How Do I Calibrate My Titan Extruder and Test Print?

[AaronGreen]

I'm unable to test the bed heater control, as I can't home the printer.

I've checked all the connections since moving, and everything is in place, however when I home the printer just rams X with the grantry and Y with the bed. The sensors are in place as well, so I'm guessing something isn't correct in the config again?

;Config.g

; General preferences
M111 S0 ; Debugging off
G21 ; Work in millimetres
G90 ; Send absolute coordinates…
M83 ; ...but relative extruder moves
M555 P2 ; Set firmware compatibility to look like Marlin
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X340 Y250 Z280 S0 ; Set axis maxima

; Endstops
M574 X1 Y1 Z1 S0 ; Define active low and unused microswitches
M558 P5 X0 Y0 Z1 H10 F200 T6000 ; Set Z probe type to modulated, the axes for which it is used and the probe + travel speeds
G31 X-44 Y0 Z7.03 P50 ; Set Z probe trigger value, offset and trigger height

; Z-offset (Z0.9). Higher value LOWER nozzle height
; Lower value RAISE nozzle height

M557 X10:340 Y10:240 S68 ; Define mesh grid

M307 H3 A-1 C-1 D-1 ; disable heater 3, which makes it available for use to control the BLTouch

; Drives
M569 P0 S1 ; Drive 0 goes forwards - X
M569 P1 S0 ; Drive 1 goes backwards - Y
M569 P2 S0 ; Drive 2 goes backwards - Z
M569 P3 S1 ; Drive 3 goes forwards - Extruder

M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation 16
M92 X160 Y160 Z1600 E615 ; Set steps per mm 16

M566 X600 Y420 Z12 E120 ; Set maximum instantaneous speed changes (mm/min) - (JERK)

M203 X6000 Y6000 Z500 E400 ; Set maximum speeds (mm/min)

M201 X1000 Y1000 Z1000 E250 ; Set accelerations (mm/s^2)

M204 P1000 T1000 ; Set Max acceleration for P=printing moves and T=travel moves
M906 X1600 Y1600 Z900 E1000 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

[dc42]

I suggest you test the homing switches, see https://duet3d.dozuki.com/Wiki/Connecting_endstop_switches#Section_Test_endstop_switches.

[AaronGreen]

Geez this is complicated. I haven't changed anything, and they don't work. I don't know why I'm going over this again.

The end stop LEDs for X and Y are on, yet all the physical connections are good. I would think it's too much of a coincidence that both of them have failed at the same time, but I suppose there's a chance, and I'll have to order replacements which will take a while to arrive.

In the Machine Properties, it says X and Y are 'No' and Z is 'Yes' with:

; Endstops
M574 X1 Y1 Z1 S0 ; Define active low and unused microswitches

Even though X and Y are triggered, according to the LEDs on the board. Unless this means that faulty switches can't be triggered either way, and they're still showing up as not triggered, because they're 'un-trigger-able'. The Z is always triggered at the start, because it uses a BLTouch sensor, but doesn't show an LED light. The X and Y sensors both being faulty, for some reason, is the only explanation why this doesn't work.

[dc42]

Are you sure that your endstop switches are active low (S0 in M574)? If the endstop LEDs on the Duet go out when you trigger them, they are active high.

[AaronGreen]

OK, so I've turned the power off at the wall and found the Duet finally reset the end stops. I'm not sure why it didn't reset the state of the end stops when I restarted the Duet in web control.

The end stops are simple metal sensor switches that become active when the gantry and bed pass over them at close range - the same that I've used in earlier versions. I can see their lights come on when I pass the gantry and bed over them, but during a Home All the gantry and bed keep moving thereafter, and ram the physical boundaries of the printer.

M574 X1 Y1 Z1 S0 is the current setting, but changing it to S1, for test's sake, doesn't fix it. The Home All ignores the end stops.

[dc42]

It sounds like your endstops locked up until you powered them off. Are you sure you are supplying them with enough supply voltage to function correctly?

