drilling steel?

Yes, it works fine. Note the qualifier "old"

Reply to
Andy Dingley
Loading thread data ...

A lot depends on the hole size, and the rigidity of your drill press / hand drill.

If you try to drill 13mm straight off with a hand drill, then there's the potential for so a slight difference in cut depth from side to side turning into a considerable off-axis force. The hole is likely to wander like crazy, possibly with injury.

If you're drilling on a rigid drill press, then even then you can have problems with thin sheet (and I mean

Reply to
Andy Dingley

When drilling thin stock, it's hard to beat a step drill. Makes a rounder hole (more round?) and is far less likely to snatch the material.

John

Reply to
JohnM

What are you drilling these holes with? Bench drill or what? I'm not an expert but make sure you lubricate the bit, use even pressure, drill a pilot hole(!), use a properly sharpened or new bit, keep the revs down. It *is* mild steel you are drilling isn't it? Sure? Maybe try working up to that size using smaller bits.

Reply to
dave

Better still to use a Q-Max type punch. Although IIRC 3 mm steel might be a bit much.

Reply to
Dave Plowman

In article , Bruce Simpson writes

Not really -- use WD40 instead or, failing that, water applied from a hand spray. Even if the water doesn't lubricate the drill bit, it will at least help to keep it tolerably cool.

I must admit that, whilst I've not tried it as a drilling coolant or lubricant, I have used "I Can't Believe It's Not Butter" [1] when turning stainless steel; it seemed to work reasonably well, though the workshop stank like a chip shop for days afterwards.

[1] I'd bought two tubs in a B.O.G.O.F. supermarket promotion and, on tasting it, I soon decided I'd been overcharged on both. There again, I'd doubt that anyone could pay me enough to *eat* the stuff...
Reply to
Paul C. Dickie

In article , Paul Hewish writes

IIRC, those "Piranha" drills are impossible to regrind to the same profile and may have too thick a web for a conventional re-grind.

formatting link
or, to download (18Mb),
formatting link
But if you follow earlier advice about pilot holes (lots of them

Except that, by then, the final hole may have wandered a little from where you'd like it to be.

The cutting point of a twist drill is meant to be the "chisel edge"; by drilling a pilot hole, you're making the drill cut on the flutes rather than the chisel edge and therefore the drill will faithfully follow the pilot hole. However, as the smaller drill is thinner, it is also more flexible and may have deformed or deflected as it was fed into the work- piece. Yes, it's a lot easier to drill one or more pilot holes, but it may not be as accurate as drilling with the "right" size of drill.

But then, if one really wanted accuracy, one would drill slightly undersize and then ream out the hole to the final diameter...

Reply to
Paul C. Dickie

buy a pillar drill. Get some good quality metal drills, I bought a set from machine mart for about £30, sizes from 1mm to 13mm. Skimping on equipment will get you nowhere.

Reply to
Mark

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.