BLTouch working

rlhotrodding

I just wanted to thank everyone for their help on the Bltouch.

I just got it installed and working great. Just something that I discovered during setup, watch out for the config override file.
It seems that it was turning heater 3 back to heater status instead of servo.

claustro

Anyone can confirm this wiring?
I read the wiki and it say to connect only 4 wires coming from bltouch isn't the 3 wires gnd connected?

BLTOUCH DUETWIFI

2wires cable
GND –----------Z probe GND
OUT--------------Z probe IN

3wires cable
+5V–------------+5 (pin1)
GND--------------???????
Control----------Heater3 (pin8)

dc42

Perhaps the ground should be connected to pin 2 of the expansion connector? I don't have a BLtouch, so perhaps someone else can confirm this.

iDevelo

@dc42:

Perhaps the ground should be connected to pin 2 of the expansion connector? I don't have a BLtouch, so perhaps someone else can confirm this.

Correct.

dc42

Thanks, I've updated the wiki.

HenrikM

That wiring is correct.
My bltouch is working perfect and i tried a extreme bed compensation with 1.5 mm high on one side and 1.5 mm low on other side and i got a Perfect first layer

BUT is there a code or something so you can "fade" out the compensation. that compensation makes the Z move around and can make ugly prints.

I had that on marlin with my mks board. 3mm was the compensation Then it dont compensate anymore and the print is level.
I have not tried that gcode that fades out in Marlin on my Duet. And i am not on my computer now so i cant see what that gcode is.

iDevelo

@HenrikM:

That wiring is correct.
My bltouch is working perfect and i tried a extreme bed compensation with 1.5 mm high on one side and 1.5 mm low on other side and i got a Perfect first layer

BUT is there a code or something so you can "fade" out the compensation. that compensation makes the Z move around and can make ugly prints.

I had that on marlin with my mks board. 3mm was the compensation Then it dont compensate anymore and the print is level.
I have not tried that gcode that fades out in Marlin on my Duet. And i am not on my computer now so i cant see what that gcode is.

Sure is M376 http://reprap.org/wiki/G-code#M376:_Set_bed_compensation_taper

HenrikM

Great! Thanks. Will try it later

toshi

Hello,
I wirred my Bltouch yesterday thanks to this thread, it's the new version with something to cut for 3.3V output. I can extend, retract, and simulate the bed contact with my finger with no limit.
But, there is always a problem =), When I launch a G32 with the following code (grid or points), the fourth point is always skipped with the error : ''Error: Z probe already triggered at start of probing move".
Do you have an idea ?

Config:

M558 P5 X0 Y0 Z5 H10 F200 T5000
M307 H3 A-1 C-1 D-1
M574 E0 S0
G31 X-30 Y-5 Z3.15 P25

Bed:

M280 P3 S10 I1
G4 P50

;**Mesh bed leveling
;G28 Z
;M557 X10:190 Y10:190 S36
;G29 S0

;**Point bed leveling
G30 P0 X-12 Y12 Z-99999
G30 P1 X-12 Y190 Z-99999
G30 P2 X170 Y190 Z-99999
G30 P3 X170 Y12 Z-99999 S0

G4 P50
M280 P3 S90 I1

ThePigSlayer

Toshi, you should probably decrease your trigger height. 3.15 is an awfully big trigger height, and since your dive height is only 5 (in m558), your z axis only goes up from 3.15 to 5mm, which is too short of a z-lift after each probe, which makes the probe report that it is already trigger before the travel move.

Your BL touch pin (the very tip) should be 2mm above the tip of your nozzle when retracted, which gives most people a trigger height of around 1.5mm. Your dive height of 5mm is normal, so either you need adjust your mount so you can lower your trigger height (by mounting the probe higher), or you miscalculated your trigger height. 3.15mm would be dangerously close to the height of the nozzle, and could catch during prints, so I think that it is more likely that you made a mistake when calculating the trigger height.

toshi

Thanks for you advises, I just finish to redesign my x carriage with 2.1mm différence between probe triggered and nozzle (tested), this program was with the initial mount, not optimized but worked. The issue was a wired cut inside the isolation thus a default.
Now it's working and perfect, maybe tune the speed and hight to have a better repetability. Some times at least 1 point is wrong and the 1rst layer too.

drmaestro

Hi,

Would it be ok if I used 270 ohms or 220 ohms as resistor, as I don't have 240 ohms.

Thanks

Sniffle

@drmaestro:

Hi,

Would it be ok if I used 270 ohms or 220 ohms as resistor, as I don't have 240 ohms.

Thanks

I would pull out a meter and test each of them since they have +-5%

If you have 4 1kohm resistors you can run them in parallel and get ~250ohms. again if you have something close meter them and use the closest to 240ohms

claustro

I am trying to setup bltouch and auto bed compensation
I added at config.g
[c];*** BLTouch
M307 H3 A-1 C-1 D-1
M558 P5 X0 Y0 Z1 H3 F200 T5000
G31 P100 X0 Y-20 Z2[/c]

and

[c]M557 X10:290 Y10:290 S70[/c]

Checked the trigger height as described in the wiki but now I am lost.
Where to put G29 command ? Should I use a bed.g config file? where I setup the probing sequence?

