I am 99% sure I am going to buy an X3 mill very soon, How much will it cost roughly to 3 axis cnc the thing? Assuming I already have a dedicated computer to control it. no ball screws. I can make the motor mounts and couplers my self, What else do I need? Motors etc...

James,
I guess I can get you started. Since you want to use the standard acme screws, you will be looking at the cost of the controller, software (Mach3 is $159), and the stepper motors, and the Drivers.

I'll put you in the ball park.

Controller - 3 gecko drives (about $115 each) $345
bread out board ($15) - break out the 25pin parellel port and give solder points
Transformer $50 (guess)
Large cap (approx. you nail down with design40,000 uF) $25
4 way bridge rectifier $3
Fan $10
approx 470 2 watt resister (bleed for capacitor when unit is turned off)
hook up wire (18 guage) in side box) $10
fuses 1 each for gecko's (3), 1 for AC input $5 total
fuse holders (4 ea.)$4
terminal block (maybe 10 position) $5 (Good place for interconnection)
30 ft of 18guage 6 conductor stranded wire (.60 ft) 18
pins and connectors (Molex ) guessing $15

Stepper motors Need larger because you are using acme VS ball screws, this you will have to figure out (guessing $100 each)

Some use a gas spring on the head to off set the weight of the head like a counter weight (another guess $80)

Guys, look over the list and see what I missed and suggest Stepper motor size based on using Acme vs. ball screws (lower effec.)

Good hunting
Ron

i know you said no ball screw but honestly you should really rethink that cuz a ball screw as alot to do with the effectivness of a cnc... but its your choise

I am looking for NIgata-Japan VMC parameters,

PC parameters

Keep relay parameters

RAJASEKARAN

good list Ron, maybe addon limit switches, maybe heavy duty bench if you dont have one.

Then i guess unless you dont have it endmills/drills ect,hold downs,collets/tool holders.

I specified no ballscrews thinking i could upgrade in the future, can I compensate for acme backlash/slop in the program? Didn't realize I would need larger motors for acme. I have endmills/drills ect,hold downs,collets/tool holders, boring head, vises, paralells, etc already.

A typical ACME screw will transmit 25% to 35% of the motor's torque into movement... ballscrews are 90%+ efficient
From 5bears.com

http://www.cncfusion.com/smallmill1.html

Ballscrew kits available there.

Ron,

You are suggesting using a $15 Breakout board to connect Geckos. I guess this breakout board is not buffered. Keep in mind your parallel port delivers a max of 10 milliamps and Geckos require 16miliamps. I know in most cases they work fine, but it is just a matter of statistics and probability. It all depends on the saturation capacity of the optoisolator you get inside the gecko.

Arturo Duncan
http://cnc4pc.com

"compensate for acme backlash/slop in the program"

Yes and no , yes you can but most time doesn't work well for what i have seen.

Does not work that well, acme screws will wear. I notice wear just using my X3 manually. CNC, it will see a large amount more use, and you will constantly have to be adjusting the nuts, and predict how much it has worn. By using ballscrews I am able to save a bundle of money for my CNC conversion because I can use 23 frame motors and lower power drivers.
You will find with drivers that anything below the 3amp mark is not too expensive. Once you get above that, cost rises quite a bit. You can get ballscrew from Industrial HObbies, 6ft length for 51 dollars. Plus 23 per nut, much less than the cost of higher power steppers/drivers.

actually like everybody answered you and as i said in my post ballscrew is at least responsible for 50% of the cnc effectivness so the expense is more then worth it providing way more effective movement of the axis translating in way more precision
i remember at school they had a manual mill with ballscrew on it and you where able to feel the difference when working with it