[nate]

hey folks. im new to here and new to building cnc.

i used to work as a "grinder hand" in a tool and die shop. i've run a cnc moore jig grinder that i had to modify feedrates in the g code, so im not totally ignorant of cnc.

ive got a hf micro mill right now. and i would like to convert it to cnc.

i want to go 3 axis, with enough power to do aluminum and steel.

i also plan to upgrade the spindle motor and run it with a timing belt.

i like the ballscrews and nuts available from http://www.homeshopcnc.com/page2.html
i have a surface grinder that i can do od grinding on, so i can make the ballscrew ends fit into bearings and i can make all the nessicary motor mounts and bearing houseings.

what i am not comfortable with is drive and motor selection. i do however really like the "400 oz/in Model # RHT34-400 Dual Shaft: $85.00" from homeshopcnc.

will they be powerful enough for my needs?

is the Geckodrive G201 good for them??

motors 3 x 85.00 = 255.00
drives 3 x 107.00 = 321.00
ballscrews and nuts 125.00

this puts my approximate cost at 701.00 not includeing all the bearings, aluminum plate, hardware and motor connection components.

will the dual shaft motors allow manual cranking when powered off?

what is a good way to couple the motors and ballscrew ends??

thanks,
nate.

[rexstep]

Nate, The RHT34-400 is very well matched to Geckodrives. It should be run at about 48 volts for best results. It has a nice low inductance value and therefore has excellent running torque. At high enough speeds it puts out more torque than RHT34-640 which itself is a powerful motor.

The dual shaft version will allow you to handcrank with power off.

-Rick LaLonde
www.homeshopcnc.com

[nate]

hello! do you work at homeshopcnc? looks that way.

will the motors and boards have the nessicary power to do work in aluminum and steel?

what power supply do you recomend??

and what else will i need (besides a computer and software)

[rexstep]

Nate, I have guys cutting mild steel with nema 23 260 oz/in motors. The 400's will certainly be strong enough.

There's a 48 volt, 10A unregulated supply at www.mpja.com for around $150

-Rick

[rexstep]

Oh yeah, I'm the guy at homeshopcnc

-Rick

[nate]

http://www.mpja.com/productview.asp?product=6646+PS

is this the one?

also, are the Jaw Type Couplings suitable for connecting these motors to the mills threaded shaft or a ballscrew?

thanks alot for your help!

[rexstep]

I've never used any other than Helical, bellows or the flexible disk type couplers as I'm concerned about backlash in other types. Couplers are a problem that has yet to be solved from the hobby budget standpoint. www.mscdirect.com has some reasonable solutions.

Yes, that the power supply. it will handle up to three 400's

-Rick