Drilling out BBS alloys snapped bolts

[Kbald]

As the title suggests I've managed to snap 10 of the 20 bolts trying to split the alloys and round 1 head off so can't get this out. I kept going as was hoping when I split the rims I would have enough of the bolt showing to get some grips on them but with the final bolt had round I can't even split them.

Does anyone have any ideas what type of drill bits etc I'd need to do these what seem to be very hard bolts? Any tips and advice would be gratefully received.

 

[stuttgartmetal]

Have I read this right.
Only one bolt with a round head is holding the halves together ?

 

[Kbald]

Yeah that's correct. The wheel is obviously not on the car. I have a set I am refurnishing or was.

 

[kurlykris]

The bolts will be Titanium, a very tough material. High Speed Steel (HSS) drill bits will get through it if sharp, slow speed, not too much pressure and some cutting oil, the drill edge will dull quickly if you don`t take your time.
A Carbide drill or carbide coated bit would be better, again, plenty of cutting oil and take it slow.
I`m presuming the bolt is an allen key cap screw, so you don`t have to drill too deep to drill the head of it off :thumb:
I think I bought my set of carbide coated bits from Screwfix last time :grin:

 

[Jamie]

I'm assuming we're talking about the cap head BBS bolts, as the rounded bolt is knackered anyway, can you not just hammer in an oversize bit?

 

[Kbald]

Thanks all. I will try those bits and some cutting paste to see how I get on.

Jamie yeah I tried that but could get anything to grip in there and there's nothing left really now inside to grip onto