Z moving twice distance - Was working - now it's double
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I don't have an override at all.
I just confirmed that it happens even if i raise Z before I home.homeall.g
G91 ; relative mode G1 S2 Z10 F200 ; hop Z up 10 G1 S1 X-299 Y-299 F3000 ; move up to 240mm in the -X and -Y directions until the homing switches are triggered G1 S2 X4 Y4 F600 ; move slowly 6mm in +X and +Y directions G1 S1 X-10 Y-10 ; move up to 10mm in the -X and -Y directions until the homing switches are triggered G90 ; back to absolute mode G29 S2 ; disable mesh compensation G1 X143.9 Y147.3 F2000 ; put probe at center of bed G30 ; home z G1 X-10 Y240 Z20 ; move tool out of way G4 P1000 ; dwell a sec G29 S1 ; enable compensation -
@RedMachine Just a quick test: does Z scale properly if you set the steps/mm to 400 in your config.g?
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@infiniteloop
Yes, I just changed Z to 400 steps/mm it and it does appear to be correct with just a quick caliper check.Am I wrong in thinking that a 8mm trap and 1.8 steppers at x16 should be 800 steps / mm?
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@RedMachine said in Z moving twice distance - Was working - now it's double:
Am I wrong in thinking that a 8mm trap and 1.8 steppers at x16 should be 800 steps / mm?
Counter-question: how could your printer ever work with 800 steps - you said he did that happily for three weeks? The only reason I can imagine is that you had a second M92 (with Z400.00) in your config before you took some spring-cleaning action
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@RedMachine said in Z moving twice distance - Was working - now it's double:
@infiniteloop
Yes, I just changed Z to 400 steps/mm it and it does appear to be correct with just a quick caliper check.Am I wrong in thinking that a 8mm trap and 1.8 steppers at x16 should be 800 steps / mm?
It depends on the lead of the screw which is how far a nut will travel in one revolution. This is a function of the pitch and the number of thread (starts). So if the pitch is 1mm and it's a 4 start thread, then the lead is 4mm. A 1.8 degree stepper has 200 full steps per revolution. So 200 full steps will move a nut 4mm and from that we can say that 50 full steps gives 1mm of linear movement. 50 full steps X 16 microsteps = 800 which is what you have. But if the pitch is 2mm then the lead is 8 mm giving 25 full steps per mm = 400 microsteps at 16X.
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For posterity:
Z_steps_per_mm = (motor_steps_per_rev * driver_microstep) / screw_leadDoes not take any gear ratio into account.
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@Phaedrux I'm so glad you used the term "lead" rather than"pitch" (it's a pet hate of mine)
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@deckingman It's the least I could do.
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Which does indeed = 400. So I either, suffering from some brain problems, changed it to 800 and assumed it was like that all along or did have something overriding it that I inadvertently changed. Not sure which is the better scenario.
Either way, thanks for your patience.
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@RedMachine No worries - you got it fixed which is the main thing.
