Radius of the Winch Drum?

Greetings VEX Forums.
I have to design a gear train so that the torque applied to the motor is low enough for the motor to not burn out. Therefore I need to know the torque created by the 10.5 lb weight on the other end of the gear train. I know that the string holding the load is wrapped around the winch drum from this Winch and Pulley Kit:

But I for the life of me cannot find where it says the radius of the winch drum; I need that value for the project. Does anyone know the radius of that winch drum?

The CAD drawings are on the page you linked to. Looking at the picture and knowing that VEX holes are on 1/2" centers, I’d guess a diameter of 3/4" or a 3/8" radius. That should get you close enough for your project.


3 things. Post this under a VRC or EDR catagory, not IQ so more people will see it.

The winches drum is about 1/2 in diameter, but I don’t know the exact size.

A worm gear will give you much more torque if I’m understanding your situation correct

The drum is tapered from the center of the drum. At the widest point in the center where the string attaches, the drum has a radius of 0.358"


I checked the CAD file and the drum is indeed tapered so the radius can only be estimated from the lowest end (edge) to the highest (middle). The diameter is about .640708 in.