Unable to home z axis

Kayjay

These are the results for the M98

11:12:17 AMM98 P"config.g"
HTTP is enabled on port 80
FTP is disabled
TELNET is disabled

droftarts

@Kayjay I’d say have a go with the Z movement tests, once you have your config.g sorted.

You can tell from the M122 response if the Z axis has stalled. Try moving Z, and if it doesn’t, send M122 and look at this line in the response:

Driver 2: standstill, SG min/max not available

The bit after SG min/max will have numbers. If the max is 1023, the axis has tried to move, but stalled. It could be that the Z axis is binding, particularly as you have two motors on Z.

Ian

Kayjay

I sorted the config.g, the PT100 wasn't configured to use the daughterboard, just a slip of the mind .

This is the result of all the drivers from M122. I tried to move z then did the M122

Driver 0: standstill, SG min/max 0/234
Driver 1: standstill, SG min/max 0/295
Driver 2: standstill, SG min/max not available
Driver 3: standstill, SG min/max not available
Driver 4: standstill, SG min/max not available

I assume this indicates that Z isn't trying to move. I can't get it to move using any Go or G1 command but it will move in homeall and homez.

I have made a video of Homeall.z which shows x and y homing, then x moving to 150 and y to 100 which is the centre of the bed. After that nothing happens, as though G30 is being ignored completely.

I'm busy trying to upload the video to youtube but at the moment I'm not able to, I do have an account but I have never uploaded anything to my account so it's a matter of another learning curve.

I am getting very close to giving in as nothing seems to works. I'd even send it to Josh at E3D but they no longer handle the Bigbox so I don't think they'll do a repair.To be honest I'd be happy to pay anyone who can make this darned thing work otherwise its the Anet A8 Plus. I am getting very frustrated even with the great help you've all given me. I feel there is an electronic problem rather than software. I'm just at a loss, you guys have been so amazing and helpful, your hints and tips have been amazing too but I just don't know what to do any more. For one I'm a novice so to speak, I don't understand half of the speak, I'd just be happy with a working printer that I can throw a sliced prog in and let it print me a nice result.

Phaedrux

It sounds like the Z axis isn't stalling, so that's a good sign.\

The reason it won't move the Z axis with G0 or G1 is probably because it hasn't been homed yet, So unless you've sent a G92 Z10 to force the Z axis into a homed position, it won't move.

@Phaedrux said in Unable to home z axis:

https://wiki.e3d-online.com/BigBox_Version_Overview

I think this may be an issue of Z axis steps per mm being incorrect.

The marlin config for the Bigbox pro hydrid is 1600 steps per mm on Z. You've got it configured as 400.

#define DEFAULT_AXIS_STEPS_PER_UNIT {160,180,1600,417.5} // default steps per unit for Titan BigBox

So try changing your M92 Z400 to M92 Z1600 and try to homeall again.

droftarts

@Kayjay Have you been able to post the video? Also, I’ve sent you a private message. Click the speech balloon icon at the top of the page to see messages.

Ian

Kayjay

@Phaedrux
Well, there is a small improvement, the bed now rises in the steps I have set in homeall, I have to keep homing but by hte time it reaches the top it crashes or rather would if I don't do an emergency stop. I've also tried holding my finger under the probe whilst it is homing , the LED lights but it doesn't stop, neither does it stop as it lights just before I hit emergency stop.

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.1.4 on Sat Aug 15 2020 09:44:17 GMT+0100 (British Summer Time)
G91                     ; relative positioning
G1 H2 Z-25 F6000          ; lift Z relative to current position
G1 H1 X-305 Y-205 F1800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000       ; go back a few mm
G1 H1 X-305 Y-205 F360  ; move slowly to X and Y axis endstops once more (second pass)
G90                     ; absolute positioning
G1 X150 Y100 F6000       ; go to first bed probe point and home Z
G30                     ; home Z by probing the bed

; Uncomment the following lines to lift Z after probing
;G91                    ; relative positioning
;G1 Z5 F100             ; lift Z relative to current position
;G90                          ; absolute positioning

The Z-25 setting is temporary to enable a quicker bed rise so I don't have to hit homeall a hundred and umpteen times. Obviously I stop it crashing before it reaches it's limit

droftarts

@Kayjay does the probe still give sensible numbers in DWC, ie 0 when not triggered, 500+ when triggered?

Can you post some pictures of the Duet and wiring?

Ian

Kayjay

@droftarts Yes, the probe numbers are still correct, 0 and 537. I've also managed to upload the video I made yesterday, I suppose it's out of date now as it shows that the bed doesn't rise after homeall but I thought I'd post it for completion. Here's the link, you may have to wait until 4pm for it to show, it's the earliest it would allow me to show it.

https://youtu.be/Xtr5PvMXFso

I'll also take some stills of the Duet wiring. Is it possible to post pics on here or should I put them somewhere else?

Kayjay

Kayjay

@Kayjay said in Unable to home z axis:

Kayjay

Kayjay

Kayjay

@droftarts
Are the pictures above ok or would you like some more specific areas, particular clear shots of wires and plugs, not a prob if you require them.

Keith

Phaedrux

@Kayjay said in Unable to home z axis:

Well, there is a small improvement, the bed now rises in the steps I have set in homeall, I have to keep homing but by hte time it reaches the top it crashes or rather would if I don't do an emergency stop.

Do you mean that G30 seems to be working now, or is it the G1 H2 Z-25 that is moving it up? That command will move it until it crashes, the probe won't stop it.

Can you get a better photo of the probe wiring and the ir probe itself?

Kayjay

@Phaedrux It's a bit of a mixture, if I comment out G30 the bed will rise whenever Homeall is activated, the head centres to the middle of the bed and the bed will rise the amount I have set in Homeall but if G30 is active ie not commented out then things return to as they were, all stops at the point G30 should home. I have also included two stills of the probe plug on the Duet and the plug on the probe itself.

Phaedrux

What happens if you move the print head to the center and then issue G30 in the console?

Also, can you send G31 and report the result?

Kayjay

Just an intersting item I found in my bits and bobs box. I bought it years ago, it was poorly printed as you can see but the circuit design and construction was good. It's a filament diameter sensor to detect variances in filament thickness and as such the flow through the hotend could be adjusted. I know Marlin was adjusted to enable this to be used and I used it on my old Prusa Mendel to good use but it meant me changing from Repetier (which was far superior at the time and may still be) to Marlin. If anyone wants to make one it can be found on Thingverse.

http://www.thingiverse.com/thing:454584

Keith

Phaedrux

While we still don't know what is wrong with your probe, I had an idea to try switching to manual probing so that you can maybe at least get up and running.

In config.g change your M558 P1 to P0 for manual probing. That will mean that when it gets to the G30 part in your homeall, it should pop up a dialog box asking you to jog the Z axis to touch the nozzle. Let's see if that works.

dc42

In your config.g file you have this:

M558 P1 H5 F120 T6000                   ; set Z probe type to unmodulated and the dive height + speeds
G31 P500 X0 Y25 Z2.5                    ; set Z probe trigger value, offset and trigger height

That looks correct to me, however we can't rule out the possibility that there is a non-printing character in one of those lines that is messing things up. So please send the following commands from the console, with no extra parameters:

M558
G31 T1

and check that they report the expected values.

droftarts

@dc42 said in Unable to home z axis:

So please send the following commands from the console, with no extra parameters:
M558
G31 T1
and check that they report the expected values.

Did this today with Keith, response was correct. One odd thing was probe reading was 0 to 1000, rather than 0 to 530. I suspect a damaged probe.

Ian