[TowerTalk] Motorized Winch for US Tower

[Grant Saviers]

> I think the point to remember is that drill motors are not designed 
> for continuous duty, not even the heavy duty ones. I burned up a brand 
> new, heavy duty Dewalt hammer drill, drilling 3/4" holes in a guy 
> anchor brace in under 5 minutes.
A tough gig, hard on the body and the drill.
>
> If you look at the motor driven winches, they use a monstrous step 
> down through spur gears which puts very little load on the motor just 
> as in the ham series of rotators.  The motor itself has so little 
> torque you can stall it with the pressure from one finger. Drill 
> motors OTOH provide considerable torque, but generally for a short 
> period as the motor is small and is not very efficient at getting rid 
> of heat. The larger rotators using a double worm gear have a  motor 
> capable of substantial torque although the double worm gear multiplies 
> the torque substantially.
The "Hole Hawg" is geared way down and I think will handle long on time 
duty cycles.  It's designed for drilling through lots of studs for piping.
>
> Variable speed Drill motors develop substantial heat when operated at 
> low speeds/RPM under load. they can not get rid of the heat 
> efficiently at low RPM and cooling is critical for these small 
> motors.  Two speed drills use gears and run the motor at full speed so 
> they have better cooling.
Here is my favorite, torque that can hurt, 2 speeds for metal or wood.  
I've drilled dozens of 9/16" holes in 3/8 steel plate non-stop using 
split point cobalt drills.  It wasn't fun.  A Mag-Drill would have made 
it easier but was too heavy to schlep to the remote site.

http://www.milwaukeetool.com/tools/rotary-hammers-and-hammer-drills/hammer-drills-corded/1-2-inch-dual-speed-hammer-drill-kit/5387-22 

$180 at HD.

It is also very fast as a hammer drill in concrete, but you need a top 
quality carbide drill bit and some luck in missing the rebar.

Grant KZ1W