Duet 2 Wifi + BLtouch issues on Ender 5 pro

peter247

@alxndr O.K you have a ender 5 pro , So how or should I say where does to home , Right ( X max ) , Back ( Y max ) , Z Bltouch ?

If so I can more or less give you my homing macros , but mine is for a 350x350 bed , so the hitting the centre of the bed will need to be changed.

alxndr

@peter247 thats correct...mine homes at the back (y max) right (x max) when im facing the front. as for the z, its the end stop right now...bltouch doesnt deploy yet cause i didnt get to change it yet as im at work.

peter247

@alxndr

change 355 to 225 , 5mm more than the max

; homex.g
; called to home the X axis
;
; generated by RepRapFirmware Configuration Tool v3.1.3 on Sat Jun 20 2020 16:28:00 GMT+0100 (British Summer Time)
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 X 355 F3000 ; move quickly to X axis endstop and stop there (first pass)
;G1 H2 X-5 F6000    ; go back a few mm
;G1 H1 X 355 F240  ; move slowly to X axis endstop once more (second pass)
G1 H2 Z-5 F6000   ; lower Z again
G90               ; absolute positioning

; homey.g
; called to home the Y axis
;
; generated by RepRapFirmware Configuration Tool v3.1.3 on Sat Jun 20 2020 16:28:00 GMT+0100 (British Summer Time)
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 Y 355 F3000 ; move quickly to Y axis endstop and stop there (first pass)
;G1 H2 Y-5 F6000    ; go back a few mm
;G1 H1 Y355 F240  ; move slowly to Y axis endstop once more (second pass)
G1 H2 Z-5 F6000   ; lower Z again
G90               ; absolute positioning

; homez.g
; called to home the Z axis
;
;G28 XY
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 X 355 F3000 ; move quickly to X axis endstop and stop there (first pass)
G1 H1 Y 355 F3000 ; move quickly to Y axis endstop and stop there (first pass)
;G1 H2 Z-5 F6000   ; lower Z again
G90               ; absolute positioning

G1 X220 Y175 F4000 ; Move probe to middle of bed
G30

note is the same as homez.g

; homeall.g
; called to home all axes
;
;G28 XY
G91               ; relative positioning
G1 H2 Z5 F6000    ; lift Z relative to current position
G1 H1 X 355 F3000 ; move quickly to X axis endstop and stop there (first pass)
G1 H1 Y 355 F3000 ; move quickly to Y axis endstop and stop there (first pass)
;G1 H2 Z-5 F6000   ; lower Z again
G90               ; absolute positioning

G1 X220 Y175 F4000 ; Move probe to middle of bed
G30

X220 is the centre of my bed , 350 / 2 + 45 offset

alxndr

@peter247 wow thank you!

a few questions....my x and y both have a value of 220....why do the values need to be 5mm more? is it so that it backs up afterwards? like the amount of distance to press into the switch and back out?

also, for the z im a little confused...how do i find the value for that?

and lastly, the bed is x220 and y220 so would the center be 110? the nozzle seems to be perfectly in the center at x110 y110....and the z at that point id have to figure out i guess?

peter247

you don't need to set the value that high , so 220 or less will do , it is maximum travel before it stops and say I'm homed without hitting the switch.

no 110 is not the centre of the bed for the bltouch it is the centre of the bed for the nozzle , so the centre is 110 plus the offset of 45mm X ( 155mm for the bltouch ) and 110 + 4mm Y so just go at half .

Hope that makes sense to you now ?.

how do you find the off set ?
first set the value in G31 Z to zero , Home and see if it home but is off the bed , then slowly increase the value of Z until it hits the bed when Z say Z say 0.0mm

MAKE SURE IT WILL HOME FIRST , THAT IS THE IMPORTANT PART.

o.k my system all the motor are backward ? , make sure to motor direction is correct too.

alxndr

@peter247 first part makes sense! thank you. What did you mean by "just go at half?'

X be 155 and Y would be 114 because of the offset of the bltouch?

as for the z offset, how would i set the value of G31 Z to 0? just input the line G31 Z0 ?

and then you say to check if it homes. But im pretty sure it pushes up onto my nozzle if i home z. I dont get the last part when you say "...then slowly increase the value of Z until it hits the bed when Z say Z say 0.0mm"

My motors seem correct....not sure if they are backwards...but they home at the back right which is what it was with the stock motherboard...

peter247

@alxndr My motors seem correct....

Two wrongs can make a right , eg if you are homing in the wrong
direction and your motor are in the wrong direction it will look right.

Look at your config file :
; Z-Probe
M558 P9 C"^zprobe.in" H5 F100 T2000 ;
M950 S0 C"exp.heater3" ; define GPIO/Servo pin index
M557 X0:220 Y0:220 S25 ; define mesh grid
G31 X-45 Y-4 Z3.737 ; <------------- just change this to Z0 ---------
M307 H3 A-1 C-1 D-1 ;

What I'm saying is get it to home with crashing into the bed , then you can find the true offset .

Have you changed the homing files ? and does m401 and m402 work ?

alxndr

@peter247 i havent had a chance to test m401 and m402 yet as im still at work. ill do those tests after work and get back to you! thanks so much for helping. im learning and progressing so much! ill reply back with my test results asap!

peter247

Going to bed soon I`m in the UK , so bits to check.

