Re: CNC Router belt drive

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "wgaybba" <wgaybba@y...> wrote:

>
> Hi
>
> I'm planning on building a cnc router. Instead of having expensive
> screw drives, could I use a timing belt drive for the three axis. How
> will this drive compare to a screw? Can a belt drive lock like a screw?
>
> Thanks
> Wayne
>

There have been a lot of tables built with belt drives. You have a
choice of a continuous belt with a drive motor on one end and an idler
pulley on the other or an open piece of belt attached at the ends with
the motor on the gantry and the belt looped/around (>180 deg warp)
with idler bearings keeping tension and the wrap (kinda like a 16mm
projector mechanism (:-))

The belt drive of either style will not "lock" if the motors are not
under power. This can be an advantage as well as a disadvantage. For
static loads (horz) it affords a way for you to manually move the load
if it's ever required. If power is applied to the motors (stepper or
servo) the drive electronics will "lock" the motor and the load.

leadscrew drives work on short or loaded (verticle) loads. It's not
unusual to see a screw drive Z and rack & pinion or toothed belt drive
X & Y.