another question about mesh levelling probing 3.4.5
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Hello. Take a look please at my config files (in order to be short I post only the important lines. I dont know if it is a problem or not, but I still have doubts about where it is correct to do bed probing (ht ecorrect position). Specially because today, I have notice that seems that in 3.4.5 (or at least I have noticed it in this version after update), sometme the z probe offset is automatically applied to the probing coodinates.
My bed is 350X350mm, so the center should be X175 and Y175 . My Z probe offsets are X-7.5 Y-27 . If you see my bed.g I probe the center of the bed (manually applying the offset so the Z probe is sensing the real geometrix center of the bed) and that works ok. But then if you see my 2 points for levelling tilt of the bed, Im still using a Y value of 202, BUT im seeing that the probing is done on Y229, so the Y offset is being automatically applied. Is this correct?Bed.g
M561 ; clear any bed transform
G28 ; home
G1 X182.5 Y202 F2000
G30
G30 P0 X10 Y202 Z-99999 ; probe near left leadscrew
G30 P1 X345 Y202 Z-99999 S2 ; probe near right leadscrew and calibrate 2 motors
M400
G4 S5
G1 X182.5 Y202 F2000
G30
G30 P0 X10 Y202 Z-99999 ; probe near left leadscrew
G30 P1 X345 Y202 Z-99999 S2 ; probe near right leadscrew and calibrate 2 motors
M400
G28 Z0My Homez.g file
M564 H0
T0 P0
G91
G1 Z5
M564 H1
G90
G1 X182.5 Y202 F5000
G30 -
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@Phaedrux the routine I have posted is correct? because what I phisically see is that probing on the sides are done in a different line than the central prbing (central s done on Y202 and on the sides is done on Y229)
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When you use G30 by itself, you must first position the nozzle such that the probe is where you want it taking the offset into account.
When you use G30 with a P# positional point, the point is where you want the probe to go and the offset is calculated for you.
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@Phaedrux but that is what at least for me is not clear regarding how the coordiantes work:
G30 P# measures a point. in my case no probing point is coincident with the printbed center. Following the recomendation on dics, I should probe the center and the 2 points nearest to the leadscrews of my printbed.
in my config Improbing P0 and P1 (X10 Y202 and X345 Y202) and in those points probing is bein done on Y229, so offset is being aplied. So to be right I should change that and command hte G30 to be done on X10 Y175 and X345 Y175, so the offset is aplied
and here my question arises: the center of the bed probing, where I manually send the probe to X182.5 Y202... Im manually aplying the offset, the firmware thinks it is probing X175 Y175 ot thinks it is probing 182.5 Y202 ? -
It still knows where the probe is. So if you send the nozzle to the center of the bed, it knows the probe offset and it knows where it's probing. If you want to probe the center of the bed, move the nozzle such that the probe is at the center.
