How rack and pinion is used for indexing mechanism?

you need

a rack and pinion nut breaker to which you fix a pinion at the free end ie where nut is placed to be cracked. This is because you need to convert reciprocating motion of the rack and pinion mechanism built in the nut cracker into circular motion. Attach the nut cracker to the collect chuck shaft through the bore of the additional pinion you installed at the free end of the cracker. When you punch the nut cracker vide its handle once it moves the pinion one tooth on the rack. Thus you can rotate ( ie give angular motion to ) the fixed workpiece from one tooth or as many teeth as you like., depending on the pitch of the threads on the rack and pinion.

mazHur