First router

[jedge]

I have been planing to build my own CNC for a while now, and I have made this CAD.


My plan is to use MDF for most of the parts, and for the linear bearings I will use roller bearings, and angle aluminum.

Lead screw - 10 - 1/2 inch acme screw (is this a good size or is it too large)
I was going to just going to use an acme nut to attach it, but I have read about anti backlash nuts. Are those necessary and how do they work?

How big of stepper motors do I need to drive this, and what system do yall suggest for controlling them?

I plan to use this with either a dremel, or a trim router.

I am relatively new to this, any help is appreciated.

[rmcdowellbbi]

1/2" Acme is a good size. Backlash is the play in a loose fitting screw. it prevents the gantry or table from moving when the direction is reversed for a short period of time.
Richmcd

[CarveOne]

1/2-10 ACME screws are correct for this size machine and you can find anti-backlash nuts at CNCrouterparts and DumpsterCNC. They use two different spring loaded methods of keeping the nut threads snug against the ACME screw threads at all times. A regular ACME nut or coupler will have a little built in clearance in order to allow for differences in the screw tolerances.

Highly recommended to use them on all axis.

CarveOne

[jedge]

Thanks, but how big of stepper motor will be necessary to drive the lead screws? Would 185 oz-in be enough, or do I need more?(I was looking at the Nema 23 motors)

Do yall have suggestions on control systems? I was looking at gecko controllers.

Thanks for the help

[CarveOne]

Thanks, but how big of stepper motor will be necessary to drive the lead screws? Would 185 oz-in be enough, or do I need more?(I was looking at the Nema 23 motors)

Do yall have suggestions on control systems? I was looking at gecko controllers.

Thanks for the help

The best controller for the money is the Gecko G540. The Gecko drives have a lot of features that are not offered in lower cost drives.

My guess is if your machine is roughly 2'x2' then 185 oz may be enough, but if it is 3'x3" or 4'x4' I would recommend 270 or 305 oz steppers. You haven't given any working size so far.

CarveOne

[jedge]

It willl be 3 by 3. So I should go with 270 oz in motors?
Thanks

[CarveOne]

It willl be 3 by 3. So I should go with 270 oz in motors?
Thanks

I would recommend the 270 or 305 oz steppers with a G540 driver board, but you don't need 425 oz steppers as they will only run slower. You should look at the package deal from cncroutertparts with pre-connectorized motors that are customized for the G540. Keling also has a G540 and motor package deal.

ger21 may have some other suggestions.

CarveOne

[ger21]

How much are you looking to spend here?

[jedge]

I want to try to keep it under $1000 but I might be able to spend more.