adding cnc 4th axis to manually operated Bridgeport with a s

[oscer]

Hi fellas, I did a little reading and tried to search threads but didn't find any of the specific answers I'm looking for. I was wondering if it would be possible to tie the servo power feed on my Bridgeport into a mach 3 program and use a second motor to torn the gear blank, to cut helical gears or flutes.
I saw a universal dividing head sold by Shars which included a gear set for $800 but it appeared that I would have to build a framework and cobble something up to attach the lead screw trough the gear train to the dividing head. this may in fact be the less expensive route but probable not as versatile.

[hwboivin3]

I have a dividing head that was built for just that. It has change gears that tie into the handle on the Bridgeport. You set the ratio you want and the dividing head rotates as you crank the handle.

Unfortunately, I've never needed to use it, so it's been sitting under my bench for years waiting for the day when I'll need it.

I think Bridgeport made it, not sure, but I'll get more info if you want.


Harry

[hwboivin3]

This is what I'm referring to.

[Dave_C]

Oscar,

What is possible and what is practical? It is possible but given the cost to modify your servo driven power feed it might be more cost effective to just remove it and install a stepper or servo motor with the proper motor driver.

Then Mach 3 can send step and direction signals to the driver with no unknown issues.

Then put a similar motor and drive on the dividing head and yes, it will move back and forth and turn for the tooth steps.

What it will not do is set the depth on the Y axis so as to clear on a back stroke.

Tormach makes a 6 and 8" RT with the stepper on it as do some other manufacturers.

Then we have to deal with backlash. Not such a big deal on the X axis as it will clear the gear going both ways but the motor and backlash on the Dividing head needs to be dead on.

Just my thoughts,

Dave C.