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@JoeWe1313
Has anyone else had trouble with plastic bottom brackets?
I just managed to get one out of my Giant Cadex and it was torture!
I thought I'd post how I did it in case anyone else has this same problem. However, It's by no means a pretty solution so if you do decide to give this awful method a go, last resort only.
Here's the issue:
The crappy little plastic bottom bracket fuses COMPLETELY to the thread.
Because the bottom bracket and locking are plastic, the method of tapping it round with a hammer and screwdriver is USELESS because the thing just disintegrates and you end up with a round nub thats impossible to get any purchase on.
The stages I went through included every type of gripping tool, new lockring remover, gallons of wd40 and screwdriver/ hammer combo. (at this point I thought I'd never get the thing out).
Eventually i got so pissed off that i smashed the spindle through the sealed bb and out the other side with a sledgehammer. To my surprise the spindle flew out the frame and thus new angles of attack were opened up to me.
there was only really one thing I could do and that was to thread a hacksaw blade through the tube and onto the saw at the other end and try and saw through the bb shell.
Previously I'd thought it was just the lock rings that were plastic but it turns out the whole damn thing was.
Unfortunately there was a hardened steel washer or something embedded in the plastic shell and i couldn't saw it so i had to somehow get it out.
After desperately trying to drill the plastic away from the washer i decided to fix it once and for all and blowtorch the damn thing to freedom, but i didn't have a blowtorch so i used a heat gun.
heated the plastic up to 600 degrees setting off the fire alarm multiple times and chiseled the ring out
it was then reasonably straight forward to saw a chunk out of the plastic and push the rest free.
So I was finally left with nothing but a thread in the bottom bracket tube and likely a somewhat weakened carbon fibre frame.
All I can say is I hope the fool who decided a plastic bottom bracket was a good idea has to go through the same ordeal
(ps. I did try and unscrew the thing the right way)
will try and upload some more pictures of the aftermath and equipment when i get home.
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