Advice for a machine and parts

[ennova]

Hello,

I have been saving up for a cnc router for a while now and I have a budget of roughly $4500 to put towards a new machine build. I'm asking for advice as where to best put that money to good use. This is a lot of money for me and I don't want to end up wasting it, I'm rather nervous as this is my first built etc. Anyways I'm looking for a cnc router table that will have the ability to cut aluminum, plastic and wood, while maintaining good accuracy and repeatability. I want my machine to be roughly 3'x3' or 4'x4' of actual work area and made out of 8020 with steel sides.

I am aiming to have my machine turn out to be similar to this one:
Ebay AD
Blurry Customs

I am planning to go with the Geckodrive G540 with Nema 23 stepper motors, however I was wondering if I should change it so a servo motor system since I'm wanting to machine aluminum parts etc and if so which system?

I am planning on buying a spindle such as this one:
Spindle
However as I understand it I'll need a new VFD to get it to work with Mach 3? If that is the case are there any that you can recommend me? Would the ones listed on blurrycustoms.com work? Also does anyone know of a good place for me to buy a mount to attach it to my Z-axis? I was thinking of getting a local machine shop to help me make my mount.

For linear rails and ballscrews, I was also going to buy those from linearmotionbearings2008 Would those be a bad investment, should I consider getting my rails from Glacern or somewhere else? I'm planning on using 2 ballscrews for the X-axis. I'm concerned that I'll end up with some backlash that will be hard to eliminate.

Also I understand there is a way for Mach 3 to be programed to work well with ballscrews when used in combination with a measurement device that measures any imperfections in the ballscrew. The name of the device is eluding me right now. (like a built in caliper or something?) I want to have those devices built into my table. Any recommended way of doing this?

Are there any pre-built z-axis out there that use ballscrews and not acme screws?

Thanks for your time to read my post. I would appreciate any and all advice anyone has to offer me. Thanks,
Ennova

P.S. When I browse posts now, it is in a backwards order of what I'm used to? (First post being the last post now). How do I fix this? It is really awkward for me to browse these forums now. It wasn't like this last week etc. It is really weird.

[Al_The_Man]

/URL]

P.S. When I browse posts now, it is in a backwards order of what I'm used to? (First post being the last post now). How do I fix this? It is really awkward for me to browse these forums now. It wasn't like this last week etc. It is really weird.

Go to quicklinks - edit options.
Al.

[ennova]

Thanks Al~ It is fixed!

[ahren]

As long as you get ball screws with a reasonably high pitch (0.2 inches / rev or more), a G540 based solution is a great way to power your machine. Servos really shine in applications where things are geared mechanically to run at higher RPM's. As long as you don't design your machine with a low pitch screw, they aren't really necessary, and won't get you much except the headache of tuning PID loops.

Blurry customs has a great machine. They use our steppers and cables with a G540 drive on most of their machines.

Best regards,

Ahren
www.cncrouterparts.com