Torque required for hammer to self right?

[Coolspeedbot]

I used a cordless drill motor as an axe motor on a 5:1 ratio. In short, no. There are small steel pins inside the drill gearbox that keep the small pinion gears in place, and the forces from a weapon like that just cause the pins to fail (basically falling out of the holes in which they're mounted).

If you want to go for an electric axe, have a look at electric scooter motors on eBay, specifically around 300-350W power rating. I changed my drill motor on the axe to one of these and they are vastly superior. On the same ratio the axe hits a lot harder and faster, and the motor can definitely take it. Sam also uses one for his robot Hatchet and has it working well for him.

something like this?

http://www.ebay.co.uk/itm/24-VOLT-30...AAAOSwBLlVcco6