Thread: trivia - trisecting an angle & gradians

This is how I read it ...

Anyone can gauge a full rotation perfectly accurately, assuming the fit of the shaft and etc parts, with just a single mark.
If everything else is up to scratch, then 1 rotation will bring you to the same place every time,
and with eg a 40x reduction gear, each full rotation should give you precisely 9^o on your workpiece.

So eg to mark 40^o on your workpiece, you need to move 36^o by full rotations plus 4^o by a part rotation (of the divider).

The part rotation will be 160^o on the divider, which we assume is accurate to +- x degrees.

So the resulting movement of the workpiece will be 4^o +-(x/40) degrees ... total movement 40^o +-(x/40) and you've increased your accuracy 40x now.

Cheers,
Paul

Originally Posted by steamingbill

Thanks that was fascinating. Terrific video, will be looking at rest of that numberphile site for a while. anybody gets this far without watching the video then go back and do it.

I've slowly worked my way through the whole lot of them and, on the whole, they're all fascinating. The same guy has channels on physics and chemistry as well, called Sixty Symbols and Periodic Videos respectively, for those interested.

Originally Posted by elanjacobs

I've slowly worked my way through the whole lot of them and, on the whole, they're all fascinating. The same guy has channels on physics and chemistry as well, called Sixty Symbols and Periodic Videos respectively, for those interested.

And he's an aussie from ... South Australia (I think). Brady Haran.