[SwarfEye]

Hello,

I am looking to break into CNC, and I am having some trouble figuring out where to start out.

I should say that I am a reasonably good manual machinist with a good deal of experience doing prototype fabrication work. I am also a reasonably good computer programmer. I am familiar with Linux and do a lot of microcontroller programming using open source tools... primarily in C.

I figured that I shouldn't have too much trouble cutting my teeth with CNC stuff. Given that I am an opensource nut, I was immediately attracted to EMC... hence my posting to this forum.

The first thing I want to do is get a stepper motor and just get it to turn to the location that I want using EMC. I figure that once I can get this basic setup working, then hooking the thing up to a lead screw, and adding more axises will be mostly a matter of hardware... which I'm pretty comfortable with.

It seems that EMC has got lots of bells and whistles that I will need to learn as I get more complex, but for the time being I'm just trying to get some really basic motion control under my belt.

But I'm sort of lost on where to start here. I was thinking about picking up some run of the mill stepper motors on ebay. It looks like I'll be needing some kind of "controller" but I'm not sure how to figure out what exactly will fit with what. Also, I'm not sure how these controllers want to connect to my computer, and then how to configure emc to run the controllers.

Is there a "CNC for idiots" type web page that I can get started with?

Any guidance will be much appreciated.

Thanks so much.

B

[chester88]

lots of info on the EMC wiki:
http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl
A old but still good tuturial for stepconf (a step direction configuration program):
http://www.distinctperspectives.com/emc2installsetup/
EMC's trial forum:
http://www.linuxcnc.org/component/op...mid,0/lang,en/
There is also a maillist that you need to register for and irc.

[chester88]

The simplest way to control something with EMC is using stepper motors with stepper drivers through the parallel port.
you can also use stepper motors with stepper drivers through special hardware cards.
you can drive analog signal (eg +-10 volt) servos with encoder feedback using special hardware cards (you can do this through the parallel port too, but the speeds are slower). This give true closed loop servo control.
you can drive step and direction servos with EMC (this is not true closed loop servo control)
here is a list of known supported hardware:
http://wiki.linuxcnc.org/cgi-bin/emc...orted_Hardware
I would suggest using stepconf to help you configure EMC since you are wanting to use steppers.

[CalG]

Same ideas any way, You are ahead of me with your programming skills though.

I have "opted" to purchase Compumotor S6 controller/ drive units off e-bay. (<$75) Very good units with lots of flexibility and integrated power supply. Just plug 'em into a wall socket.
With a CNC4PC breakout board for the parallel port, and a little time with both EMC2 online info and the Parker handbooks, the required pin assignments were easily worked out. The stepper setup application in EMC2 goes a long way towards success. Viola! Turning motors!

It's one way

CalG

[cyclestart]

Hello SwarfEye

I really doubt you need anything labeled 'for dummies' but this site is pretty good;
http://www.cnccookbook.com/

To do step/direction via parallel port you need a driver, a stepper motor , a power supply, and an interface for the parallel port cable. Many drivers have a built-in pp plug. Buying the electrical/electronic stuff before having a final machine design would be a bit backwards.

I'm building a few emc powered toys atm and looking for some low cost ways to drive them.
The stuff on the wiki is to expensive and I lack the skills to roll my own.

edit/ this might be more relevant;
http://pminmo.com/PMinMOwiki/index.p...ystem_Overview
one of the emc developers uses a pminmo designed driver