[AaronGreen]

I'm using the expansion bay set up with my end stops. From memory, it had something to do with the voltage. I had a look around the documentation to try and find the wiring guide for this set up but didn't see anything. I'm not sure if Duet is using this system anymore...

[AaronGreen]

I also just realised, the X and Y were homing without ramming the printing, before I had to add S2 to G1 commands...

Home All would zero X and Y without a problem, but not Z. When I added S2 to the G1 commands, it started ramming the printer, so it can't be the power, or the switches.

[AaronGreen]

Well, I accidentally hit the erase button trying to move the board, and now it's a paper weight at best. Love this thing.

I only have a Mac, and the current documentation says I need a Windows computer, so I that's the end of the road by the looks of it.

[Dougal1957]

@aarongreen you can use a mac to re-program the board you will need to download and install samba 1.8

[AaronGreen]

@dougal1957 said in How Do I Calibrate My Titan Extruder and Test Print?:

@aarongreen you can use a mac to re-program the board you will need to download and install samba 1.8

I managed to find Samba1.8.tar on the Samba archive, download it, and run it in Terminal, but I can't find any process on here on how to utilise it in Terminal. I've never done this before.

[dc42]

There is also a download of Bossa 1.8 available for Mac.

[AaronGreen]

I got a hold of Bossa 1.8 and reinstalled firmware 1.20 quite easily, and I'm back to printing already, thanks guys.

I wasn't able to fix the gradually sloping X axis issue I had with the printer last time, but I'll confront that if it's still shows up.

The only other issue I had during the test printer today was multiple Z height settings for the print, which I don't remember setting.

[AaronGreen]

I tried finding an existing thread for this but wasn't able to...

The printer is printing above the established Z height calibration.

I calibrated the BLTouch offset to G31 X-63 Y0 Z2.6 P50. At this setting, the nozzle sits half a paper's thickness off the bed at G1 Z0.

However, when I print anything it prints [visibly at a guess] at Z1, or 1mm off the bed. Babystepping in down, even up to 5.5mm, does nothing. It's printed successfully in the past, usually half a mill higher than Z0 for some reason, and I'm able to babystep it down just to get the print away, but this is out of control.

I've included the Cura start code I set up a while ago, but haven't really discussed it with anyone here. I'm not sure if it's part of the issue. I thought maybe it has something to do with the executing, seeing that the Duet calibration tests are good, and the print data maybe wrong...

Config.g

; General preferences
M111 S0 ; Debugging off
G21 ; Work in millimetres
G90 ; Send absolute coordinates...
M82 ; Using Cura
M555 P2 ; Set firmware compatibility to look like Marlin
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X340 Y250 Z280 S0 ; Set axis maxima
M552 S1 ; Start WiFi Module

; Endstops
M574 X1 Y1 Z1 S0 ; Define active low and unused microswitches
M558 P5 X0 Y0 Z1 H10 F200 T6000 ; Set Z probe type to modulated, the axes for which it is used and the probe + travel speeds
G31 X-63 Y0 Z2.6 P50 ; Set Z probe trigger value, offset and trigger height

Cura Custom Start Code:

;FLAVOR:RepRap
;TIME:9941
;Filament used: 4.49025m
;Layer height: 0.1
;Generated with Cura_SteamEngine 3.0.4
T0
M190 S60
M104 S210
M109 S210
M82 ; absolute extrusion mode
Start Code
M280 P0 S160
M420 Z2 ; set fade leveling at 2mm for BLTouch (OK to send for Non BLTouch)
G28 ; home all
G29 ; bed probe
M82 ; relative extrusion
G92 E0 ;zero the extruded length
G1 X0.0 Y50.0 Z10.0 F3600 ; perform wipe and prime
G1 Z0.0 F1000
G1 Z0.0 Y70.0 E9.0 F1000.0 ; prime
G1 Y100.0 E12.5 F1000.0 ; prime
G92 E0 ; zero extruder again
;end start code
M82 ; relative extrusion mode
;LAYER_COUNT:398
;LAYER:0
M107
M204 T2500
M566 X1800 Y1800
G0 F3600 X176.318 Y114.382 Z0.3
M204 P1500
M566 X1200 Y1200
;TYPE:SKIRT
G1 F1500 X176.664 Y113.853 E0.03154
... and so on...

