no expert on this.
I'll just say that I bought an expensive set of nitride (?) coated ones, and I've chipped several already. Typically from getting the bit stuck when enlarging holes. Poor use I guess. But likely that means that the harder the bits the more likely they are to shatter - unsurprisingly. So a compromise may be in order.
Anyway, I did get a bit sharpener machine and I must say it is worth the $$. I was able to resurrect a ton of old bits, and conceivably one could make do with less expensive bits if you can sharpen then easily.
Cobalt bits last the longest in metal. I bought a metal index box at harbor Freight, and as I break or dull them, I replace with USA made in the same size. Probably have about 1/2 good bits now.
The trick to keeping them sharp is to use cutting oil and lots of it. Do as much of your drilling that you can in the drill press. You break many fewer bits that way.
I try and always start a large hole with a small cheap bit, like 1/8 inch. That seems much easier on the bigger expensive bits and helps to keep them sharp.
Also, I have found that step bits are almost indespensible.
btw, I had played a bit with sharpening bits on a grinder and sure enough it works but for my level of skill at least it isn't close to as good as I can do with the sharpener. Which also does self-centering dual points. But anyway, in a pinch you do a pass or 2 on the grinder and it may allow you to continue the job at hand.
e9999, have you tried sharpening those coated bits? I chipped one up, and tried to sharpen it in the Drill Doctor, but it wouldn't take an edge. Regular high-speed steel bits sharpen up nicely. I'm coming to the conclusion that the coated bits aren't for me.
e9999, have you tried sharpening those coated bits? I chipped one up, and tried to sharpen it in the Drill Doctor, but it wouldn't take an edge. Regular high-speed steel bits sharpen up nicely. I'm coming to the conclusion that the coated bits aren't for me.
my bits are made by Huot (well, at least the box is). Gold colored. I think they are Ti-nitride coated but not positive. Anyway, they do sharpen just fine on my Drill Doctor ( a 500 from memory).
I will say though that I'm having less than perfect results with the split point sharpening. Not always fully symmetric. But not just on the nitride bits. Maybe lack of practice.
