Homemade Speed Reducer

[edma194]

A metal cutting bandsaw or similar would be a better way to go.

Certainly. But if it were to be done with a Shopsmith bandsaw...

Another option would be to set up the Bandsaw on a separate stand with it's own motor. A 1715 RPM Motor with an 1-1/2" pulley going to an 8" pulley on the Bandsaw will run at 320 RPM's. An intervening step pulley setup could get it lower and could reduce the needed pulley size at the Bandsaw's shaft.

A second reduction stage is definitely needed. I think driving the bandsaw in the range of 50-100RPM should do the job for even hardened steel.

At that point perhaps the speed reducer should be considered. The 700RPM output from the conventional headstock needs at least 10:1 reduction still. The 7:1 result from the speed reducer is feasible though if care is taken. No problem at all if mounted on a PowerPro. I recently acquired a Speed Reducer, have only mounted it to make sure it worked, but did try it at 250RPM to watch it turn oh so slowly. Don't see any reason it can't mount on the left side of the headstock and drive a bandsaw with a carbide blade to cut steel. I still can't see why though, the feed rates will be incredibly slow and there are so many other ways to cut that metal.

[edma194]

A metal cutting bandsaw or similar would be a better way to go.

Certainly. But if it were to be done with a Shopsmith bandsaw...

Another option would be to set up the Bandsaw on a separate stand with it's own motor. A 1715 RPM Motor with an 1-1/2" pulley going to an 8" pulley on the Bandsaw will run at 320 RPM's. An intervening step pulley setup could get it lower and could reduce the needed pulley size at the Bandsaw's shaft.

A second reduction stage is definitely needed. I think driving the bandsaw in the range of 50-100RPM should do the job for even hardened steel.

At that point perhaps the speed reducer should be considered. The 700RPM output from the conventional headstock needs at least 10:1 reduction still. The 7:1 result from the speed reducer is feasible though if care is taken. No problem at all if mounted on a PowerPro. I recently acquired a Speed Reducer, have only mounted it to make sure it worked, but did try it at 250RPM to watch it turn oh so slowly. Don't see any reason it can't mount on the left side of the headstock and drive a bandsaw with a carbide blade to cut steel. I still can't see why though, the feed rates will be incredibly slow and there are so many other ways to cut that metal.

[miken]

A metal cutting bandsaw or similar would be a better way to go.

Adapting the Shopsmith Bandsaw seems to be a challenge. I wonder if the Speed Reducer can be made to work. That is an accessory I have not had. Can the Speed Reducer be connected to the Drive Sleeve shaft since the bandsaw needs to run in the correct direction? A reversing Headstock like the Power Pro or old Mark VII can reverse allowing the Speed Reducer to be mounted in it's normal position off the Quill. Second, can the Speed Reducer be run in the reverse direction? If not, neither mounting option will work. The Speed Reducer is a 7:1 reduction so it could go down to about 35 RPM's on the Power Pro Headstock as edma194 said.

Another option would be to set up the Bandsaw on a separate stand with it's own motor. A 1715 RPM Motor with an 1-1/2" pulley going to an 8" pulley on the Bandsaw will run at 320 RPM's. An intervening step pulley setup could get it lower and could reduce the needed pulley size at the Bandsaw's shaft.

I do have a reversing Mark VII, but I have basically given up on the speed reducer idea to cut metal. I acquired a nice Shopsmith bandsaw when I bought a backup Mark VII and wanted to find a reason to use it/keep it. I already have a stand-alone bandsaw. Anyway, it doesn't make sense when a Harbor Freight porta-saw can be had for $129 and that is really the tool meant for the job, variable speed, etc. I will likely buy a bi-metal blade and run it at the minimum Mark VII 700 rpm just to see.

[chapmanruss]

Ed,

I don't mean to be picky but the low end of the speed range of the conventional headstock is 700 RPM. I'm sure 500 RPM was an oops. I have needed correcting before and will likely need it again. I know we like to have good information here.

[edma194]

Ed,

I don't mean to be picky but the low end of the speed range of the conventional headstock is 700 RPM. I'm sure 500 RPM was an oops. I have needed correcting before and will likely need it again. I know we like to have good information here.

Quite right. I edited all three copies of the post while wondering how I got three of them and I think maybe I've hit the quote button instead of the edit button to make changes. And of course missing that one big mistake even after editing. Do not feel bad about pointing out my mistakes, the record has to be kept straight.