Posted by JasonB on 22/01/2017 17:15:46:
Does seem a lot of levers and pullies for little gain over a lever that could just have been pulled down avoiding the inherent slop in the linkages and giving better feel.
Not sure I would want to be doubled over close to that drill with a loupe in my eye and the belts passing straight past my head
I did wonder if a length of cord could have been hooked over the end and down to a foot operated board thus leaving both hands free. Or maybe you could rest your elbow on the lever and keep two hands free.
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Possibilities, yes … But if you're drilling a 0.1mm hole, I suspect that maximum sensitivity is obligatory.
I can't find a picture of anyone actually using such a machine, but the posture illustrated at the top of this page is pretty common. **LINK**
http://www.historictimekeepers.com/Staffsteps.htm
MichaelG.
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P.S. … I haven't worked-through the geometry of the linkages … perhaps Martin could give us some dimensions when he strips it down. The result may be interesting.