You might have a motor already, and considered belts to be a good method to
reduce the speed, sometimes they are not.

You might want to consider gear reduction instead. A gearhead motor, or a
separate gear reduction box could be a better solution.
Worm gear reduction results in an output shaft that is 90 degrees from the
input shaft, and parallel gear reduction results in an output shaft 180
degrees from the input shaft.

You would need to determine how much final drive torque your project machine
will require to select a suitably rated gearbox.

If this machine is related to the earlier questions about making a smooth 5"
to 8" disk, the torque requirements shouldn't be very great, and a
fractional horsepower motor with gear reduction would probably be
sufficient.

The output of a gearbox shaft can be used as a direct-drive for the platter
with a shaft coupler, or a chain and sprockets can be utilized to change the
output shaft speed to optimum.

WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html



"Michael Koblic" wrote in message
...
I am not sure if I am going crazy or the world around me is:

I am going around trying to price out a project: To reduce motor speed
using a pulley system by 16:1 would cost me in pulleys alone $50 using a
local supplier (2 6" and 2 1.5" pulley). I have just come back from an
auction where one could buy several drill pressess for around $40. For
this I have two step pulleys, a motor, a shaft, some bearings etc.

Since when has it become cheaper to buy an assembled piece of second-hand
equipment and cannibalize it for parts rather than buy parts alone? Come
to think of it, it would not even have to be second-hand equipment: Plenty
of cheap small drill presses for $100, i.e. a cost of 2 step-pulleys
alone. BTW a single sleeve 1/2" bearing - $5.00.

Is this an atypical observation? Is this a common phenomenon in the USA
also?

--
Michael Koblic,
Campbell River, BC