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It's my dad's drill and it's a Bosch. I'm not sure about the model no. etc because the box is missing together with the manual. He's been using it to drill holes in wood to install doors and also walls to hang pictures. I'm not sure if it can drill through steel though provided that if I'm using a drill bit suitable for that purpose (I'm not sure if there's drill bit to drill steel also). The steel that I want to drill is not stainless steel. It's just a 2cm x 6cm rectangle hollow bar and the thickness of the steel is somewhat close to the thickness of a normal kitchen knife (the chef knife as people usually said. not those machete / butcher knife thickness). It's quite rusty too. So can it be done?

  • Note that it depends on the steel. And just in case anyone is wondering, serious safe manufacturers include a layer of wnat's called "hard plate" which is designed specifically to resist drilling. – keshlam Dec 5 '15 at 0:41
  • Can it be done? Yes. I think an edit to refocus the question for how to drill the holes you need might be more helpful to you. – Hari Ganti Mar 14 '18 at 21:30
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Most drill bits sold are "high speed" drill bits intended for a variety of materials including metal (but not concrete, tile, glass or extended use in plaster or plasterboard).

If the bits are fairly sharp, you should be able to use them in the steel, assuming it is not a hardened alloy. To improve your chances, a bit of oil or cutting fluid at the cutting point will help prevent overheating. Slower is usually better.

The rust probably makes the steel weaker and easier to drill.

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    1) use a center punch 2) if hole is to be over 1/8" diameter, then first drill a pilot hole with a 1/8" bit 3) to drill large holes, drill smaller ones first – mike Jul 20 '13 at 21:49
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    Drill bits marked HSS (high speed steel) are commonplace in my part of the world and are intended for drilling holes in steel. Almost any handyman's full-size electric drill will be able to drill small holes in steel. – RedGrittyBrick Jul 21 '13 at 9:09
  • +1 on hole punching first, followed by a pilot hole. If you want to drill bigger holes, then get an appropriate step drill bit. High speed cobalt, or at least titanium coated. It took me quite a while to do a 1" whole with my battery powered impact wrench, but it did work. I applied plain old water to the area while i was drilling. I had to stop and restart because my drill ran out of battery. – EdwardM Dec 20 '17 at 23:01
  • At home I use used motor oil as a cutting fluid, at work we have cutting fluid , using an oil will help keep the bit sharp longer, also don't use high speed, if you are drilling and get nice long spirals of metal you are going at the correct speed, if your chips are turning blue you are going two fast and the excess heat will wipe out a high speed steel bit rapidly. – Ed Beal Mar 6 '18 at 20:11
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Drilling steel is easy, once it is marked and punched. I would use a 4 or 5mm high speed steel bit. It needs to be sharp, and sharpening it is a trick: you would need to be shown, as I can't easily describe the technique in words.

Drill on faster speed pushing fairly hard, with some sort of oil (CT-90), by piloting you remove the very centre, which in effect you are not drilling, you are just forcing the bit to push the steel to the cutting edge.

From there you can open the hole to the desired size. For any size from about 9mm I would use the slower setting, and personally I would only drill up to a 14mm with a pistol drill. Keep a tight grip! For anything bigger use a pillar drill and keep the work clamps; the drilling speeds vary depending on size and material, you can look this up.

If you do come across stainless then half all drilling speeds, and keep the cutting constant as stainless will work harden. Brass needs to treated the same, aluminium and coppers are softer and you can nearly double the steel speeds, use appropriate cutting compound for the type of metal.

  • Fast speed on even mild steel creates excess heat and will dull the bit quickly. – Ed Beal Mar 6 '18 at 20:12
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When drilling metal the bit does not need lubrication! What it needs is cooling for the excessive heat, instead of oil use cutting fluid to cool and save your oil for lubrication B)

If it's too small a job to warrant buying cutting fluid, use water in a spray bottle to cool down your bit. Cutting fluid is a water-oil emulsion itself.

Also, make sure you're starting with a pilot hole before swinging straight for the fences. Even with a drill press, it's wise to always start with a pilot hole and expand it from there.

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If you are using a drill bit suitable for steel, then yes, providing the drill itself has enough power, this will be fine.

Even a low power drill can do this successfully, you will just need to take it slow in order to avoid getting the bit stuck. A higher power drill will manage without much of a problem.

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As long as it is not hardened and tempered like a knife (which is somewhere between "the drill bit is not that much harder" to "it's harder than the drill") - yes. But even in that case, you would just need a different drill bit, not a different drill.

Something obvious to most here should still be said given that the question implies the asker may be really inexperienced with an electric drill:

Many electric drill can be set to impact (eg for drilling concrete) and non-impact mode (eg for drilling wood). Be sure to choose non impact mode for steel.

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