Suggestion to mount the crank wheels true and without 'wobble' to M3 bolts.

[flbauer]

Hello,

I have good results with driving flexures with M3 bolts by using a 4mm diameter cylindrical Nd magnet, a steell ball and a long M3 screw guided by a M3 brass diistance hexacon. The ball is placed between the magnet and the screw and removes wobbling almost completely. Bonus: nearly zero friction and this assembly can also pull the flexure. By embossing the M3 screw with profile of the steel ball could probably improve the situation further.
If screw runs too easy one can wrap it with teflon band.

best regards
Florian

[flbauer]

#1 I made a variation of the Flexure stage with a cylindrical 4 mm Nd Magnet on the shuttle. With 3mm ball between M3 driving screw and magnet I can push the shuttle . Because the restoring force is too strong the screw can only pull about 0.5 mm. By installing an additional spring that pulls the intermediate beam this limitation can be overcome. I don't know yet if applying force to the intermediate beam deteriorates the precision.