1 Topic by labguy

  • labguy
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  • Registered: 2013-06-15
  • Posts: 14

Topic: SD2 Z-axis cumulative error.

Hello,

My prints have a cumulative error on the z-axis that makes them bigger the taller they are.

For instance, if I print an object that is only 10mm high, the z-dimension will be about 10.1mm. If I print the object 70mm, I will see about 72.5mm. Some notes:

(1) Bed is leveled.
(2) I've calibrated the X, Y, and Z to within 0.1mm using a calibration print.
(3) Using RH to slice and print.
(4) Occurs with all prints, filament, etc.

Is there any way to reduce this error so larger prints are more accurate in the z-direction? Some ideas:

(1) Add anti-backlash nut to Z?
(2) Steps per mm on Z should be whole number (heard that somewhere)?

Thank you for the help.


Jeff

2 Reply by IanJohnson

  • IanJohnson
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  • Registered: 2012-08-07
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Re: SD2 Z-axis cumulative error.

It might have more to do with the object height not being evenly divisible by the layer height.  Rather than leaving the first layer at .3, maybe make it .3 + an amount to compensate for the rounding.

3 Reply by wardjr

  • wardjr
  • wardjr
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  • Registered: 2013-06-10
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Re: SD2 Z-axis cumulative error.

I won't claim to understand the calculation but I read somewhere on the forum that using .2963mm instead of .3 helps with that.  So I changed it and the problem went away I have been printing using that setting ever since with no problems.
I can't locate the post right now or I'd link to it.  There was a whole table of different settings you could use.

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