Electrical 'Clutch' for winch

[aldaeron]

I think a few more details are needed for a good answer.

You mention a size restriction - what is the restriction?

What resources do you have? Just 12V power? Pneumatics?

Does it have to wind on a 1 inch shaft?

A sketch would work wonders here. A description of the task would too (especially so that you take safety into consideration since it seems you are working with a large load)

Another caution about using Banebots gearbox is that they have a torque limit after which all the gears inside shear off their teeth. I haven't looked in a few years, but it used to be 85 ft-lb.

One solution may be to adapt your motor/gearbox to drive something like this:
http://www.harborfreight.com/1200-lb...nch-65115.html.

To release you can drive the motor to release the load from the winch spool and use a second <something> to pull the stop out and unreel (you can use a smaller <something> if there isn't a lot of weight on the winch spool)

-matto-