I have a right angle gear box with 1" shafts which I am using to make a
firewood saw bench which will run off the PTO of my tractor. The gear box is
a 2:1 ration. 2 pinion turns = 1 ring gear turn. Can I use this the opposite
way and put power into the ring gear shaft and run my saw pulleys off of the
pinion gear shaft. Can these gearboxes be used either way or does the power
have to enter through the pinion gear? Thanks

You do this all the time in your car when you decelerate. Seems to work
just fine.

The question for you is: does your PTO have enough torque to operate
your saw? The current setup has a two-to-one reduction so torque is
doubled (ignoring losses). Going the other way, your torque is cut in
half.

Another question comes to mind. Will the shafts connect to the PTO? How
long do you intend to run the double speed and what is that speed? If
you run 440 rpm in and get 880 out, will this be enough speed for the
saw?

Paul

15-18" blades need about 5hpof electrical powe to run well. If your gearbox
can handle that much torque in the reverse direction, I see no problems with
doing so. I will note that a worm and wormgear box in that ratio would be
kind of unusual as the worm setup is more for higher ratios. Miteer
gearboxes in that ratio are a lot more common and are easily driven
backwards.

--
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