CAD: Making a cam mechanism

[Greg Needel]

Originally Posted by JesseK

A very slow transition is what I'm after actually. The application for the cam is to act as a lock against a sliding Stackerbox transmission that acts as a low-maintenance chain tensioning system. The cam itself will have very little force put on it since the 4 bolts from the transmission will be tightened into the sliding plate, but the cam is necessary to make the overall tensioning system more reliable.

A symmetric cam may work just as well as what I want, but if I can have my cheese and eat it too then for now I will. In all actuality, to create the actual lock from 1/4" aluminum plate (I'm also looking into hardwoods) on a CNC, it will take either two passes for setup, or the final 90 degrees of the cam will have to be manually cut.

Gotcha, I didn't realize that you were looking to use the over center cam for a long actuation, I was looking at the short transition side of the cam. I still think for a tightening mechanism a symmetric cam would would, and you could always cut a flat at the extent to act as a lock. Either way they should both work. Have you thought of how you are going to lock the cam in position yet if the tension required is somewhere before the over center feature?