I noticed some play in my frame, and to cut a long story short, tightened the bolt that it was coming from and stripped the threads out of the lug on the seat tube.
It’s this bit where the swing arm linkage bolts onto the seat tube, just behind the top shock bolt:

there’s been play in it before, and I tightened that one up (it was quite loose then) and it cured it. Not sure why it came loose though…

anyhow it wasn’t loose this time, so I took it off to check the bushing and get a photo of it, in case it might be that being worn that was causing it and to get a pic of it, and then put it back – and as i was tightening it, pretty tight but not uber-torque or anything, it ‘went loose’, and wouldn’t get tighter, and then unscrewing it wouldn’t bring it out – that’s when i knew the thread was buggered…

I’d contact the manufacturer but the manufacturer of the frame is canyon which is in germany and they don’t speak very good english or respond to emails so it’s a bit of an arse… I thought it might be possible to get a frame builder in this country to make a new bit the same as the bit that contains the threads, cut some threads into it and weld it on – but am I right in thinking you can’t after-the-fact weld aluminium?

so is this the death of my frame?

helicoil

hmm, i wouldn’t worry about chopping things off and re-welding bits onto the frame. my suggestion for a stripped thread would be to get it machined out and a heli-coil fitted to it, although it could be possible to weld a new lug on if required. local engineering firm should be able to help (or someone like argos cycles if requiring something more specialist)

how would i go about getting one of them installed then?

ah ok brilliant, so i basically just need to get some kind of steel fabrication dudes and show them the bolt and the hole and get them to do it?

yeah basically. that bolt will be like an M6 or whatever, they will machine that lug out to 6.5mm or something and fit a helicoil into it. they look liek this:

http://www.emhart.com/products/helicoil.asp

ok, so what sort of engineering company do I need to look for?
there’s loads of different types of engineers…

and also, why would it have had play in it in the first place do you think? it’s definitely from there, and the thing that looks like a bushing (metal-rubber-metal disk in the swing arm) looks fine.
Not tight enough (even though it was tight?) and will a helicoil enable me to get it pretty tight?

the helicoils are ridiculously strong, often used in Aerospace industries. as for who you can get one fitted by locally, i can’t really help.

ok cheers, i think helicoils and your telling me of them may save my frame’s life!:-)

having looked at the Yell link, i would probably start with “precision engineering”

http://www.yell.com/ucs/UcsSearchAction.do?scrambleSeed=13070224&keywords=engineering&companyName=&location=Lincoln&searchType=advance&broaderLocation=&clarifyIndex=9&ssm=0&ooa=&M=0&rad=&lCOption32=Engineering+Machine+Shops%3AMechanical+Engineers%3APrecision+Engineers

try them 3 and see how you go

they’re the fellas ! cheers for that 🙂

What about a tap and die set? You use this to re-thread what is there using a slighly bigger bolt

holy thread resurrection batman!

Tyredocter – Member
What about a tap and die set? You use this to re-thread what is there using a slighly bigger bolt

I think he may have it sorted by now 😆