(1) See if m401 and m402 works
(2) You need to change all the homing files
(3) press home x then press the x micro-switch does it stop , PANIC if not
(4) press home y then press the y micro-switch does it stop, PANIC if not
(5) press home all and see which way the head goes now to home ( with your finger on the emergency stop), I think your motors direction is wrong x , y , z ) it is the M569 commands in the config.g
(6) get it to home all axis correct without the nozzle hitting to bed.

alxndr

@peter247 so homing z works fine now. ive got it all set up with the homey homex and homez and homeall....now im having a stupid little annoying issue......220 isnt the bed size? the bed size is actually 235!! wtf...creality advertises it as 220 but when i measure it, its actually 235!! do i need to change everything now?

Phaedrux

@alxndr said in Duet 2 Wifi + BLtouch issues on Ender 5 pro:

; Axis Limits
M208 X0 Y0 Z0 S1 ; set axis minima
M208 X220 Y220 Z300 S0 ; set axis maxima

You can change your axis limits with the M208 commands.

This may mean you need to change your M557 grid spacing a bit.

You also need to make sure that the homing moves in your homing files are long enough to hit the endstops if they are at the opposite end already.

You might find this series of guides helpful

https://duet3d.dozuki.com/Guide/Ender+3+Pro+and+Duet+Maestro+Guide+Part+3:+Commissioning/39

peter247

@alxndr the bed size is actually 235!! wtf

The 220 x 220 is the printable size !!
A cr10s pro says 300x300 , but the bed is 320x310
a ender 5 plus says 350x350 , but the bed is 370x377

if you print at 0:0 you can't print on fresh air so the bed is always bigger than the printable area.
When it X and Y homes is that under the bed , just check that all the printable area is under the bed .

droftarts

@alxndr I tend to use the P parameter rather than the S parameter with M557. This sets the number of points to probe, rather than the spacing between them. Then, if you change the probe area, it still probes the same number of points, evenly spaced, without having to calculate the probe spacing yourself. It's also quicker to change if you want to change the number of probe points in the mesh. So:
M557 X35:185 Y35:185 S50 (which probes X and Y at 35, 85, 135 and 185, so 4 points in each axis for a total of 16 points)
becomes:
M557 X35:185 Y35:185 P4
To increase or decrease the number of probe points, you just change the P parameter.

See https://duet3d.dozuki.com/Wiki/Gcode?revisionid=HEAD#Section_M557_Set_Z_probe_point_or_define_probing_grid

Ian

alxndr

@peter247 i just dont get something...if the physical bed is 235x235, why are my axis limits 220x220? I mean...dont i base my bed center off of the actual bed size? nowhere in the gcode shows the ACTUAL bed size of 235x235. Am i doing something wrong? because if i go from left to right, it goes from 0 to 220...

as for everything else, homing works and the bltouch works deploys and retracts properly! m401 and m402 confirmed working!!

what are the next steps? do i have to remove the lines for my z endstop?

alxndr

@droftarts this is great to know! thank you!

droftarts

@alxndr When you home X, then move to X0, is the nozzle on the edge of the bed? If it's over the bed, there will be some of the bed you cannot use. Same at the other end of the X axis, and for Y minimum and maximum. You can always adjust M208 to increase the axis limits, so long as the nozzle can physically reach the position.

If you home X, and X=0 is off the bed, you need to know how far it is to the edge of the bed. For example, if you jog the X axis 10mm for the nozzle to be over the bed, then you would set M208 X-10 S1. This tells the firmware where the bed is in relation to the X endstop. Then move the X to the far side of the bed (with X0 on the edge of the bed) to see the full X axis limit; this might be X240, but the nozzle is off the bed on the other side, but is on the edge at X235. So set M208 X235 S0. Repeat for the Y axis. This should give you the maximum printable area.

Use of M208 is explained more fully here: https://duet3d.dozuki.com/Wiki/Centering_the_bed_or_setting_the_bed_origin

Edit: when you are testing where the limits are, you may need to go beyond the current M208 limits. Send M564 S0 H0, which will allow moves outside the print volume and before axes are homed. Use carefully!

Ian

alxndr

@droftarts this is something ill have to check once i get home from work. I'm in EST time zone (Canada). So i'll only get to check this later today. thanks for the explanation. I dont fully understand but i do kind of understand lol i just dont see how the printer knows that the bed is 235 but only 220 is used. But ill test as you recommended and try to understand. I think it would be easier if i get to see it for myself.

peter247

@alxndr
o.k I'll have my go again at explaining it.

( my example thought experiment)

The maximum travel is 400mm , but the print area is only 300mm eg the size of the glass is 300mm , but the maximum distance between the left and right end stops is 400mm.
if it homed left or right it would be 100mm from edge of the glass , So you would need to add a offset which would add or subtract 100mm so 0mm and 300mm was over glass.
BUT I THINK in your case, when your print homes it is 10mm from the right edge of the printer and say "I'm homed and set to 220mm" , now if you do a G1 X0 this would move it 220mm to the left and now the nozzle would be 15mm from the left edge.
SO IT DEPEND ON how it is homed, is it about 10-15mm from the edge of the bed or over it ?

Phaedrux

@alxndr said in Duet 2 Wifi + BLtouch issues on Ender 5 pro:

i just dont see how the printer knows that the bed is 235 but only 220 is used.

Well it doesn't, but if the endstop is off the edge of the bed, and you want 0,0 to be the corner of the printable area, the difference in negative movement from 0,0 to the endstop is captured by setting the M208 minima to a negative value, as droftarts showed above.

Phaedrux

Bed Area.png

Visual aid. This shows the endstops coinciding with the printable area, but if the nozzle travels off the bed to hit tne endstop, that extra movement is captured by the negative M208 minima.