CNC for DRO X3

[AirHog]

So i'm in the DRO vs CNC debate as we all seem to go through (well most) My question is how effective can i have Mach3 act as a DRO if i use hand wheels at the back of the motors for manual operations with steppers? Will i have to do everything via the keyboard for the positions to be read?

Now if that is the case would it be feasible to do manual milling operations using the jog features? or would a rotary encoder be my best bet for that? Oh and did i mention this would be on stock screws

My basic reasoning behind all this is that i want power feed for my Z for quicker tool change, and i want a DRO. I can drop 300 to get a DRO going, or i can drop $300 to get motors and drivers and basically use them as a power feed for the time being until I'm ready for the ballscrew upgrade. I already have the power supply's, computer, Mach software, Rhino 4, and Rhino cam, and i would be making all the adapters myself, so it seems a waste to get a DRO for the same coin.

But all of this is for nothing if i cant reliably use the Mach3 software to do manual milling. Sorry for the long winded post, I've searching around for days now but theres some blanks i just cant fill in without initial experience.

[M100]

Turning the stepper rotor by hand will do nothing except move the leadscrew. Mach 3 won't know it has moved. You could have rotary encoders on the leadscrew feeding back into mach 3 as you would if fitting a servo motor.

You could also convert the steps from a manual pulse generator to directly drive a stepper motor, but for the cost that a few stepper drivers, a breakout board and an old PC you'd be better off going the CNC route, but with MPG's either mounted on the mill or on a handheld controller. Three MPG's are going to run to about $250, you could conceivably get away with one, two are better and three better still

I had no end of problems with interfacing a rotary encoder directly to a parallel port breakout board so I got an MPG (singular) and a MODIO board from www.homanndesigns.com that plugs into the RS232 serial port on the PC and I use the parallel port for driving the stepper drivers and some the limit switches.

The new Geckodrive.com Gecko G540 is looking like a good cheap option, the BOB and pluggable driver boards for 4 axis steppers in one box for $300