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I read a few online articles on drilling into metals. The advice is mostly the same:

  • Predrill a smaller hole.
  • Drill slowly — low rpm.
  • No need for fancy equipment — any drill bit specialized for metal will do.

My problem is that I can make holes into some metals but not others. Should I add pressure? I learned that when I lean into the drill with my entire body, it helps somewhat, but the Hephaestus is surely frowning on me.

Martin Drozdik
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  • Your question is rather vague. "Metal" is a vast range of things, and common bits simply won't drill some of them. – isherwood Jan 11 '22 at 17:46
  • You need a drill bit that is harder than the metal. You will need to exert consistent pressure, but not to overstress which tends to break the drill. The last thing you need is the patient. – r13 Jan 11 '22 at 18:19
  • Use a bit appropriate to the material being drilled. Based on the vague information given, that's about as specific an answer as you're going to get. – FreeMan Jan 11 '22 at 19:33
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    They are wrong. There is one correct "feed and speed", google that. Drill-drivers are stupidly too slow by orders of magnitude. "Drilling" results in instant efficient cuts with a cool running bit.m and long chips. Anything else is *"not drilling"* and will only work-harden the metal, making it tougher to get cutting again. Stop instantly if "not drilling"! – Harper - Reinstate Monica Jan 12 '22 at 00:45
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    Are you drilling *stainless* steel because that can be more prone to work hardening than mild (as well as harder to start with). So stainless can end up harder than your drill bit – Chris H Jan 12 '22 at 11:48

1 Answers1

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As noted in the comments, "metal" is a very ambiguous term here. Some metals are very soft and easy to drill. For example Aluminum or copper. Others are harder, like mild steel. Others are very hard and quite difficult to drill, such as hardened steel. Additionally there are other metals that are virtually impossible to drill with a mechanical drill bit, say tungsten.

You need to determine what it is you are drilling and use the appropriate tool. For most common things you want to drill a standard "high speed steel" bit should do the job. For harder materials you may need to use a tungsten-carbide tipped bit.

In any case you should use care to avoid forcing the drill, use an appropriate speed, and in many cases use a cooling fluid.

jwh20
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