Delta z height AC Predator

Gary

Normal Homedelta below
Below obviously moves z height. It becomes 441.42

; homedelta.g
; called to home all towers on a delta printer
;
; generated by RepRapFirmware Configuration Tool v2 on Tue Feb 26 2019 21:31:01 GMT+0000 (Greenwich Mean Time)

G91 ; relative positioning

G1 S1 X490 Y490 Z490 F1800 ; move all towers to the high end stopping at the endstops(S1 checks for endstops) (first pass)

;below 3 comment/uncomment
G1 X-5 Y-5 Z-5 F1800 S2 ; go down a few mm GARYuncomment (S2 - Ignore endstops while moving. Also ignore if axis has not been homed.)
G1 S1 X10 Y10 Z10 F360 ; move all towers up once more (second pass) GARYuncomment
G1 Z-5 F6000 ; move down a few mm so that the nozzle can be centred GARYuncomment

G1 Z-10 F1800 ;need to move down for x0 y0 to complete

G90 ; absolute positioning

G1 X0 Y0 F1800 ;force to centre
;G92 Z456.747

jay_s_uk

One thing I have noticed is your endstop adjustments in M666 are a lot larger than mine

M666 X0.081 Y0.238 Z-0.319 A0.00 B0.00

What 'S' value are you using at the end of your bed file?

Gary

@jay_s_uk
I'm sure it's your bed file with S6

jay_s_uk

Try overriding the M665 and M666 values and then reprobe.
I.e. resend whats in config and then probe

Gary

@jay_s_uk
Yeah I did that before. I deleted config override and re-probed, but I've noticed that re-probing overwrites the M665 and M666 values in the override file. Worth another try though. When you said your endstop adjustments were smaller than mine by how much?

jay_s_uk

@Gary

The code I included is my endstop M666.

As you can see, my X is 0.081. Yours is -6.790

jay_s_uk

I don't know how yours can be so different unless the original owner messed with the little metal flags on the top of the carriages.

Gary

@jay_s_uk
The flags look/feel the same as my other stock machine. I'll need to get to the endstops as that's a huge difference.

Just done another re-probe and similar results.
M665 L440.000:440.000:440.000 R224.513 H456.388 B185.0 X-0.646 Y-0.364 Z0.000
M666 X-6.930 Y3.322 Z3.607 A0.00 B0.00

jay_s_uk

I would investigate your X endstop then as its 10mm different to your Y and Z enstops

Gary

@jay_s_uk
Yes. Got my finger under all of them and one is maybe a 0.5/1mm higher, not 10. Disassembly required. Never seen an endstop could it be upside down?

Gary

@jay_s_uk
I got the error " Warning: the height map was loaded when the current Z=0 datum was not determined probing. This may result in a height offset." Just wondered if the problem could be anything like the link below?

https://forum.duet3d.com/topic/10835/z-0-datum-was-not-determined-probing/3

I can kind of see that having both a Z endstop switch and a Z probe could cause a problem, as the z tower is not the z height.
Mine Firmware is: RepRapFirmware for Duet 2 WiFi/Ethernet 2.04 (2019-11-01b1)

Have you got the same firmware version?

jay_s_uk

@Gary

I wouldn't worry about the message around the height map just yet.

If you're going to stick with RRF2 for the moment, I would be upgrading to 2.05.1
I'm on the latest RRF3.01 release and I use conditional gcode in my bed file.

You need both a Z stop and a Z probe. The Z stop is set at the maximum end to signify its at the top of the tower. The firmware knows that the Z stop is for the Z tower and will treat it accordingly.

Gary

@jay_s_uk
Will update the firmware. It was just a thought as X-6.790 and my probe offset of 5.52 gives 1.27mm which would correlate roughly to what I felt with my finger maybe.

jay_s_uk

@Gary

What do you mean your probe offset is 5.52? In your config, your Z probe offset is 17.656

Gary

@jay_s_uk
Sorry I meant initial hot end paper touch before using probe. z=0 at this height.

Gary

Updated, checked all endstops/tabs and they all look okay. Similar distances and wiring the same. Just done another probe and config override as below.

M665 L440.000:440.000:440.000 R227.000 H456.747 B185.0 X0.000 Y0.000 Z0.000
M666 X0.000 Y0.000 Z0.000 A0.00 B0.00

That can't be right all zeros. I did notice that the first probe was not in the center of the bed - 10ish mm out.

Gary

Hi, Sorted at some point the X belt had twisted with the non-toothed side running on the stepper. I didn’t even notice when checking the stepper grub screws. I couldn’t see the belt twist as it’s slightly recessed on the machine, but I noticed when looking closely at the carriage and tabs. Really noticeable when you manually move the carriage up and down. It makes sense now as when I did a HomeDelta quite often, but not all the time, the interface would report not all axis homed and they weren’t. I just thought it was an annoying “feature” that would sometimes happen and I would have to click Home again. The board was turning the stepper the 490mm distance I have in my HomeDelta and not triggering the end stop giving the error. Also when doing probing from high up the results were inconsistent – belt slippage. Down low with slow probes it was okay. After a Home the X and Y values were not zero on the interface and when touching bed the hot end was not centred on the bed. Now to change the belts and somehow fix the bed which got smashed at the edge when the Perspex lid hit it!
M665 L440.000:440.000:440.000 R226.630 H455.788 B185.0 X0.093 Y0.750 Z0.000
M666 X-0.012 Y-0.045 Z0.057 A0.00 B0.00

dc42

@Gary said in Delta z height AC Predator:

@jay_s_uk
Yeah I did that before. I deleted config override and re-probed, but I've noticed that re-probing overwrites the M665 and M666 values in the override file. Worth another try though. When you said your endstop adjustments were smaller than mine by how much?

It will only do that if you have M500 in your bed.g file, or you send M500 manually. I do not advise using M500 in bed.g.