Hit a bit of a snag for my new build

Bought a new 2x10 XT chainset, but can't get the inner ring off

The chainring bolts seem to be made of cheese, and strip/round off at the slightest bit of pressure (even with the correct tool bit)

Got the outer one off by drilling a couple out carefully, but what to do for the little ring? Shimano have assembled it so tight it beggars belief. Have stripped 3 out of the 4 bolts :(
The bolts go directly into the spider casting - even if I get busy with the drill (if I'm feeling really really brave) it would still leave the thread in the hole

Anyone know any cunning techniques to get them out?

Heat?

Heat?

Worth a go. There's a very good chance they're thread locked so heat should break the bond. I assume the head is fairly big? If it is, tap them round with a sharp centre punch (carefully).

If you can drill the head off the bolts, that will probably* release the pressure that's holding it tight. Worked for me in other situations. Once the head is off and the ring removed, the remaining bit of the bolt should unscrew by hand.

* if they've used thread lock, you might be a bit buggered.

Cool - will give heat a go before I get the drill back out
In terms of heat, I'm am I right in thinking more boiling kettle as opposed to blow lamp?

In terms of heat, I'm am I right in thinking more boiling kettle as opposed to blow lamp?

Kettle won't do it ... blowlamp or hot air gun called for.

Thanks for the pointers. Will give it a go

The one out of four that you have undone, once you cracked it loose, did it spin out easy, or was it tight all the way?
If it was just tight because it was done up tight, then drilling or grinding the head off should mean you can undo the remaining stub easily, although you may need a stud extractor.
If it was tight because it was thread locked, then you will almost certainly need a stud extractor.
I take it they are hollow steel bolts in to aluminium?
A blow lamp could be a bit risky, an oven might be safer. Heat the whole thing up and the aluminium will expand more than the steel.

I'd only use heat as a last resort, you could possibly discolour the cranks, or even knacker them.

Where are you based Mart? I've got a few different types of stud extractors & can do all the drilling. I should be able to sort it for you..

Managed to get the last undamaged bolt out ... just. After I got it turning it was stiff for a few turns so suspect it has threadlock on it but there was no residue on the thread when i looked closely
Im thinking if I'm drilling, Im still going to need a stud extractor to get the thread out. Not sure they are steel, it feels more like they are made of dairylea. Softest steel Ive ever encountered

Fettling will recommence later

Wotsits, a very kind offer, im based in Burton on Trent if thats close?.
Did we meet you in Ilkley on the TdF weekend? my memories a bit fuzzy

I'm half way inbetween Liverpool & Manchester. We did have a chat at Ilkley, i was with a mate of mine (she was/is preggers)..

I'd first soak them overnight with a bit of WD40 or Plugas, left in a way where gravity will help it get into the threads.. Stu's good advice of carefully tapping the bolt head with either a centre punch or v small chisel might do it. Otherwise sometimes you can knock-in a slightly bigger bit (deffo safety glasses needed). If it 'grips' well it may do the job, but if the bolts are made of cheese it'd be less likely..
If you can get it moving even just a bit, add a bit more wd40 & just rock it back & forth while keeping the thread filled with wd until it's loose enough to unscrew more easily.

Ians advice of drilling the bolt head off is what i'd try next, ideally done with the crank level in a pedestal drill.
You don't need to drill all the way through, just enough so that the metal is thin enough to prise the ring off without too much brute force..
Also ideally you need to drill right through the bolt before using a stud extractor..
It's not as complicated as it seems, the hardest part is drilling any holes straight..

Wotsits wrote:I'm half way inbetween Liverpool & Manchester. We did have a chat at Ilkley, i was with a mate of mine (she was/is preggers)..

Phew - Im not cracking up then

Into action this wk - will keep everyone updated on how it goes
If it doesnt go well you'll probably hear me swearing from here

If you get a stud extractor kit, if it's not included, make sure you get the correct size drill bit to go with the extractor you're going to use.

When you drill the bolts you can mark the depth you need to drill with the bolt you managed to get out & some electric tape on the drill bit..

Be careful with the extractors, they're normally hardened so can snap like a carrot & are then a right pain to get out if they're stuck..

Good luck!

Phew sorted Got me one of these extractors things

http://www.halfords.com/motoring/garage ... ractor-set

With the bolt being hollow, eventually sussed the right size and inserted.
Light tap with a hammer to seat and turn.
Dug into the soft metal loveley.
It took the leverage from a 9'' adjustable to get enough torque to get them moving!

Right tight gits they were, thread lock in them was working well!

Thanks for all the ideas and help guys. Before today I didn't even know these extractors existed.

On with the build :)

Good news Mart, & no drilling required!

Nice one. A bit late to the party, but for the next inevitable stuck bolt, I'd recommend an impact driver. They really impress me every time I use them!