Ok, I thought you were using cobalt drill bits. Were the titanium coated bits drilling ok? One problem with them is, once the coating is off the tip, you lose the hard edge and sharpening them won't get it back. Carbides are still more brittle, but not as much as cobalt. Just don't try to force it to drill too fast, and get the left handed ones.

 

I must've typed wrong, I am using the cobalt steel bits and they are titanium coated. Looking at the bit once I removed it the titanium coating wasn't off, there wasn't really time for that to happen. I began drilling saw some material come out, dust like, and then the bit broke very quickly. A few pieces off the tip shattered.

I just need to make sure I get a good solid material bit that will hold up. Not sure what would be best now since I was almost positive what I had, the set that broke, was going to work.

 

After looking around that link you gave, the Carrera extractor set looks good but again not so sure. More advice on best set to get or material wise would be great. I've been looking and everything is a cobalt set and most reviews talk about them breaking.

 

I think you'll have better results with a full set like that, then you'll be able to step up one drill size at a time, taking just a shave with each drilling. I take it what you were using was a smaller bit to start with, then stepped up a number of sizes for the next drilling? Unfortunately, I don't see a description on those drill bits as to what kind of titanium they are made of. There are 3 different types, good better and best based on strength. Titanium Aluminum Nitride (TiAN) would be the preferred ones. I can't tell you that cobalt is the way to go, as you've already found out they can be brittle when snagged. Darn hardened bolts can be a real beech to deal with.

 

The starter hole and bit I used was 5/32" (not from the cobalt set) and then the next size up in the cobalt set I got was 1/4" so it was a slight jump. I've been looking on HF and they have quite a few different sets that are titanium nitride coated which is what you said would work best, but they don't appear to be LH bits. But even though the coating is tough, wouldn't the center core material matter more, or does the titanium coating make up for that?

http://www.harborfreight.com/29-piec...-set-5889.html
http://redmoonbay.com/cart.php?targe...roduct_id=3162

 

Still having problems, and once again still HOPING to get this solved this weekend. Have broken a few bits off while attempting to redrill and enlarge the hole through the bolt. I have reverse(LH) cobalt drill bits with titanium coating, the last bits which broke were cobalt with titanium as well yet neither of these say what type titanium like tin etc. So hopefully with some more cutting fluid, a torch, and the reverse bits I will be able to drill it out soon. Any other advice?

 

Jeez, you're still at it? Do you have (yet) a high speed dremel tool, with steel cutting bits? You might need to go carving at the bolt till you can work it down to a thin layer, then dig it it with a sharpened point drift and hammer.
One other thought I have, is to heat up the crank with a torch, and shove bits of dry ice into the hole you drilled, or will carve out bigger. Dry ice is -109.3°F, and if you can heat up the crank to say 200° as an example, that's a 300° spread. That might make the bolt shrink enough to rap it out with a punch and hammer.
Now, if that bolt is bottomed out real tight on the back side, you might be fighting an altogether different battle.

 

There's quite a bit of room on the backside, I may be bottomed out on the threads though but there is still a decent gap behind the bolt. I also thought about just taking a smaller bit and drilling a few holes and trying to break it up. Been out there a good handful of times and hasn't got better.

I have 2 drills (one with low/high setting as well as reverse for the LH bits) and I have a dremel tool. They make bits for the dremel that are strong enough to handle drilling into a metal bolt? The dremel would make it easier since I'm working with little room, but harder to keep steady or straight.

 

They make the bits, but I don't know how long your bolt is going to let it last.
Dremel Type Carbide Cutters | Carbide Cutting Burs - Dremel Type Cutters | Cutting Burs | High Speed

 

Those could probably do the trick, slow and steady with a little help from the cutting fluid for insurance. Just to eat away at the bolt a little at a time to pick it out, this has been a real hassle....oh the uses for a time machine!