I've looked around (Google, Machinery's Handbook), but can't find the
I am running an endless wire rope (stainless steel throttle cable, about
1.5mm dia) with a powered wheel ("drum", "capstan", whatever) to drive
it. Now I am sure there are somewhere formulae giving the proper drum
diameter, & size & shape of the groove for a given rope.
Can anyone point me at these?
I have the 21st and 26th editions. Both have a section on wire rope.
In the 26th the groove dimensions are given in a chart on page 360 in
the chain section. In the index it is called the "drum score
dimensions" or something like that. The chart is not the same as the
21st edition. I believe it's a mistake in the 26th. Anyway, for 3/8"
rope, which is the smallest listed in the drum score chart in the 21st
ed., the pitch is 7/16" and the radius of the groove is 7/32". So that
gives you some idea of what you will want for your 1.5mm stuff. But if
you look in the wire rope section of the book you will find all the
info you need for drum sizing. The drum diameter is a compromise. The
larger drum gives longer rope life and the smaller drum is cheaper,
will spin faster, and result in shorter rope life. Look in the index
under "wire rope" and you'll see the section pages.
Next time you get near a carnival, look at the drive mechanism on a
Tilt-A-Whirl. It uses an endless cable driven by a two groove capstan and a
two groove idler/tensioner. Simple, neat and effective...