Aarrgh!!!! Need To Vent!

[Craig B.]

Ever have a day like this?

5:30 Monday morning. You go out to the shop to work on knives before going to work. You cut and profile a piece of 440c into the shape you want this knife project to be. Then you start to drill your pin holes, 1/8".

One hole done, move to the next. Half way.......Drill bit turns cherry red

Put in the only other new 1/8" bit you have, move to next hole and start. Puff....... cherry red drill bit

Now I know for sure that the steel hadn't been properly annealed at the factory.

I have fixed this by taking a propane torch and turning the hole blue, drill a little, blue again, drill, etc. until I drill through. But this knife is not going to have a price tag worth all that trouble as it is going to a friend at cost.

What a great start to Monday Oh well, I feel better now that I've vented a little.

Hope your Monday goes better than mine has started!!!

[Ray Rogers]

Sounds like a classic Monday morning all right. But, I'm not sure the steel was the problem, after all, you got the first hole done OK. That 'cherry red' comment suggests that you are drilling at a very high speed. I know that's what is recommended by some sources but it has never worked for me. I find that it tends to soften drill bits so they lose their sharpness quickly, get hot and glow cherry red, and work harden the steel. All my drilling is done at 250 rpm no matter what material, thickness of material, or type of drill bit and always with a lubricant. Never had a problem this way as long as you start with a sharp drill (I like the cobalt drills).

If you ever do have a situation like that again, a solid carbid Hi-Roc drill will make short work of it. They are pricey but they will drill through a fully hardened blade very quickly .

Hope your next Monday is better......

[Jason Cutter]

I support everything that Ray has said. I'd go as far as to start no higher than 250rpm on 1/8th inch bits, and down to 80-90rpm on the 1/4inch bits. Mine is a really really cheap drill press but it has better torque at low speeds to do the larger drill holes as well. The onyl reason I ever use the 1500-2500rpm range is when drilling leather with a blunt 3/32inch drill bit so it purposefully gets hot and burnishes the hole, and when I chuck buffing wheels into the drill press. Cobalt carbide drill bits - winners !!

And lube everything with coolant. I literally flood everything on the worktable with WATER. I keep a spray bottle nearby all the time and adjust the nozzle so it shoots a stream right onto the spot I'm drilling. Yes, it rusts the worktable but I dry it between jobs. I put a large dish underneath the worktable to collect the water and debris. The water also stops hot metal chips from flying too far.

I also got told to use "nice" high speeds when I bought the drill press. I think its all a conspiracy designed to keep us buying new drill bits. . Jason.

[Craig B.]

I forgot until @ noon today that I had a 6 foot piece of 440c that I had troubles with when I bought it a few years ago. The same thing happened no matter what speed I tried on this particular piece of steel.

I also remember having a little of it left over that I put in the scrap bin. Wanna guess where I got this piece of steel from? Yep, the scrap bin.

Oh well. Got some more drill bits at work today. Will start all over tomorrow morning.

You would think after 14 years of this stuff I would learn to just throw away a bad piece of steel. But, I ain't learned yet........