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Sparkfun CNC parts. Need a head start with project, need help with shopping list. Answered

First off, I know practically NOTHING of robotics and I have a plumber's understanding of electronics.  This has to be a "For dummies" project.  It's also important that most or all of the electronic parts come from Sparkfun, because I wish to take advantage of the great bargain they have coming up and because I cannot find anything locally.

That said, I have been looking at building a small CNC milling machine.  Something that can engrave and cut light materials like circuit boards, foam, and softwoods.  I want to at least be able to engrave steel as well, but I feel that is up to the tool attached to the milling machine.

The machine itself is not a problem.  I understand the mechanics of it, have the tools and know-how to produce, find or buy all the required parts.

The trouble is the steppers, driver, and software.  The more I look at it, the less I understand.  Let's get to the questions I guess.  There's a lot, I'm very sorry.

-Are there any well-documented projects here or on the web using mostly Sparkfun parts?
-What is typically involved in setting up a stepper controller/driver?  Will I need to flash anything?
-What software is best for operating a CNC from a windows or linux PC?  As a printer driver?
-Out of the motors available on Sparkfun, which will give me the highest resolution and which will be strong enough to move up to five pounds of material without trouble?

I know I need a lot of hand-holding here, but I really want to get started on this and I really want to take advantage of that sale.  It seems like the perfect time to begin.  Please help!


I've given up on this one, there's still a lot to learn and I now plan on doing something else with my SparkFun windfall tomorrow.

Starters:  Peruse www.cnczone.com/ specifically the 'product reviews' section to figure out what works well for who.
www.diycnc.co.uk/  <<also invaluable resources for figuring out what connects to what - with specific plans available.  They even sell circuit boards, software, and motors.

"specifically with sparkfun parts" - that would be tough - essentially you need the mechanical parts - gantry, mounts, etc.
Motors - depends on the torque requirements of your project
Stepper Drivers
Stepper controllers (sometimes integrated with drivers)
The motors + drivers must be designed for one another - homopolar v. dipole, etc.

If you purchase a pre-built stepper controller (does the logic for the instructions and converts to stepper motor electrical signals) and driver (converts the stepper signals to high-power current signals for the motors) -- then you shouldn't have to flash anything - it should be ready to plug and play.

"which motor to use" - depends on the gearing/etc.  The motors either connect to the moving parts via chain/toothed pully drive, a worm screw or both.  'move 5 pounds of material' - again depends on the gearing.  If you chain-drive a worm screw with a high gear ratio, you'll have huge torque and low speed.

Software:  Lots of free software, lots of -pay- software.  refer to diycnc for more 'pro' info.www.diycnc.co.uk/html/beginners.html