Adjusting Z-offset in config?
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This always confused me. I just used baby steps to adjust my first layer. -0.45.
My config has my Z-offset as Z2.18. So, do I add 0.45 + 2.18 or subtract 0.45-2.18?
My baby steps lowered the nozzle, but the z offset is the distance between the BL touch trigger and the nozzle. ?
Thanks.
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@westech said in Adjusting Z-offset in config?:
This always confused me. I just used baby steps to adjust my first layer. -0.45.
My config has my Z-offset as Z2.18. So, do I add 0.45 + 2.18 or subtract 0.45-2.18?
My baby steps lowered the nozzle, but the z offset is the distance between the BL touch trigger and the nozzle. ?
Thanks.
The Z Trigger Height parameter for the Z probe is the value that is assigned to the logical Z position when the probe triggers.
A BLTouch probe is going to be within a few mm's of the bed when it triggers but Z Trigger Height parameter could be set to 10,000 and the firmware would happily set the logical Z position to 10,000 - which is clearly nonsensical.
The firmware is "trusting" that the Z Trigger Height parameter is the correct value.
If when you jog to Z=0 and you end up not touching the bed the Z Trigger Height parameter is too small.
On the other hand if you run into the bed while jogging to Z=0 then the Z Trigger Height parameter is too large.
You take whatever the value is from baby-stepping and subtract it from Z Trigger Height parameter. Of course subtracting a negative number is the same as adding the absolute value of the negative number.
Frederick
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That answers the confusing part. I added 0.45 to 2.18 = 2.63. And that seemed to work. You have to disregard the negative number.
Thanks
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@westech said in Adjusting Z-offset in config?:
That answers the confusing part. I added 0.45 to 2.18 = 2.63. And that seemed to work. You have to disregard the negative number.
Thanks
Or you can always just subtract the actual number displayed by the baby-stepping, regardless of the sign of the value. The result will be correct.
Frederick
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@westech Increasing the Z offset gets it closer to the bed, decreasing is farther away. I added this as a comment the the G31, so I wouldn't forget.
