Set up three Z-axis location - M671
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Hey guys,
Set up three Z-axis location - M671- in RRF3 on Duet 3 MB6HC:
Which coordinates should I enter? The real ones of the leadscrews (A) or the ones where the bed actually rests (B)?
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In theory the B locations are the best.
But during testing I have tried both A and B locations with equivalent results.
Frederick
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If it's a properly designed kinematic mount where the center of rotation is at the contact point between the mount and bed, use B. If it's a more rigid bed mount use A because the point of rotation is likely going to be closer to the point of force.
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Yes, it is a kinematic mount with ball screws. According to my logic, I wanted to use the "B" position too. Many thanks for your help
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@bernie-mix said in Set up three Z-axis location - M671:
Yes, it is a kinematic mount with ball screws. According to my logic, I wanted to use the "B" position too. Many thanks for your help
What rests on the balls?
On my printer the left and right are v-groves and the rear is a simple spherical recess.
Thanks.
Frederick
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At the rear is a magnetic spherical recess, front right is magnetic v-groves (45° to X and Y axis) and front left a a plane round magnet
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@bernie-mix said in Set up three Z-axis location - M671:
At the rear is a magnetic spherical recess, front right is magnetic v-groves (45° to X and Y axis) and front left a a plane round magnet
How did you chose that arrangement? I found that the two front points could use the same approach.
Thanks.
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@fcwilt
In my opinion, this is the only way the bed can expand in all directions without rotating around the spherical recess -
@bernie-mix said in Set up three Z-axis location - M671:
@fcwilt
In my opinion, this is the only way the bed can expand in all directions without rotating around the spherical recessAh... So the balls are lifting the heated bed itself? If so I can understand your arrangement.
Thanks.
Frederick
