G0 Z0 change

roth · 3 Oct 2018, 15:49

Where is this 3 mm distance specified ?

My procedure for determining Z0 is:

home
M564 S0
G0 Z0
G92 Z0
G1 Z5
G30 S-1 Zoffset see
Enter in settings config.g

I couldn't find config-override.g on the memory card.
I didn't use M500 either. I did it like in the video.
Just read it and entered it in the config.g under G31 P25 X0 Y20 Z1.16.

adavidm · 3 Oct 2018, 15:50

@roth

Here is a good place to start:

https://duet3d.dozuki.com/Wiki/Calibrating_a_delta_printer#Section_Auto_calibration

It will take you step-by-step through learning to calibrate your machine. Between that and the Tevo-specific information in the video, you will be up-and-running in no time.

RepRapFirmware's use of "GCode everywhere", although daunting at first, is one of it's key features and makes for some amazing capabilities. @deckingman's recent thread showing off his CoreXYUV behemoth is testament to that!

roth · 3 Oct 2018, 15:51

What would a real start code look like where it doesn't miss the whole heating bed every time ?

With the original MKS board it only goes down once and measures the height in the middle.

adavidm · 3 Oct 2018, 15:53

@roth

From the docs:

M665: Set delta configuration
Parameters

Lnnn Diagonal rod length
Rnnn Delta radius
Bnnn Safe printing radius
Hnnn Nozzle height above the bed when homed after allowing for endstop corrections
Xnnn X tower position correction1
Ynnn Y tower position correction1
Znnn Z tower position correction1

The H parameter is the homed height of the nozzle tip above the bed. Reducing that by 3mm will make Z=0 3mm higher

adavidm · 3 Oct 2018, 15:54

@roth said in G0 Z0 change:

With the original MKS board it only goes down once and measures the height in the middle.

Those three lines I gave you earlier should achieve something similar.

Again, best to familiarise yourself with the documentation and take small steps.

adavidm · 3 Oct 2018, 16:00

@roth said in G0 Z0 change:

Where is this 3 mm distance specified ?

My procedure for determining Z0 is:

home
M564 S0
G0 Z0
G92 Z0
G1 Z5
G30 S-1 Zoffset see
Enter in settings config.g

I couldn't find config-override.g on the memory card.
I didn't use M500 either. I did it like in the video.
Just read it and entered it in the config.g under G31 P25 X0 Y20 Z1.16.

That sequence looks like a way of calibrating the Z offset between the probe and the nozzle tip. That won't help you to find z=0 in normal operation. You should only need to calibrate the Z offset in G31 once, unless you swap nozzles or probes.

roth · 3 Oct 2018, 16:02

Yes I have my problems with that because I don't understand everything because I have to translate it into German.
I can translate some English but it is difficult to understand complicated texts.

And I don't quite know how the firmware works. Why you always make +3 mm with g0 z0.
Because normally it should still be at the value where you have determined 0 via the correction in G31 P25 X0 Y20 Z1.16..
With the MKS board it is at least so.
But there it was like this when an overdrive file was created which was ignored in the config.

roth · 3 Oct 2018, 16:04

@adavidm Yes the Offset is Z1.16. But he just ignores the input in the config without this G32 line in the start code.

adavidm · 3 Oct 2018, 16:27

@roth
Ah. I did not realise you were translating into German! Entschuldige

If you look in your config.g, you should see the following line:

M665 R115 L397.19 B155 H520.

The H520 is the vertical print height of your printer, with the same bed as in the video. Try changing this to H517. This will make the printer think that the height is 3mm smaller than before. You will need to reboot for this to take effect.

Did you set up the beg.g and other files the same as in the video? If so then you do not need to have G28 or G29 S1 in your start code. The G32 command will run bed.g, which already contains a G28 (to Home) and a G29 (to make a new mesh for bed compensation).

For now, after changing the height, try powering on your printer then running G32 from the console. The following should happen:

The printer will home
The probe will deploy
The auto calibration will run, with 13 points tested
The probe will retract
The mesh compensation probe will run

At that point you should be ready to print. You probably need to change your start code to include a bed and nozzle heating command early on. It is best practice to calibrate with heaters at normal operating temperature.

roth · 3 Oct 2018, 16:29

Yes i make all like the video.
You don't have to apologize.
I would have to work hard to improve my Englsch. I'm gonna grab a bite to eat.

adavidm · 3 Oct 2018, 16:30

@roth

Ok, good. Try making the change and test as I have suggested. I have to leave now but will be back later today this evening if you are still having problems.