6' x 4' Tumbler finally done

Look for a used fractional hp gear motor, you can easily go down to a 1/6 hp. How you are doing your final drive (ratio) will determine the gear reduction you need. Example, if you are laying the barrel in a cradle, and the wheel on the drive axle is six inch dia. and your drum is twenty four inch dia. you have a 4-1 reduction, so a 1725 motor is now down to 431 rpm. So, if your goal is around a 10 rpm drum speed a 40-1 reduction on your gear motor will get you close at 10.78 rpm. Different motor speed and diameters of any parts will change your final, just use the same principle and plug in your numbers.

 

Reading through some of the post, I built a 4' x 8' tumbler. I started with a 1hp, 3" output pulley to 10" drive pulley on a 40:1 gear reduction to the tumbler. The 1 hp struggled with full weight, so I bumped to a 2hp motor no issues and it all comes out to around 12-13 rpm at outside diameter of tumbler.

 

Great article , I have the old Con-tan tumbler. For large drum 2 hp and speed reducer. The only thing I would change it would be chain driven, 40 chain. You do not have to worry about wear , slipping or tear. You can tumble large bulk. And to clean the hides you replace with the plastic fine mesh screen with holes in the plastic around the drum.

 

I just replaced the belt on my clothes dryer. The drum of the dryer acts as a big pully. Belt goes around a very small pulley on the motor and around the big dryer drum so it's just like a small pulley/big pulley setup.