[Flog]

First off, let me thank this forum for it's knowledge base, my interest has been greatly peaked by what I have read so far. Second, I'm a slow moving son of a gun, I like to make plans and learn about things, before I dive in. Oh well, on to the questions.

I've decided to go with cabinet plywood vice MDF due to it's weight and sensitivity t moisture. A good 5 to 7 ply 3/4" meet's my sensibilities on strength and moisture resistance.

For my first cnc, I'm looking strongly at 24" bearing bottom drawer slides for the x and y platforms with screw drives, both being on the base and the gantry holding the z only. Haven't figured out the method of linear motion for that yet. Fig 1 the genera layout, Fig 2 some 2" x 4" bracing around the edges (support for the upcoming gantry), Fig 3 a visual on how 2 offset pairs of 24" drawer slides allow 24"s of travel with 24"s of y-platform support.

Wood will be the carving medium, I don't think milling metal will be an interest, but stone (yes, I'm into lapidary too) may be. Yep I know that something along the lines of extruded aluminum platform will be needed, but I hope to gain enough experience in the wood phase to make stone a reality.

Anyway, I'm thinking of a 3 axis NEMA 23 280 inch/ounce system with as much freeware as is reasonable. I'm fairly competent with computers, having started in the days of Apple II and Commodore 16. The question for now is, are those sets seen on ebay, worth it? I'm looking at this specifically: 4Axis Nema 23 Stepper Motor 287oz-in & Driver board (TB6560)CNC Kit Top Selling 4Axis NEMA 23 Stepper Motor 287oz in Driver Board TB6560 CNC Kit | eBay

Bipolar stepper motors, what I got from a wiki, hmm, not so great? TB6560 driver board, no idea. Maybe a pointer to some reviews would help.

Well, thanks for listening, bye now

[ger21]

Personally, I'd never recommend any chinese kits on Ebay. They're cheap, but rarely any good. But if you have a tight budget, many people do use them.

Those appear to be 6 wire motors, which make them unipolar.
But they can be wired to a bipolar drive.
Neither unipolar nor bipolar is necessarily any better than the other.
You just need an appropriately size motor for the application.

[Flog]

Thanks ger21, every bit of knowledge helps. Yeah, for a first time project, going to keep it cheap. Gads, the amount of software needed is huge, cad, cam, controller. Definitely going to be a lot of learning.

[Devastator]

Drawer slides, that's not going to give much rigidity. The TB6560 boards are notorious crap. The hobbycnc ezdriver has been good to me and only costs $45 or so. Steppers I got were from Circuit Specialists - Simply Smarter Circuitry Since '71 for about $25 ea.

[SteveWill]

Here is a thread of the build I did and the mod I did http://www.cnczone.com/forums/diy-cn...ml#post1575098
The drivers I used are good and I have not had any problems with them.
Also there is a list of soft ware to look at.
I am using
Mach3 less than $200, You can use free for a few time to see if you like it.
Cambam free (Down rev (oldest) on their site. I will be upgrading to latest soon. less then $200
Punch viacad, you can get older version for around $40
I have had a lot of question about using the 1/2 all thread as being bad, but they seem to me to work well, I wonder if the smaller thread give problems.
Something I found in making my own CNC was anything that has any play in it was bad. so no play and the more ridged the better.
It was fun to do.