Re: ATM - More Grinding Machine ideas

["Peter John Smith" <pjifl@bigpond.com.au>]

A mixed bag of ideas.

Very large wooden pulleys can work well.  Having a lathe facilitates making
them.  I have a machine that uses a mixture of pulleys including multispep
ones from wood to keep costs down.  Large wooden pulleys last well but small
ones should be of metal to last.

It is probably easier to make them by using one piece of ply and and
building up the edge with bandsawn segments.

Extremely large pulleys do not need a V groove as there is a lot of friction
available simply on a long flat surface.  A V belt can be run on a flat
surface if necessary - if it is of large diameter.  The surface should be
wider so the belt stays on.  Old auto flywheels with the ring gear removed
can be driven well with a v belt if the edge is wide enough.  You do not
need a V groove.  Many flywheels have the ring gear removable - not all.

Pushbike wheels minus the tyre can be driven by a V belt but they are often
out of truth more than expected.  Often to be had for nothing.

M section belts are about 1/4 inch wide.  Plenty strong enough for these
uses.  The smaller belt section makes it possible to run them around
extremely small diameter pulleys which can help with large reductions.  It
is quite possible to turn M section pulleys fron a piece of 1/2 inch thick
Al plate with a V turned in the edge.  Even 3/8 will do at a pinch.  A multi
pulley takes up much less room than an A section one.  A 1/4 inch tool in
the lathe ground to match the V groove is about right.  A piece of 1.5 inch
diam Al bar can be turned easily to a 3 step small pulley to suite M belts.
Turning out A section pulleys on a small lathe is far more of a chore than
the M section ones.

If it is contemplated powering from a drill press, first check that it does
not run too hot over the timespan you intend to cater for.  Many are only
rated for intermittent use.


Now a question.

What are the common systems people use to automatically and reliably feed a
small amount of water or water/CeO mix to a lap and work during polishing on
a machine.  All sorts of things come to mind but there are probably some
extremely simple well tried systems that work well.

Peter Smith.