Back to photostream

Rack & Pinion

A rack and pinion is a type of linear actuator that comprises a circular gear (the pinion) engaging a linear gear (the rack). Together, they convert between rotational motion and linear motion: rotating the pinion causes the rack to be driven in a line. Conversely, moving the rack linearly will cause the pinion to rotate.

Wikipedia

 

This Pentax bellows set was purchased in Thailand while I was stationed there in 1972 (USAF). At some point in the early 80’s a friend milled out the Pentax screw threads and machined a Nikon bayonet mount into what was left. He used an indexing rotary table on a Bridgeport vertical mill (a really talented guy).

I have been using it on occasion for over 50 years. The Spotmatic II that I bought it for lasted about 7 or 8 years.

 

The frame is 1.5 inches wide.

866 views
62 faves
4 comments
Uploaded on November 24, 2024
Taken on November 24, 2024