Some good progress made today in the continued conversion of my milling machine to a CNC machine using Dave Rigotti's kit from Hobby CNC.
I've been working on a way of interfacing the stepper motors via an engineered belt (also known as a timing belt) to the existing hand wheels used to move the table.
I've come up with a replacement part that will allow me to mount the driven cog to the acme screws of the milling machine. Click on the images for a larger view.
I started with 2 1/2 inch diameter steel stock
Bored out the correct size hole for the acme lead screw shaft
Turned part of the interface to the right diameter to fit the hand wheel's teeth
Set it up on the milling machine to mill out the interfacing teeth
And voila! The part I made is on the left. The handwheel is on the right. You can see how the two mesh together.
Bringing the two parts together.
The fit is perfect!
I placed the timing gear on top of the interface part I made to give you an idea of its function. The timing gear will be attached to the interface part which will in turn (pardon the pun ) drive the acme lead screw.