BLTouch working

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By Syko_Symatic 13 January 2017 16:46

Member · 31 comments

Thanks. That's good then! Yes a diagram would help but I understand it's early days. I have it setup currently on my Bigbox (Rumba) so looking forward to switching.

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By Syko_Symatic 15 January 2017 08:46

Member · 31 comments

If anyone could knock up a quick diagram of connecting the BLTOUCH to a duet wifi I would appreciate it. I am getting everything ready to change over on Saturday evening.

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By ThePigSlayer 16 January 2017 02:30

Member · 10 comments

I have set my BL Touch up, but I am having a lot of repeatability issues that I am hoping someone could help me with. I have followed all the instructions in this thread as best as I could. I am using the resistor, plugging into the z probe pins, pin 1 and 2 on the expansion, and heater3 pin. I have tried changing the trigger value a bit which didnt do anything. All my connections seem fine as they are crimped and the resistor is soldered.

Here are the results (just the Z coordinate) from four 5-point auto bed compensations that I did in a row, without the heated bed or anything turned on.

[ 0.000]   [-0.190]   [0.425]   [0.112]   [0.158]
[ 0.082]   [-0.170]   [0.540]   [0.503]   [0.285]
[ 0.010]   [-0.522]   [0.780]   [0.635]   [0.293]
[-0.122]   [-0.637]   [0.322]   [0.115]   [0.197]

As you can see there is a big difference between each new probe sequence. Here are some relevant config files and my bed file.

; BL Touch
M558 P5 X0 Y0 Z1 H4 F450 T4000 
G31 P25 X36 Y0 Z1.5

; Auto Bed Compensation
M561
M98 Pdeployprobe.g
; Probe the bed at 5 points
G30 P0 X15 Y15 H0 Z-99999
G30 P1 X15 Y175 H0 Z-99999
G30 P2 X185 Y175 H0 Z-99999
G30 P3 X185 Y15 H0 Z-99999
G30 P4 X100 Y100 H0 Z-99999 S
M98 Pretractprobe.g

Thanks in advance for any help.

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By (In)Sanity 16 January 2017 02:43

Member · 267 comments

Few things to check,

Make sure your config_override.g isn't changing the value of the G31 P25...command. 

I'm actually running G31 P1 (vs P25) and have been.   My theory is that the even shorter pulse detection gives the Z axis less time to move once triggered.   I've had really consistent results.    Granted if the z axis overshoots the same each time it shouldn't matter.  But still perhaps worth a try.

Edit:  Not that it matters but M401 can be used to call the deploy.g and M402 to call the retract.   Just a bit cleaner.

Jeff

Last edited by (In)Sanity (16 January 2017 02:44)


Duet WiFi Powered FFCP with E3D legends hotend system.  BLTouch grid leveling.

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By (In)Sanity 16 January 2017 02:46

Member · 267 comments

So your not wanting to run the grid based compensation ,   G29 ?


Duet WiFi Powered FFCP with E3D legends hotend system.  BLTouch grid leveling.

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By ThePigSlayer 16 January 2017 03:09

Member · 10 comments

I remember I used to have a config override file but after updating a few times it seems to have disappeared. Is this a problem?

I tried a lower trigger value but haven't had any better results. I also decreased my Z acceleration as it was set pretty high. Also ironically shortly after I posted, I set up a macro for grid compensation. The probe points produce different values each time.

Any other suggestions? Thanks a lot for the help. I read your previous post about M401/2, but just forgot to change it, thanks though!

Last edited by ThePigSlayer (16 January 2017 03:10)

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By (In)Sanity 16 January 2017 03:57

Member · 267 comments
ThePigSlayer wrote

I remember I used to have a config override file but after updating a few times it seems to have disappeared. Is this a problem?

I tried a lower trigger value but haven't had any better results. I also decreased my Z acceleration as it was set pretty high. Also ironically shortly after I posted, I set up a macro for grid compensation. The probe points produce different values each time.

Any other suggestions? Thanks a lot for the help. I read your previous post about M401/2, but just forgot to change it, thanks though!

Hmm,  mechanically sound printer ?   In other words do you feel it's nice and solid and should be producing the same results each time ?   For the grid what's the map look like,  is it random junk ?   Did you try changing the height of the BLTouch based on the docs that came with it ?   8m gap from bottom of BLtouch shell to bed.   

Jeff


Duet WiFi Powered FFCP with E3D legends hotend system.  BLTouch grid leveling.

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By ThePigSlayer 16 January 2017 04:51

Member · 10 comments

Yep my printer is pretty solid and prints consistently. I took it apart to make sure nothing got loose, tightened a few things, didn't help sadly. I am still getting deviations of 0.5mm maximum.

The grid is pretty random, I can upload the map if you want but I dont think it will help much.

I actually didnt get any docs with my BLTouch,, although it looked legit. I got it from spool3d.com. I modelled my own mount, and the distance from probe (retracted) to tip of nozzle is just 1.61mm. I read a distance of 2mm is optimal, so I don't think my mount height is causing any issues. Honestly at this point im thinking the probe is defective.

Thanks a lot for the help, I really appreciate it.

