Newbie needs help with 4-axis CNC mill.

[jnymarkp]

Hi everyone!

I am all new at CNC, but have had the dream og designing my own CNC lathe/router/mill for several years now.
After spending countless days and hours on google, youtube and cnczone, i have now taken the first babysteps into this wonderfull world.

I have set up a computer with Ubuntu Hardy Heron and EMC2, and bought three steppermotors and the first electronic components to build a PIC programmer and the stepperdrivers.
The setup i have chosen is a 4-axis moving table, fixed gantry.
First building xyz, then come time and money the a-axis and at last an automatic toolchancer.

But i have a few questions (many more to come i'm sure):

1) Which CAD/CAM software could be recomended for at total mill/router newbie like myself?

2) The steppermotors i have bought are from Step-syn and are marked DC 3A, type 103H6707-0741, FH6-1176 01.
Also i have been lucky enough to get my hands on some free DC power supplys, delivering 53VDC at 22Amps.
Unfortunately i have not been able to find any datasheets for my motors, so my question is,- can these motors be run with this power supply if i insert a current limitting cirquit between the ps and the steppercontrollers, limitting the motors to about 2A?

3) I have run latency-test on my computer with a result of about 14.500.
First i started firefox, showing a DIY CNC movie on youtube, then started three sessions of glxgears, and at last started latency-test.
The result where fine as mentioned above, but when i closed down firefox, the numbers skyrocketed to about 150.000!
Now,- is my computer just not powerfull enough to run EMC2 or is it just firefox taking up that amount of power when shutting down?
I realize of course that firefox would never be running while EMC2 was working.

4) Would this maschine be able to cut steel and aluminum, if accuracy is preferred over speed?

[svenakela]

1. Do you want to run everything under Linux?
2. Sounds not very heavy duty to me, I think you may need bigger steppers. But on yhe other hand you don't tell the size of the machine and screw pitch, or did you plan to use belts?
3. 150 000, did you check the latency test chapter at the cnc-linux webpage?
4. See 2.

[jnymarkp]

Hi Svenakela, and thanks for your reply!

To your questions:

1) No, I have both windows XP SP3 and linux running. I just imagine linux to be a better platform for the MILL control. The CAD software can run on both windows or linux. Either one is fine with me.
My only concern is the cost. Times are harsh and money hard to find.. so freeware is preffered.
Also it would be nice to use when designing my mill - easyer to share idears that way.
2) Sorry, my mistake - hard to answear my questions without all the details.
Dimensions: X: 800mm, Y: 600mm and Z: 300mm total (Travel 400/300/150mm). I am planning to use linear rails and 5mm pitch ballscrew for X, Y and Z axis. Stepmotors would be run at halfstep giving 400 steps/rev. Ballscrew would be driven via pulleys with a 2:1 gear ratio.
Not having the datasheets is a bit of a problem, since i don't ave a clue about the size of my motors.
What - in your oppinion is a heavy duty stepper?
Wich numbers should i look for?
If i need bigger steppers, wich axis should have them first? X and Y ?
3) Yes, i have read it, over and over again. I think my computer gives fine results (below 15.000). Only the closing of Firefox kicks the numbers thrue the roof. Bu tfirefox would never be running while controlling the mill.
4) Se 2 ;o)

[svenakela]

There's a rough estimate for steppers on the Gecko web page: http://www.geckodrive.com/support.aspx?n=541652