Drill 1/16th inch hole through 8mm stainless steel rod?

I've done this kind of drilling before and nearly always break a bit - when breaking through the bottom side.

What did I do wrong?

Using ordinary tools, is that realistic?

Talking about an 8mm hole sideways through the rod (from one side to the other), not down the center of the rod.

Thanks.

I've been doing all that, Lloyd. Except for setting the depth-stop. I'll try that nest time.

What I finally did get to work fairly well was to insert the tube I was drilling inside the next size tube and drill both.

I still broke the bit. :( But the hole in the the actual part I was making survived.

Drilling these small holes in stainless is a trip.

Yeah. One of my old quotes, "aluminum will cut you, but steel will make you bleed"...

Depends on the "ordinary tools".

But generally speaking..yes it is.

Big problem with using a drill motor is getting the hole spotted. Use a punch and make a good dimple. Then dont let up on the pressure. A drill press would be best, with the rod held firmly in a vise mounted on the drill press table. And use lots of coolant and when you back out to clear the chips..go back in and dont fart around starting the cut again.

Gunner

IT worked, but I didn't set the depth-stop. So I'll do it the way you suggested next time.

I didn't have enough drill bits for that lesson. :)

John Doe fired this volley in news:klkuk2$rio$1 @dont-email.me:

Not only 'realistic', but easy-peasy. Lloyd

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

Didn't he say "stainless", Gunner?

Lloyd

Richard fired this volley in news:8radnfj3ILCAhePMnZ2dnUVZ snipped-for-privacy@earthlink.com:

This is not a job for a hand drill.

It's not so much the problem of holding the bit straight, but rather one of regulating the pressure and cut per tooth... which is difficult to do by hand with that small a bit and that material (although he didn't say _what_ stainless..)

Even one of those $29.95 "drill press stands" improves your likelihood of success, where the speed of feed must be controlled carefully.

As said before -- never let off on the pressure, except by rapidly retracting the bit. Never allow it to 'idle' on the bottom of the cut, or you'll work-harden the steel. Prick-punching will also work-harden it. That might not be a problem with a 1/4" bit, but with a 1/16" drill, you be hardening almost the entire cutting footprint of the drill.

LLoyd

Why not? Assuming that you have a drill press as with a hand held drill it might be a problem is your hands shake :-)

More seriously. Set the drill press for the proper cutting speed; center punch the work or otherwise make a starting "hole"; and feed just fast enough to cut a continuous chip.

Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

That sounds like an opportunity to acquire some more tools!

LLoyd

Oh, I know what you mean, Gunner. And with larger bits I can do just that.

But a 1/16" diameter bit through stainless tube? No, it just happens to quick. I guess it's because the flutes are so tiny?

Granted - most of the time - John. But with 1/16" diameter bits, well . . .

And use a good quality drill bit designed to cut metal, preferably a first-world-made cobalt steel stubby, not some POS jobber gold-plated or black soft steel turdlet drill from a kit (at least the latter won't snap, but they'll work harden the SS and go downhill from there).

I'd also put a drop of 3-in-1 or other oil on there, but others may disagree.

The important thing is to take seriously what others are saying about not being wimpy about the feed or letting the drill linger at the bottom to prevent work hardening.

It is, even with a hand drill, if you buy decent drill bits and learn how to use them. Based on your long history of disagreeing with people who try to help you that may take hands-on instruction.

That's because I just told it to you, Alvin.

You know it's true, though. :)

Another thanks

Yep, absolutely, using quality drills, and even better would be starting with one ground with a split point for the first thru-hole drill. These drills begin cutting immediately upon contact with the workpiece.. an ordinary grind has a center web that must displace metal before cutting begins, which may be too late for some alloys of stainless steel.

A good method of increasing the hole size when starting with a small pilot hole, is to choose a larger drill with a web about the same size as the existing/previous hole.

If one has family or friends working in the trades, they might have some cutting lubricant they could give away.. which saves going on a quest to find some, and buying a large amount compared to the few drops that are needed. Great stuff to have around though, for any metal cutting task.