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By (In)Sanity 16 January 2017 04:55

Member · 267 comments

I thought the probe I got was defective at one point as well.  It turned out my config override was causing the issues.  You've ruled that out already.   See if you can get it to probe the same exact spot over and over to P0 P1, P2,  etc and see how much the values vary.

Jeff


Duet WiFi Powered FFCP with E3D legends hotend system.  BLTouch grid leveling.

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By dc42 16 January 2017 08:08

Administrator · 1,867 comments

If you are not getting consistent results from a Z probe, using a lower probing speed may help. It's the F parameter in the M558 command.


Duet WiFi hardware designer and firmware engineer
http://www.escher3d.com
https://miscsolutions.wordpress.com

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By ThePigSlayer 16 January 2017 09:14

Member · 10 comments

I probed the same spot 20 times and I ended up getting a standard deviation of 0.054.

Hopefully we can get this solved, I am losing hope though lol.

EDIT: Thanks for the input dc42. I dropped the probing speed to 100. I had already tried that with bad results, but this time I got a standard deviation of 0.026.
I will lower the speed again.

I dropped the speed again to 50. Standard deviation is 0.032.

Any other ideas?

Last edited by ThePigSlayer (16 January 2017 09:33)

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By T3P3Tony 16 January 2017 12:18

Administrator · 579 comments

If the BL touch is genuine then contact the manufacturer and ask what repeatability they expect. Could be a hardware fault.


Duet Wifi Hardware Designer
www.duet3d.com
www.think3dprint3d.com

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By (In)Sanity 16 January 2017 14:20

Member · 267 comments

I just ran a bed probe:

This was on a dirty piece of glass with some left over print residue.   
35 points probed, mean error -0.125, deviation 0.055

On a different piece of semi clean glass:
35 points probed, mean error -0.050, deviation 0.076

and again on the same peice:
35 points probed, mean error -0.170, deviation 0.073

What command did you run to get the multi point probe ?   I can try that.

Edit: Whatever my results I'm getting really nice flat first layers with even widths.   Probes were done at F300.

Jeff

Last edited by (In)Sanity (16 January 2017 14:44)


Duet WiFi Powered FFCP with E3D legends hotend system.  BLTouch grid leveling.

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By Syko_Symatic 17 January 2017 00:00

Member · 31 comments

So I will take the 5v and Gnd from the expansion port (pin 1 & 2) also taking the Servo pin from the same source (pin 8 (heater  3)).

Now when wiring the bltouch black and white wires into the DuetWifi Z- probe pins do they go to 3.3v and Gnd or Z- probe in and GND?

Also is it OK to crimp the resistor in with the pin connectors?

Last edited by Syko_Symatic (17 January 2017 00:01)

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By ThePigSlayer 17 January 2017 00:19

Member · 10 comments
Syko_Symatic wrote

So I will take the 5v and Gnd from the expansion port (pin 1 & 2) also taking the Servo pin from the same source (pin 8 (heater  3)).

Now when wiring the bltouch black and white wires into the DuetWifi Z- probe pins do they go to 3.3v and Gnd or Z- probe in and GND?

Also is it OK to crimp the resistor in with the pin connectors?

Z probe in and gnd. Be sure to use probe type 5 in M558. Also I dont see any problem crimping the resistor in the pin connector, as long as they are connected properly across. It might be easier to strip some insulation further up the wire though and put a bit of solder, but either or should work.


-----

And (In)Sanity here is my probing files, I have been using G30 S-1 to probe the single spot, the centre of my bed. For the G32 probe (auto bed compensation) my bed.g file contains this:

M98 Pdeployprobe.g
; Probe the bed at 5 points
G30 P0 X25 Y15 H0 Z-99999
G30 P1 X25 Y175 H0 Z-99999
G30 P2 X185 Y175 H0 Z-99999
G30 P3 X185 Y15 H0 Z-99999
G30 P4 X100 Y100 H0 Z-99999 S
M98 Pretractprobe.g

My mesh leveling macro is as follows:

G91
G1 Z6 F200
G90
M98 Pdeployprobe.g
G29 S2
M557 X20:180 Y20:180 S40
G29
M98 Pretractprobe.g

I have contacted Antclabs, but if anyone has any other suggestions please let me know! Thanks

Last edited by ThePigSlayer (17 January 2017 00:24)

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By Syko_Symatic 18 January 2017 22:45

Member · 31 comments

Do you have to define the servo pin anywhere? I'm thinking back to the way you use pins_Rumba.h to define the pins used in marlin, is there anything similar.

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By dc42 18 January 2017 22:52

Administrator · 1,867 comments

The servo pin is defined by the P3 parameter in the M280 commands in the deployprobe.g and retractprobe.g files.


Duet WiFi hardware designer and firmware engineer
http://www.escher3d.com
https://miscsolutions.wordpress.com

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By Syko_Symatic 18 January 2017 23:13

Member · 31 comments

Excellent! Do you define the bed limits for probing anywhere? Does this all currently look on track?

