Adding sprockets to 28mm acme vice screw

[Stevekane]

A wild idea from someone who is quite ignorant in these twin vice setups, why bother gearing them at all, why not use say a V belt and a couple of pullies which would give enough friction to wind in the “other” screw so that you then just had to go over and nip it up,,,which as a guess you might have to anyway with even the most sophisticated setup?
Steve.

 

[Jameshow]

How about getting 2x single speed bike sprocket and tack welding or chemical metal them to the vice handle castings. Then a 1/8 chain between the two?

If you need the slack taken up you can get a fixed wheel tensioner.

Just a thought.