Interesting problem
I'll probably try it in conjunction with the cutting a slot into the drill bit.
The big challenge will be starting to grind on centre of the drill bits core. And if you slip off centre and snap off the diamond bit, your really screwed. All the more reason to get a pilot guide rigged up for the diamond cutter.
I would not drill beside it and use a easyout. If you snap that in there, then your dealing with a very hard material that's harder than the drill bit. You should also use extreme caution when trying to move the drill bit with a ***** punch and the like, you don't need to ad to the hardend metal that's already in the hole. I don't know if it has been mentioned yet, but in case it hasn't, don't try to drill with a carbide bit. Those things are harder than the gates of hell, and very brittal, and break very easy.
You didn't say if the drill bit jammed when it snapped?
If it did, its usually tough to get it to move. If it just snapped off , then you can assume the bit is very hard and brittle, and pounding on it with a punch will many times break it up enough to remove it.
You also might do a search on dissolving a drill bit chemicaly. I have heard of this,but never tried it. But it does take days to happen. Being your working with a broken bolt/ bit that is vertical it maybe a option for you. In the end you will probably end up with a nut sert/ time sert or at least a heli-coil once the offending bits are removed.
Another way I have removed broken bolts is to hold a nut over the broken bolt with needle nose and mig weld in the centre of the nut then back it out after it cools.
A standard drill bit cane be removed, but remember if you snap a carbide bit in there,it will be a real bitch to get that out. Diamond bit is just as bad , but you want to use it to grind the drill bit away. Hope this gives you some ideas.
Any chance ya can get a pic on here of what your dealing with ?
WP
Ok another ? Are the threads recessed into the frame or are in a boss ( my term) attached on top of the frame ?
I don't think I can drive it through.
That is something else I am thinking about.
That is a last resort for me as I'd rather put a bolt in it but if I have to then I will.
You might try a simple test first.
The remainder of the bit that broke, I would mount in a vise and with a sharp hit with a hammer. if it is carbide it will break again. The standard el-cheap-o bit would tend to bend instead. It would give you a better idea of what your dealing with.
One last thought for you.
Over the years many customers have brought in many things with broken bolts, drill bits,and taps stuck in blind holes. When I know for sure its very brittle, I have had good success breaking up taps with a air hammer. A drill bit would be tougher because the point is supporting the piece un like a tap.
Carbide breaks up pretty easy. You would need to grind or machine the tip to the proper diameter of slighty less than a 1/4 inch.
Last edited by 8ntsane; Oct 26, 2014 at 06:47 PM.
The Best of Harley-Davidson for Lifelong Riders
You might try a simple test first.
The remainder of the bit that broke, I would mount in a vise and with a sharp hit with a hammer. if it is carbide it will break again. The standard el-cheap-o bit would tend to bend instead. It would give you a better idea of what your dealing with.
One last thought for you.
Over the years many customers have brought in many things with broken bolts, drill bits,and taps stuck in blind holes. When I know for sure its very brittle, I have had good success breaking up taps with a air hammer. A drill bit would be tougher because the point is supporting the piece un like a tap.
Carbide breaks up pretty easy. You would need to grind or machine the tip to the proper diameter of slighty less than a 1/4 inch.
Thanks for the tips.
If D gyvers idea doesn't work I'll try that.
To me welding the bracket would be giving up and I hate to give up on something.
Granted it is a perfectly acceptable answer to the problem.
I like a plan of drilling small holes next to the broken carbide bit and see if it will work loose, drilling or grinding carbide is a MF. If you go into the threads with this plan, nothing wrong with a heli coil when done right.
Have blown out broken bolts, drill bits with a plasma cutter and the catazz but not a common tool in the home garage. Welding a nut on it may work and they make a special rod for a stick welder to do it and gotta have some big ***** to weld it on a Harley











