Hello,

My name is Carlos and i'm form Portugal.

I want to built a CNC router to make 3D wooden molds.

I was thinking in the xx axis use racks instead of ball screws, (the racks in the place of the ball screws, put the xx motor in the middle of the yy axis and using a shaft with a pulley at each end).

In terms of accuracy, racks is worse than a ball screw??

I want the router to make molds, for it I need a lot of precision. (For this kind of work an error of 0.1 mm (0.0039 inches) is an huge error.)

Would you, please, give me your opinion about the racks?

Thanks.

P.S.: Sorry for my English...