Re: [CAD_CAM_EDM_DRO] Re: Servo controllers for table top machines.

On Mon, 18 Dec 2006 00:53:55 -0000, you wrote:

>It sounds like a micro stepping system will provide the same
>repeatability and precision as a Servo system like the one from
>camtronics. Then why are there so many companies saying that servo
>will be a better system?

Because they want to sell you a more expensive servo system.

>The servo system from Techno bolts the servo motors directly to the
>ball screw with out a reduction pulley. The only thing is they have a
>brake on the Z-axis.

Probably because the servo can't hold the weight of the Z axis using the
pitch screw ratio to weight and cutting forces.

There are stepper machines out there also that use a brake on the Z,
always seems to me as an afterthought or fudge to circumvent a poor
original design.

If the pitch of the screw, axis weight and choice of drive is correct,
there should be no need for a brake,

Steve Blackmore
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