Re: Re: X-Y Table, Rotary Table for CNC INFO

>    From: "ballendo <ballendo@...>" <ballendo@...>
> Subject: Re: X-Y Table, Rotary Table for CNC INFO

<s>

> Think scissor lift table. A couple of accurately placed pivots; ONE
> screw, lots of force. Problem: Stability in the direction perp. to
> the scissor. Fix that with a vertical guidepost (or two. Note that
> these DON'T need to be heavy duty linear motion component quality;
> they are just keeping the structure stable in one axis(resisting only
> side loads).

With a scissor you will need to be a bit careful where you place the
screw. The usual place is in the middle between pivot arms and
perpendicular to the motion. Many car jacks are made this way. With
something like this, z motion would NOT be linearly related to rotation
of the screw.

Ray