Hadn't seen this before and I know it defies all logic but it's possible........

Cheers, Pewe

PS Blake V V probably have to be used in a milling machine or similar as the side forces must be considerable.




http://www.ohgizmo.com/2009/10/07/square-holes-drilled-with-a-watts-drill-blows-my-mind/

[Edited on 4/2/10 by pewe]

wankel rotary engine anyone? cool though

Very clever, kinda reminds me of a Wankel engine though !

Dammit..too slow

[Edited on 4/2/10 by NigeEss]

Interesting, I don't think I'll be putting one in cordless drill however.

That animation reminds me of a wankle engine.

Slow twice over on the wankle engine comment. Now I feel a right wankle.

[Edited on 4/2/10 by Irony]

WITCHCRAFT...... BURN THE WITCH

Is it just me or does this remind anyone else of a wankel engine?

it reminds me of something... i can't think what though

er, i guess it won't work in just any drill though?

I can't open the link at the moment but does it work like a Wankel engine?

adrian

As the article says - it's not a new concept. In fact, if you drill a hole with a conventional 2-flute drill bit the resulting hole will be slightly triangular. If you want a truly round hole you need to finish off with a reamer, which has many cutting edges and (usually) irregular spacing between them to reduce oscillations.

It must be slightly scary to watch that drill work, as it has to rattle around a fair bit to do its job - bit like a Wankel rotor in fact!

Hey... that works just like one of those funny Mazda engines. What do you call them again...

Presumably its more designed for milling applications rather than for bob to use with his hand drill :p

... and doesn't that take all the fun out of trying to fit a square peg into a round hole?

quote:

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Originally posted by scootz
Hey... that works just like one of those funny Mazda engines. What do you call them again...

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I bet the bits are expensive with all the side loads.

I once had to buy a lathe which 'turned' round bar into flat sided profile.

The bar went the normal way and the cutters, one cutter per surface, went the other! Swarf and coolant flew everywhere, all very complicated!

fantastic

I bet you'll find some of your donor bits have holes like that in them



...so how do they do hexagonal ones then ??

[Edited on 4/2/10 by mcerd1]

quote:

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Originally posted by mcerd1
...so how do they do hexagonal ones then ??

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Wankel Wankel Wankel! aaahh that's better

quote:

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Originally posted by David Jenkins
As the article says - it's not a new concept. In fact, if you drill a hole with a conventional 2-flute drill bit the resulting hole will be slightly triangular. If you want a truly round hole you need to finish off with a reamer, which has many cutting edges and (usually) irregular spacing between them to reduce oscillations.

It must be slightly scary to watch that drill work, as it has to rattle around a fair bit to do its job - bit like a Wankel rotor in fact!

---

quote:

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Originally posted by blakep82

quote:

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Originally posted by mcerd1
...so how do they do hexagonal ones then ??

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would have thought they're more likely to be water/laser cut can't think of where these holes would be right enough

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never looked at a pinto dizzy, but i see what you mean about cap head bolts. i always just assumed they were cast or something. or milled

Non-round holes are either forged (Socket capscrews etc.) or broached (keyways, splines etc.) or if thin enough just punched out.

BTW, I think the word you are all thinking of is Wankel

quote:

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ah, the mazda B series engine!

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think ill stick with my waterjet......but i like the spirograph pattern in the middle.......

I usually bray in my square section taper drift until the approximate size is reached, do the other side to even out the taper a bit, then grind off the overspill. Its a bit rough mind, but works for the 'smithies.

Wonk.., um, Wink...,er, dammit, me memory is going....
Where's me coat?
John.

Wankels!!