Best drill bit for 14 gauge stainless?

[Frank]

I need to drill several holes through some 14 gauge stainless and so far I have ruined 2 drill bits. I cannot use a drill press as it is on a car. What is the best kind of drill bit to use and how to be most effective? These are about 7/64th size.

[TENGRAM]

I would probably use my stepped drill bit for that. Not sure it would be the best choice but it would get it done and wouldn't break.

[projectPONY]

I've never drilled into stainless but in steel of that gauge I always use cutting oil. Helps with the life of the bit considerably.

[redfiveohconv]

Cutting oil is best , Motor Oil, Trans fluid, or even WD-40 will help. A slow drip or spray every few seconds. This keeps the chips from binding and catching on the flutes and destroying your bits.

Slow your RPMs down, you prolly burning that shit up. Stabilize your workpiece if doing it by hand and use a center punch or similar to start you off.

Locally and affordably you probably want to go with a high speed steel with a coating like AlTiN, the stor packaging will probably read HSS ALTIN or something. If you can find a Cobalt (Not the brand name, but the actual material prolly gold colored) drill bit, this would probably be the best bang for the buck. If you just want to spend the extra and its available go with SOLID CARBIDE.

[turbostang]

You will NEVER make solid carbide work for very long in a hand drill application. You will chip it or even break it in short order - your hands and a hand drill just isn't rigid enough to keep the vibration from killing it. Not to mention, you can't spin them fast enough in a hand drill - and if you could, see the first statement.


Cobalt is probably your best bet when drilling stainless by hand. SLOW it WAY down and push hard. When you over-speed the drill, you will work harden the material VERY fast, and therfor burn the corners of your drill.

Cutting oil is best.

[Doug Hatton]

Slow, lots of pressure and cutting oil works best. And be sure and breath in those tasty fumes that come off the bit! LOL!

[holeshot]

Plasma cutter ! Blow a freekin hole through it ! LOL.

[Doug Hatton]

I would also mention that, depending on the size of the hole, you'll want to drill a pilot hole, and maybe even step up in size several times until you meet the size hole you want. It's just much easier on the bit doing it this way.

[RuStYpNuS]

agreed with cobalt and cutting oil/ coolant. Carbide has to be tightly secured i.e. mill is its so hard that any vibration in the cutter/part would cause it chip and break. and Carbide isnt really cheap