BB and stripped threads question

just got a new frame and have come across a little niggle, the threads on the non drive side cranks are bolloxed so I cant use a crank puller on them. Any suggestions on how to remove the crank. I might see if I can remove the bb and crank arm with the crank still on the spindle and just scrap them both ?

also does anyone have any idea what thread a carlton flyer bb would take, its from the mid seventies I believe ?

Says nowt

If it's a cheap crank, just saw it off, or possibly try a two or three jaw gear puller? I have seen an over size re-threading tool for cranks, no idea where to get one??? Calling MDCXQ tester ??? He knows everything...

Here are a couple of bodges I have used before:-
how is the crank held on? a nut or a bolt?
If a bolt get an allen key one and screw it in to the axle, then get a self extractor ( a washer that is common on modern ish cranks, hollowtech 2 for example but there are others, your LBS probably have some knocking about the workshop) which should screw in to the threads (but not securely if the threads have gone, you just need to get it into place).

Then get some metal epoxy, I got some really fast setting stuff from B&Q for about £4, and use that to secure the self extractor. If the threads are really toast and you have access to a drill drill a couple of holes into the crank so that you and screw in a couple of self tapping screws to hold the self extractor before using the epoxy. The crank will be toast now!

Make sure it is all free of oil and grease, and you can still get the allen key into the bolt.

Then leave the bike a while, preferably outside, so it goes cold, and the epoxy has set rock solid .
Now pour boiling water over the crank and immediately unscrew the bolt with an (8mm) allen key. This will pull the crank off.

Sounds complicated but it isn't really, and it works pretty well.

If the crank is held on with a nut and you have an old pre cartridge bottom bracket then remove the drive side crank and the drive side BB cup. The axle will now be loose in the frame. Loosen the nut on the non drive side axle a couple of turns, put a socket (usually 14mm) on it and with the frame suitably supported hammer the socket to push the axle through the crank. Pouring hot water on helps here too.

If the crank is held on with a nut and you have an old pre cartridge bottom bracket then remove the drive side crank and the drive side BB cup. The axle will now be loose in the frame. Loosen the nut on the non drive side axle a couple of turns, put a socket (usually 14mm) on it and with the frame suitably supported hammer the socket to push the axle through the crank. Pouring hot water on helps here too.

nice one sound good, will defo give it a shot.

I had a similar problem, and am feeling pleased with myself for solving it, so thought i'd share. I too faced stripped non-drive side extractor thread, but with a miche sealed bb (detachable cups on both ends):

Remove the non-stripped DS crank, and the NDS crank bolt.
Pack the gap between the stripped crank and its bb cup with stuff - one of those cheap pressed steel multi-spanners worked for me, but one or more large cone spanners would probably work too.
Unscrew the DS cup about a third of the way.
Replace the DS crank. It should hit the DS cup while still loose on the taper: you may need to add more packing to make it loose enough.
Replace the DS crank bolt and tighten it to pull the axle out of the other crank.

Worked for me.

It may be better to remove the drive side bb cup if you have something suitable to hold the crank away from the frame, rather than applying all the force to the drive-side cup threads.

This should work fine with old non-cartridge, 2-cup bbs, and obviously will work the other way round if it's the drive side extractor threads that are stripped. For Shimano style 1-cup sealed bbs this is obviously useless for stripped drive side threads, but a variation might work for stripped non-drive side threads:

Remove the non-stripped DS crank, and the NDS crank bolt.
Unscrew the bb from the DS as far as you can, clean up and grease these threads, screw in and out a few times to work the grease in as far as you can - you're about to ask a lot of these threads, so you want them as well lubed as possible.
Screw the bb back in.
Pack the gap between the frame and the NDS crank.
Unscrew the bb from the DS to pull the axle out of the crank.

This method places the force on the DS bb threads and the bb bearings. You might be able to relieve the force on the bearing - i think a crank bolt through the middle of a cassette tool jammed into the middle of the Shimano bb tool might apply the pull directly to the axle, but that forces the axle to turn as you unscrew and still leaves the force on the DS bb threads.

The big risk with this method is that you wreck your bb shell threads and write off your frame. Probably more of a risk with aluminium frames than the steel one i was working on.