Shopsmith Forums

Hi

Just so we don't get to confused... the speed reducer uses 2 matched belts to change the speed, clearly shown on the exploded view on page 6 of the manual. No "gears" inside.

I was thinking more last night about the idea of two of them and the solution might be as simple as using a shopsmith coupling between them and solid channel between the clamps... then maybe some sort of metal piece across the tops using the top two screws of the cases (threaded rod)???? The coupling if it could "take it" would of course be the failure point.

I guess I'd like to go from difficult to plausibile, this is of course without actually trying anything I've said.

Ed

I have a tendency to oversimplify things and talk about things I don't completely understand. But if the speed reducers are simply belt and pulley's couldn't you simply change a pulley diameter to reach the speed you want?
ed

Ed:

I just received a Shopsmith speed reducer and have unpacked it and looked at the owner's manual. In regards to my earlier thread, I'm going to have to stand corrected on one point. The Shopsmith speed reducer has two internal belts rather than gears. However, this doesn't change the essence of my speed and torque discussion above.

A second Shopsmith speed reducer, in tandom with the first, could have an outspeed as low as 14 rpm. In order to be able to transmit the headstock motor's 1 1/8 HP, the final output torque at this greatly reduced speed would exceed the design capacity of the second speed reducer. It literally could be destroyed in an attempt to provide this much torque to a particular application.

Your question of simply changing pulley sizes is a good one. The Shopsmith speed reducer has two internal belts. In order to go from a reduction ratio of 7 to 1, to 50 to 1 (approximating two speed reducers in tandom), a third and possibly a forth set of belts and pulleys would be required, or perhaps even better, a set of gears. This of course would make the speed reducer much larger in size and much heavier in order to transmit 1 1/8 HP at only 14 rpm.