G32 command showing absurd results!

yatinsd

I have run the duet board for the first time and it is showing a bulged bed but i have a glass bed which i think has lesser possibility of this much error. kindly suggest ?

Dr_Ju_Ju

what are you sing for a probe ? and how is it configured ?

denke

Probably your "delta radius" is set too large. Also check "diagonal rod length", and "steps/mm"

Danal

An overall, symmetric, "Dip" or "Dome" indicates diagonal rod length or radius is wrong, in M665.

YOU must set M665 L (rod length). Carefully measure "joint center to joint center", or if you have Haydn Huntly rods, this is what is marked on the label.

Then run G32 a couple of times, saving with M500.

Only then try bed mesh again.

yatinsd

@denke what do you mean by steps.mm? i have checked the other 2! @Danal i have done g32 almost 5-10 times but no use still this graph is coming! @Dr_Ju_Ju i am using a microswitch for probe it is in always high mode!

Danal

When you run G32, it should produce a message that shows "Deviation" at the end. It appears in the console. What does that say?
Please post your config_override.g
What kind of printer, and specifically, what kind of diagonal rods do you have (where did they come from) and what is their length?

yatinsd

@Danal after g32 it didnt show anything on the panel! here is the override file:
; This is a system-generated file - do not edit
; Delta parameters
M665 L272.000 R120.000 H346.190 B100.0 X0.000 Y0.000 Z0.000
M666 X0.000 Y0.000 Z0.000 A0.00 B0.00
; Heater model parameters
M307 H0 A90.0 C700.0 D10.0 S1.00 B1
M307 H1 A340.0 C140.0 D5.5 S1.00 B0
M307 H2 A340.0 C140.0 D5.5 S1.00 B0
M307 H3 A340.0 C140.0 D5.5 S1.00 B0
M307 H4 A340.0 C140.0 D5.5 S1.00 B0
M307 H5 A340.0 C140.0 D5.5 S1.00 B0
M307 H6 A340.0 C140.0 D5.5 S1.00 B0
M307 H7 A340.0 C140.0 D5.5 S1.00 B0
; Z probe parameters
G31 T1 P500 X0.0 Y0.0 Z0.70
G31 T3 P500 X0.0 Y0.0 Z0.70
G31 T4 P600 X0.0 Y0.0 Z-0.79
Its an flsun delta printer with rod length 272mm though they claimed 267mm when i checked it was 272mm made with rod end bearings as its ends!

yatinsd

i have noticed one peculiar thing that the while i change the x or y coordinate its not able maintain its z though it shows the same but its isn't! I have checked thoroughly with a vernier caliper! Dimensions of the rod and radius i have thoroughly checked , its almost the same no error more than 1-1.5mm. what to do of this?

Danal

To verify a basic: The rods are 272 "joint center to joint center". Meaning, if they have ball links, this is to the center of the hole at each end.

Correct?

We are asking to verify these things because your symptoms say the M665 L or R is off. Or both. L is the easiest to measure, to my question above. The replacement rods for this printer sold by FLSUN claim to be 280, and the user comments on that listing state that 280 is wrong, they are 230. I also found a guy who claims to have working Marlin firmware, set to 218.

So... 280, 272, 267, 230, 218, which is correct, measured "hole to hole"?

Danal

@yatinsd said in G32 command showing absurd results!:

i have noticed one peculiar thing that the while i change the x or y coordinate its not able maintain its z

This is exactly what happens when L or R is incorrect. And the mesh bed level map is the "inverse" of what you are seeing as Z changes.

Until we get this corrected, nothing else will really work...

Danal

alt text

"Diagonal Rod Length" (hole center to hole center) is M665 L

"Horizontal Radius when Centered" is M665 R

From what you are seeing, one of these two is incorrect.

.

P.S. "Printer Radius" is not directly used by Duet RepRap firmware.

denke

@yatinsd
Steps/mm is the amount of stepper steps needed to move a tower pulley 1mm.

I suggest, that you command your printer to move (Z) up or down 100mm, and measure if the actual movement was 100mm.

Probably only 3 things can mess up a delta the exact way you described: Steps/mm, and as @Danial said M665 L and R

yatinsd

@denke its the step/mm that is at error! how to tune it?

yatinsd

can this be called fine?

denke

@yatinsd
M92 X100 Y100 Z100 E130 ; Set steps per mm

if all three (x,y,z) steppers use the same tooth count pulley, and the steppers all are the same type (for eg. 1.8 deg or 0.9deg per step) then the M92 X Y and Z values should be equal

After this is corrected then you can move on to the other two factor, the delta radius and diagonal rod length.