottom bracket stuck in the frame on my 1982 Raleigh TI, Both the drive side and none drive are plastic, I managed to get the non drive side cup off but struggled all afternoon with the other! It is so bad now all the outer plasic is sheared off and I have been hitting a thin screwdriver into it to try break it out! I have only managed to create a hole on the top of the bottom bracket going right through but its so much work and I'm really worried I will dammage the frames thread if I havn't already! Any sugestions? I can only think of heat now.

Comments

  • earthvspace4XTuUWcX
    earthvspace4XTuUWcX Posts: 322
    Use a hack saw blade to cut through the plastic cup down to the threads in 2 or more places (you can tell when you reach the theads as the sound will change, as long as you are careful it was cause any significant damage to the treads) it should then be easier to break it out with your screwdriver.
  • Monty Dog
    Monty Dog Posts: 20,614
    Bike shop technique: Out of the view of owner, 4lb club hammer and smash it out! (Not suitable for carbon)
    Make mine an Italian, with Campagnolo on the side..
  • carl1983
    carl1983 Posts: 162
    xdoc wrote:
    Use a hack saw blade to cut through the plastic cup down to the threads in 2 or more places (you can tell when you reach the theads as the sound will change, as long as you are careful it was cause any significant damage to the treads) it should then be easier to break it out with your screwdriver.

    The trouble is the bottom bracket is still in there with it as its the drive side.
  • carl1983
    carl1983 Posts: 162
    I've tried wacking the square taper from the other side but it's not moved even a mm! I made a small hole through the threads with a very thin screwdriver but thats as far as I got because I'm worried I may have slightly warped the bottom bracket with the pressure!
  • earthvspace4XTuUWcX
    earthvspace4XTuUWcX Posts: 322
    carl1983 wrote:
    xdoc wrote:
    Use a hack saw blade to cut through the plastic cup down to the threads in 2 or more places (you can tell when you reach the theads as the sound will change, as long as you are careful it was cause any significant damage to the treads) it should then be easier to break it out with your screwdriver.

    The trouble is the bottom bracket is still in there with it as its the drive side.

    Ah sorry, assumed you had been able to remove the axle,
  • carl1983
    carl1983 Posts: 162
    photo7.jpg

    Here's my nightmare!
  • Ouija
    Ouija Posts: 1,386
    Melt it....

    Heat up the axle and bearing casing until the plastic around it softens and then tap the other side of the axle.

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