Config.g:
; *** BLTouch and Compensation
M558 P5 X0 Y0 Z1 H3 F200 T5000           ; BLTouch Z probe, used for homing Z axis, dive height 3mm, probe speed 200mm/min, travel speed 5000mm/min
G31 P1 X-25.0 Y58.0 Z-1.0               ; Set the Z-probe position and threshold

Bed.g:
G28 ;home all
G91 ;relative mode
G1 Z4 F200 ;move Z up 4mm for clearence
G90 ;absolute mode
M98 Pdeployprobe.g ;call macro
G29 S2 ;clear bed compensation
G29 ;run auto bed mesh level
M98 Pretractprobe.g ;call macro
G1 X10 Y10 F5000

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By Sniffle 19 January 2017 00:54

Member · 60 comments

this is from my own config

M557 X20:290 Y60:280 S60 ;probe boundaries with roughly 16 points (290-20=270/4=67.5 280-60=220/4=55)

bounding box of x20 to x290, y60 to y280 with 60mm spacing

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By zzing 19 January 2017 00:56

Member · 11 comments

Deckingman said "I currently use DC42s excellent probe" what is this probe? I am in the market for my next printer...

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By Sniffle 19 January 2017 01:15

Member · 60 comments
zzing wrote

Deckingman said "I currently use DC42s excellent probe" what is this probe? I am in the market for my next printer...

IR probe

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By dc42 19 January 2017 07:39

Administrator · 1,867 comments
Syko_Symatic wrote

Excellent! Do you define the bed limits for probing anywhere? Does this all currently look on track?

Config.g:
; *** BLTouch and Compensation
M558 P5 X0 Y0 Z1 H3 F200 T5000           ; BLTouch Z probe, used for homing Z axis, dive height 3mm, probe speed 200mm/min, travel speed 5000mm/min
G31 P1 X-25.0 Y58.0 Z-1.0               ; Set the Z-probe position and threshold

Bed.g:
G28 ;home all
G91 ;relative mode
G1 Z4 F200 ;move Z up 4mm for clearence
G90 ;absolute mode
M98 Pdeployprobe.g ;call macro
G29 S2 ;clear bed compensation
G29 ;run auto bed mesh level
M98 Pretractprobe.g ;call macro
G1 X10 Y10 F5000

The Z-1.0 in the G31 command is wrong because the trigger height will be positive. You need to define the probing grid somewhere using M557. You don't need the G29 S2 before the G29.


Duet WiFi hardware designer and firmware engineer
http://www.escher3d.com
https://miscsolutions.wordpress.com

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By Syko_Symatic 22 January 2017 16:22

Member · 31 comments

So I have wired everything loaded all my macros, re-pinned a z-stepper (grr) and now everything is nice and smooth. I am now stuck on how to calibrate the BLTouch on the Duet? I have done it in marlin before but wondered if anyone can point me in the right direction when doing it with the Duet?

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By ElmoC 23 January 2017 01:32

Member · 17 comments

I got my BLTouch installed and working on my CoreXY printer.  I can home Z with it with no problems.  I am now trying to get the rest of the configuration files setup for it.

I am running on a Duet 0.8.5 with 1.16 Firmware.  My BLTouch (when looking from the front of the printer) is to the right and back of the nozzle (X50 Y37).

In config.g, I have
M558 P4 X0 Y0 Z1 H5 F100 T2000        ; Switch for Z probe.
                    ; Move 5mm between probes.
                    ; Probe speed 100mm/min. 
                    ; Travel speed 500mm/min.

G31 X50 Y36 Z2.35 P5            ; Set the probe height and threshold (put your own values here)

From what I was reading for the G31 command, when I home Z and it triggers, it should set the Z position to 2.35.  This is the distance I measured the nozzle is from the bed after homing the Z axis.  But after homing, Z is at zero.  So I'm not understanding something here.

For the axis minimums (this command is before the M558 and G31 commands), I have...
M208 X-8 Y0 Z0 S1            ; set axis minimum (adjust to make X=0 and Y=0 the edges of the bed)

Another question I have is with the G30 probing and the XY locations.  If I use G30 with X150 Y100 in the bed.g file, where is the nozzle position suppose to end up?  Would the nozzle be at 150,100 or would the offsets in the G31 be applied and the nozzle would actually be at 100, 64?

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By Hey_Allen 23 January 2017 06:18

Member · 12 comments
Sniffle wrote

according to the bltouch people, to work with 3.3v logic electronics you only need a 240ohm resistor in line with the 2-wire endstop.  that could be where your not getting a response.

I am feeling a little slow here, but is this in series with one of the wires, or bridging the IN and GND wires at the PROBE connector on a DuetWifi?

I finally got the +5VDC, COM, and H3 connections correct, and the probe deploying/retracting, but am not getting any input from the probe, and am really starting to doubt my wiring of the sensor portion.

Currently I have a 240 Ohm resistor across the two wires, crimped into Dupont pins with the wires from the hall sensor output, but it shows up as 0 on the Z-Probe on the web control screen when tested with the auto-test macro that was posted in this thread, nor if pressed directly.  If it is unplugged, I see a value of 1000 on the Z-probe, and the field is shaded red.

Last edited by Hey_Allen (23 January 2017 06:39)