Backlash compensation

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Christian Wahl
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Backlash compensation

Post by Christian Wahl »

Hello

Is it possible to compensate backlash in just one direction? negative or positive Z direction
I want to mount steppermotor to the quillfeed on my mill and got backlash just in one direction because of springload/tention on the quill feed axel.
I know it is not the best solution, but i will mount Z feed on the knee at a lather stadium.
Btw it is a Bridgeport j-head mill

BR Christian
Bridgeport J-head retrofit
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tblough
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Re: Backlash compensation

Post by tblough »

Yup. Backlash tables have independent values for positive and negative directions.
Cheers,

Tom
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Muzzer
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Re: Backlash compensation

Post by Muzzer »

Thinking about the physics of this situation, presumably the effect is not backlash as such - more likely to be either stiction and/or elastic behaviour. Interesting to understand how backlash would be different in 2 directions.....
Nigelo
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Re: Backlash compensation

Post by Nigelo »

If you intend putting the quill under stepper powered axis control, surely you no longer need a strong spring return as the stepper will lock the quill in any position when at rest. This renders the return spring redundant and the quill may or may not be to one side of the lash. In that case, adjust the spring tension to achieve approx neutral buoyancy. You can and should then set the backlash in the conventional way

Hope this helps
"You can lead a horse to water but you cannot force it to drink"
Hope this helps
Nigel
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