[dc42]

Your start GCode is running G28 to home the printer followed by G29 to generate and apply the height map. If you run those two commands manually, does G1 Z0 send the nozzle to half a paper's thickness, at any XY position?

Are you doing Z homing using the BLTouch or with an endstop switch?

[AaronGreen]

@dc42 said in How Do I Calibrate My Titan Extruder and Test Print?:

Your start GCode is running G28 to home the printer followed by G29 to generate and apply the height map. If you run those two commands manually, does G1 Z0 send the nozzle to half a paper's thickness, at any XY position?

Are you doing Z homing using the BLTouch or with an endstop switch?

Z homing includes the BLTouch.

A manual G28 gives me a half-paper thickness G1 Z0. However, doing a G29 THEN G1 Z0 at various places shows G1 Z0 at +1mm.

I had a look at the G29 readout and this is what I get:

However again, the bed is physically flat, as in I have placed the nozzle a half-paper thickness in 6 positions (4 corners and 2 internal) and physically measured the level of the bed. The readout I get is FAR from the physical level of the bed. Any ideas why it's very different?

BTW, I've seen this before (and didn't have a solution at the time), but if I levelled the bed according to the G29 readout until it was perfectly green the bed physically measured as obscure as this readout is.

I should also add that it's no longer doing a 12-point G29. It's doing a 9-point check, because according to the web control some of the far probe points are outside the bounds of the bed. I haven't set up the probe points using duet before, but I have the instruction thread on hand. I'd think that'd be something to fix next, but not the major contributor to the Z0 discrepancy.

Thanks David.

[dc42]

It looks like the bltouch trigger height depends on the XY location. This is something you can check, by measuring the trigger height at various XY positions.

One possible cause of this is that the print head doesn't stay level. A tilting print head will change the relative heights of the nozzle and the Z probe.

[AaronGreen]

@dc42 said in How Do I Calibrate My Titan Extruder and Test Print?:

It looks like the bltouch trigger height depends on the XY location. This is something you can check, by measuring the trigger height at various XY positions.

One possible cause of this is that the print head doesn't stay level. A tilting print head will change the relative heights of the nozzle and the Z probe.

I'll check the trigger height around the bed, the same as I did with the nozzle height, but it should be consistent, considering both are statically fixed to the gantry.

I'll also double-check the height of each end of the X axis profile, but I've also done this several times in the past with beer cans, and once again, the nozzle moves across the bed consistent 1mm above Z0. When it comes to print, it always adds height. Could the G29 throw the Z0 out as a result of it's mandate to establish bed height, whereas a G28 just establishes a true Z0 in the place it homes to?

[dc42]

@aarongreen said in How Do I Calibrate My Titan Extruder and Test Print?:

Could the G29 throw the Z0 out as a result of it's mandate to establish bed height, whereas a G28 just establishes a true Z0 in the place it homes to?

If the problem was a general Z offset, then possibly. But that's not the problem that your height map indicates.

[AaronGreen]

I've rebuilt the bed, and checked the squaring of the frame, and everything is tight.

The only discrepancy is the tensioning wheels on the bed chassis are tight enough to keep it steady, but increase the height of the chassis on the left side by half a mill. It's also opposite to the bed calibration results.

All I'm going to do next is calibrate the bed to the results screen, which I've laboriously done before, instead of a physical level.

I tried doing that tonight, but the Duet won't start the WiFi module for some reason, I have no idea why. It won't even do it using Pronterface. So I'm going to come back to it tomorrow.