Re: [CAD_CAM_EDM_DRO] Re: How to Make a Simple CNC Machine

kleinbauer@... wrote:

> Hi Alvaro,
> Thanks for the kind words. My booklet has a over 50 computer
>
> drawing....others plans don't even come close. Who needs a $150
> leadscrew when a $2 piece of 1/4-20 threaded rod will work.

Well, even on a machine as small as the one you describe, there may
be significant bowing of the leadscrew (unless it is placed under
considerable
tension). Do you have something to eliminate backlash?

What is the overall accuracy of the 1/4-20 rod?

> I use a
> one inch piece of rubber tubing to couple the motor to the threaded
> rod.

How rigid in torsion is that rubber tubing? Or, do you really use some
stiff
plastic tubing? That might be pretty good, but if you really use
RUBBER, it
might allow quite a few steps worth of twist to develop between the
motor
and leadscrew.

Jon