Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

You really do have excellent command of technical language, so that your explanations are very understandable. I fully understood the indexing and diametral pitch from your earlier explanations, but was unclear about how your guide remained in contact with your follower through both forward and rearward movement, so was hoping to see the action on that side of the fixture. I now understand that it is only manual pressure that keeps the system properly engaged, so that a moment of inattention, slacking off on the contact pressure while rotating the shaft, would ruin your workpiece gear, as there is no "failsafe" pressure system, like a spring or captured groove, to otherwise assure proper guidance.

Thank you very kindly for taking the trouble to clarify this point and help me with my understanding of the fixtures function and process.