drill bits; whats the 'hardest'?

[Guest Anonymous]

In order to drill out that nasty stud extractor..whats the 'hardest' material I can get? Hardest at my local hardware place is titantium (or titanium coated at least). Are carbide bits harder?

thx

matt

[Guest Anonymous]

they are very expensive, but that's the only thing that might work, get a 1/8 inch diameter and the trick is not to over rev your drill, slow speed and pressure is will do the job, spray oil wd-40 or similar to keep it from overheating. Get a screw stractor and jam it in the whole with a hammer, if this does not work, go a size bigger with both drill bit and screw stractor, good luck!

[Guest Anonymous]

Uh, actually slow speed will bust a carbide bit. They are way hard, but brittle and do not like to bite off big chunks (i.e. low speed and heavy pressure).

My advise:

1. Put a small stone in a dremel and grind a flat spot onto the top of what is left of the extractor. This will help start the drill.

2. Get several carbide drills, stepped in size. Start at 3/32 or 1/8 and step up to a size just inside the Minor diameter of the extractor.

3. Using lots of WD as coolant, use high speed (your fastest drill motor) and only enough pressure to keep making chips. BE PATIENT. Carbide drills are brittle so use as little length protruding from the drill motor as possible and have a steady hand.

Since the extractor is reverse threaded, it may back out when you get deep enough with one of the larger drill sizes.

Hope so anyway. Next stop: EDM.

'72 tii DSPish (soon for sale by the way)

'79 R100RS