A masonry bit will work- it is carbide. I've even sharpened them for cutting metal. The method 70blue describes uses the heat generated to soften the metal. We used to cut stainless on a bandsaw that way. It was a special blade, run pretty fast. You push the metal against it hard. At first, nothing happens, but once it gets hot (really hot, wear gloves!) it goes right through. You need to run at a much higher RPM and a lot of pressure for it to work.

 

I have had to use carbide bits to drill into work hardened stainless steel. The only draw back is that carbide is more brittle and is not forgiving like high speed steel. I have broken several. Slow down and use a lot of cutting fluid or coolant.

 

For sheer cutting power I use cobalt tipped bits over Titanium. Blows right through steel rivets on my trucks suspensions mounts. Keep them oiled and go slow because they will burn up otherwise

 

When all else fails use a carbide masonry bit. The hole wont be pretty but it will usually do the job.

 

I always sharpen my bits by hand using a bench grinder. once you get good at it and get your angles right i find they actually cut better than when they were brand new.

 

My daughter gave me a set for Father's day. I love 'em. The hex base is a nice design as they don't spin in a chuck with worn jaws and they also pop right into my Bosch 10V lithium driver which accepts hex base bits and tips.

Reg

 

I find that hard to believe unless you changed the angle to match the hardness of the material your drilling then I can believe your statement and it would be correct.

 

I do this all the time, and I make my relief angles a bit sharp in most cases because the bit cuts much faster and with less effort except in very hard material. The "standard" relief angles are for harder materials. I have to sharpen more often than with the standard relief angles but find the faster cutting makes it worthwhile. The most difficult part of sharpening by hand is to get both sides exactly symetrical. Otherwise, one side ends up doing all the work and the hole will come out slightly oversized.

 

I have tried several different sharpening devices that arent worth the material they are made of. I learned to sharpen bits by hand from an old school machinist. I will put one of my hand sharpened bits up against any new bit or one sharpened by a device. The only way to get good at sharpening a bit by hand is to practice it over and over again until you get it right. Once you learn the technique you can sharpen just about any regular bit easily. I dont normally mess with sharpening any thing less than about a 5/16, it get to small to handle and they are cheap enough not to have to worry about it.

 

This is the way I learned to sharpen bits by hand. I had posted it in another post on drill bits, I copied and pasted it here. Now this is the way I learned and I know there is other equally good methods out there. this one just happens to work for me.

If you are sharpening by hand and your grinder has a rest on it, support the bit with with your index and middle finger. Hold the bit with the cutting edge turned up and paralell to the stone. Start grinding on the bottom of the angle up to the cutting edge until you see the first spark break the cuttting edge . Stop at that point, if you continue until you see sparks all the way across the cutting edge you have rolled the cutting edge over and rounded it off ( most common mistake in hand sharpening). Use a lifting motion not a twisting motion. Remember to constantly dip the end of the bit in some type of coolant every few strokes. With the cutting edge turned up and paralell to the stone you have the correct angle, if your bit was correct to begin with. You can scribe or draw a line on your rest at 64 degrees and eyeball off the line, that will give you 124 degrees total end angle. When done sharpning you should be able to look at the end of the bit, while holding the bit so the cutting surfaces are flat, the web in the center should be at about 45 degrees to the cutting edges. Also the cutting edges should be equal in length. If your bit has more cutting edge on one side you need to take a little more off the short side to even it up. Starrett makes a gauge that is at the correct angle and is marked off in 1/16 inch intervals to measure by. This is how I learned to sharpen bits. You can talk to different machinists and get a different way from each one of them. If you dont have a way to practice this technique or any other hand sharpening technique and get comfortable with it you will probably cause your self more drill bit headaches. I would recomend investing in a drill doctor unless you can practice it and get good at it.

 

Good post bhardy, I would just add that the finer the wheel, the more heat it builds. And the faster the grinder, the more heat is generated. Overheating, which you will notice by discoloration, ruins the bits. So quench frequently.

 

When your out of practice you'll end up with short bits trust me.

 

Its like riding a bicycle you never forget. I learned 20+ years ago and about 3 years ago I decided to finish up the machine shop program. I had not attempted to sharpen a bit in quite a few years. I picked up the first one and sharpened it with no problem. It didnt take more than just the first few strokes on the grinding wheel to have the feel of it back.

 

That's what my girlfriend said!

 

Ashes to ashes, dust to dust without our women our drill bits would rust.
I kill me sometimes.