"Racks" VS "ball screw"

[C.AlveSilva]

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 use xx axis ball screws instead of racks (the racks in the place of the ball screws, put the engine in the middle xx 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, it is 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.

Sorry for my English...

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__________________
Atentamente

CarloSilva

[backyard_cnc]

Hello,

My name is Carlos and I'm form Portugal.

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

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

Thanks.

Sorry for my English...

--

__________________
Atentamente

CarloSilva

Carlos,

Many industrial and heavy duty router tables use RACK drives and they are very accurate and very fast. Choice depends on overall machine design and your budget
I have a SHOPBOT table and it uses rack drive on all 3 axis. Seems to work very well to me.

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