Hi.

Can the drill bits used for masonry, -the ones with widia tips- be sharpened at a different angle or shape for use in drilling steel ?

 

How does it work ? Is there optimal angles (chart) for different alloys as hardened steel, iron, stainless, bronze, aluminium... ; and has a chosen angle or shape also a preferred optimal cutting speed (chart) for each metal ?

 

Once I saw a demonstration of the same drill bit used in porcelain, steel, cast iron, stainless, concrete, brass, pvc and performing equally well on any ¿?. It had a widia tip insert.

Thanks.

Widia is just a term for cemented carbide so sharpen as you would any carbide tool. I wouldn't try changing the angle as you lose a lot of material and the cemented tip is relatively small to begin with. Check online or otherwise consult the manufacturer for recommended material applications.

 

Drilling speed is based not only on material being drilled, but the diameter of the bit. Here's a page with some guidelines. >> http://store.curiousinventor.com/guides/drill_speed

Different materials would require different angles, but

- It's a matter of optimization, not of mere feasibility

- High-speed steel offers this flexibility. Carbides are even more brittle, so sharp tips are difficult

- Beyond tool life length and part's surface finish, the tool also defines how the chip breaks (if it does!), which is very useful.

 

I did use once a concrete drill bit in glass. I sharpened it with a grinding wheel, and operated fully under water. The glass was a Champagne bottle, for high-quality de-stressed glas. It worked nicely and faster than expected, with the tool producing a thin chip, not just dust as I thought. The hole was a clean cylinder except at the exit.

 

Are the usual concrete drill bits of the same material as the carbide ones for metal? No idea. The requirements differ, because concrete is usually drilled using shocks.