peter michaux <porkproducts@home.com> wrote

So thanks to everyone here, over last two days I have learned a fair amount
about CNC and the different types of retrofitting. I think I will definitely
fit my drill/mill to be a 3-axis CNC machine.

I think the best way to go is get one of the "complete" kits so I am only
required to mount the motors and connect the cables. The whole linux/solder
up my own stepper drivers seems to be a real pain in the butt. All the parts
come from different suppliers and I have no Idea if they will work together
or not. I am willing to pay not to go through it and am not into S&M:)

The two companies I found offered me the following solutions:

** From Ah-ha!
(http://www.ahha.com/cnc.htm)

- Pro-CNC software and card
- RC-500 Box power supply with stepper drives for 3-axis with cables, 6A
- 3 motors 450 oz-in bipolar 5.6 A, cabled, max rpm approx 1000

** From Super-Tech
(http://www.super-tech.com/root/ site doesn't load for me today)

- Controller with SuperCam software and printer cable
- 3 stepper motors 885 oz/in Unipolar Torque, 4.3 Amp/Unipolar Phase, 0.9
Ohm Phase Resistance, 6 Wire Leads, 0.500 Diameter Shaft with .125 Straight
Key, Pacific Scientific Model Number #N32HREK-LDK-NS-00
- Power Supply
- 3 10 ft. Motor Cables
The controller is unipolar, so ounce inches for the motors are the second
value given in the motor description given above. 885 0z/in.

Both systems are with in $50 of each other at about $2925 US + shipping.

So with the Ah-ha system the power supply and drivers are in one box. Also
the drivers are bipolar. There is a special computer card that runs the
whole show. The sales guy said that the system can "home" with
0.0001"-0.0015" repeatability using limit switches. I have to buy the
switches but the box is aready wired for them.

With the Super-Tech system the drivers are unipolar but even in bipolar mode
the motors have more quoted torque. However the system is run through a
printer port not a card in the back of the computer.

How much torque do you think I need for brass/aluminum on a mill/drill? I am
leaning towards the Ah-ha system but don't want to be underpowered.

Does the Ah-ha system drive the steppers more effently and therefore things
will work out anyway?

Any comments about or experience with either system?

Thanks,
Peter