Also
I am trying to home the axis using bl touch
X and Y home correctly but I can't homing Z axis 'cos bltouch don't deploy during the procedure ( it deploy correctly if I launch the deploy command through console)
My endstop line in config.g is this
[c]M574 X1 Y2 Z0 S0[/c]
Iam using makerboat endstop on x and y and bltouch on z
Thank you

claustro

Is there anyone who can help me ? I am stuck

dc42

Homing Z using a Z probe is done using a G30 command. See https://duet3d.com/wiki/Configuring_RepRapFirmware_for_a_Cartesian_printer#Homing_files. To use a deployable Z probe, you need to ensure that you have set up the deployprobe.g and retractprobe.g files correctly for your probe, then in homez.g and homeall.g put M401 before the G30 command and M402 after it.

If you want to use mesh bed compensation then I suggest you put these commands in bed.g:

M401
G29
M402

HTH David

claustro

I am missing some basic information for understand how all the macro interact I reach this results simply copying some posted configuration but I don't understand how the firmware works
When I launch a print, how can I practically run a bed leveling routine and bed compensation?

I understand from the wiki there are 2 bed leveling system
G29 and G32 ( G29 is better for a core xy) so I went for G29 .
I have to use M557 command but where? I made a macro with this inside
[c]G91
G1 Z6 F200
G90
M98 Pdeployprobe.g
G29 S2
M557 X30:270 Y30:270 S60
G29
M98 Pretractprobe.g[/c]
and I can run it with G29 so I understand I could simply put G28 and then G29 in the start script in the slicer program , is that right?

What if I would use a simply 5 points bed leveling using something like this
[c]G30 P0 X50 Y50 Z-99999
G30 P1 X50 Y250 Z-99999
G30 P2 X250 Y250 Z-99999
G30 P3 X250 Y50 Z-99999
G30 P4 X150 Y150 Z-99999 S0
[/c]
where I should place this commands and How I should run it?

Hope You'll excuse me for such dumb questions but I always used Marlin based printer till now
Thank you very much

dc42

Have you read https://duet3d.com/wiki/Using_mesh_bed_compensation ?

You can put the M557 command in config.g assuming that you always want to probe the same bed area. Or it can go in the same file as the G29 command.

Your mesh bed levelling macro looks ok but the G29 S2 line is not needed because the height map is automatically cleared at the start of the other G29 command.

Your 5 point probing sequence also looks good, but of course you need to deploy the probe at the start and retract it at the end.

You could put either sequence in your bed.g file so that you can invoke it with G32.

claustro

@dc42:

Have you read https://duet3d.com/wiki/Using_mesh_bed_compensation ?

You can put the M557 command in config.g assuming that you always want to probe the same bed area. Or it can go in the same file as the G29 command.

Your mesh bed levelling macro looks ok but the G29 S2 line is not needed because the height map is automatically cleared at the start of the other G29 command.

Your 5 point probing sequence also looks good, but of course you need to deploy the probe at the start and retract it at the end.

You could put either sequence in your bed.g file so that you can invoke it with G32.

Thank you for all your patience and assistance.

Yes I read that part about 30 times Maybe I am missing some basic concept.
This is the part I can't understand

You can put the M557 command in config.g assuming that you always want to probe the same bed area. Or it can go in the same file as the G29 command.
You could put either sequence in your bed.g file so that you can invoke it with G32

If I understand correctly G29–> mesh bed levelling G32-->Probing at fixed points But I am missing the practical differences between this 2 commands.
if I'd put all the 2 sequences in bed.g with G29 command will be executed the mesh levelling instead with G32 will be executed the 5 points leveling is that correct?
-When I run a G29 command what config files are read by the board? And when I run a G32? Always look in bed.g if present?
How bed.g Config.g and a Macro interact?
You said that putting the M557 command in config.h will be tested always the same area, Do you mean that having differents macros for bed levelling I can starts it in many ways following may needs? How can I test 2 different pattern mesh map using G29 command? How can coexist 2 M557 command ? Using 2 differents macros?

I have another problem , when I home the Z probe seems to work perfectly, the printer register the touch point and the home Z button become blue . The problem is the probe that after touching the bed with the pin it start flashing and I have to reset it manually https://www.youtube.com/watch?v=eq2wTy3-kxA
this is my homing routine

[c]G91 ; relative mode
G1 Z4 F200 ; raise head 4mm to ensure it is above the Z probe trigger height
G90 ; back to absolute mode
M98 Pdeployprobe.g
G1 X150 Y150 F2000 ; put head over the centre of the bed, or wherever you want to probe
G30 ; lower head, stop when probe triggered and set Z to trigger height[/c]

Hope you'll be able to understand my very mad English

dc42

There are two sorts of bed compensation you can do:

1. Mesh levelling, using M557 to define the grid and G29 S0 (or just G29) to probe it. The height map is saved to a file, the default filename is heightmap.csv. You can also load a previously-generated height map using G29 S1.

2. Bed probing using a sequence of G30 commands. On Delta printers this does auto calibration. On Cartesian printers it is an older way of doing bed compensation, provided for backwards compatibility with older firmware that didn't support mesh levelling.

The G32 command simply runs the bed.g file.

On a Cartesian printer, you can use either mesh levelling (G29) or G30 probing, not both. I recommend mesh levelling. So I suggest you put your mesh levelling script in bed.g.

I'll leave it for someone who has a BLTouch to help you with your BLTouch issue.

HTH David