The printer nozzle starts at z=10mm

Hi
I am using kossel mini delta 3D printer. Usually I print after auto-leveling it then I make sure that the Z coordinate is correct by sending G1 X0 Y0 Z0.4 (its location just 0.4mm above the heated bed). However when I send the print command the hot end goes down and stops at a level of nearly 10mm then it starts printing or let me say it tries to print

Have you checked the gcode to see at what z value the print starts? This will tell you if the problem is with the printer or the slicer.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Hi
have a look please at this screenshot from Sli3r
[drive.google.com]

i forgot to mention that when i re-enter G1 X0 yY0 Z0.4 the level of the hot end (Z) equals the strating level of the printing process

I have this same problem, with my Z starting at 5mm below my nozzle.
I have a corexy printer, the bed moves down as it prints from top down.
I've adjusted my firmware z offset settings to 0.
I've cleared my eeprom out to factory defaults.
But I still can't print with this issue.
If anyone has some more ideas on this, it would be much appreciated!

After you home the Z Axis, send M114 and it'll tell you where it thinks the Z axis is.

For the OP, it kind of sounds like the travel after homing isn't set right.

Eg. Deltas are homed to Max, if you tell it that it's 270mm away from the bed when homed, when it really is 280mm, then there's the 10mm you're missing.

I had remembered my settings wrong.
After I rechecked after your suggestion, here's where I'm at.
G28 - moves the bed up to the induction probe. it lights up, then lowers down a bit.
At that point, it's 2mm away from my nozzle.
My lcd screen shows Z -3mm.
And M114 also shows Z -3.
if I then use pronterface, (Z -1) I'll be just touching my nozzle.
And then M114 will read z -5.

I don't know if this helps any, but after reading many many posts about this issue...
I tried using G92 Z0 after I was touching the nozzle.
But then once I did G28 again, it would go right back to what it was before, 2mm away from nozzle.

sounds like incorrect z offset stored in the eeprom

I thought it was the z offset in eeprom as well. i've reset the eeprom back to factory defaults.
And i've set the z offset setting in firmware to different numbers, including 0.
i've attached my config file.
i'm running marlin (smartcore-master) mk7.

Heres a video of my homing problem:
smartrapcore homing issue

If I tell pronterface to move the bed up (z -2mm), it will just touch the nozzle.
Then, I'll set z with G92 Z0.
And when I re-home with G28, everything gets reset back to what you see in the video.

And here's what my eeprom has stored.
SENDING:M501
echotored settings retrieved
echoteps per unit:
echo: M92 X80.00 Y80.00 Z80.00 E85.00
echo:Maximum feedrates (mm/s):
echo: M203 X250.00 Y250.00 Z70.00 E50.00
echo:Maximum Acceleration (mm/s2):
echo: M201 X6000 Y6000 Z2000 E10000
echo:Acceleration: S=acceleration, T=retract acceleration
echo: M204 S3000.00 T3000.00
echo:Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s)
echo: M205 S0.00 T0.00 B20000 X20.00 Z10.00 E5.00
echo:Home offset (mm):
echo: M206 X0.00 Y0.00 Z4.00
echoID settings:
echo: M301 P16.00 I0.90 D71.43
>>> G28
SENDING:G28
>>> G1 Z170
SENDING:G1 Z170
Disconnected.

echo: M206 X0.00 Y0.00 Z4.00


you have 4mm z offset

try setting this to Z1.00 see if thats any closer

That's what I thought too. I changed this to M206 Z0, but it didn't seem to make any difference.
This morning, I was able to dink around with some settings and I got my nozzle to touch the bed after homing with this in my start gcode:
G1 Z-1
G92 Z0
G1 Z-1
G92 Z0

I had to do this twice in Cura, otherwise it wouldn't work.
this ends up being too close to the bed after homing, but at least I'm getting somewhere with it.
I still don't quite understand why I can't just adjust it with my eeprom setting by changing M206 value.
Or maybe i've been working on this too long and am still not doing something right?

In your config.h

Quote

// Travel limits after homing
#define X_MAX_POS 170
#define X_MIN_POS 0
#define Y_MAX_POS 140
#define Y_MIN_POS 0
#define Z_MAX_POS 170
#define Z_MIN_POS -5

I tried setting Z min pos -5 in my firmware, totally screwed up Z offset when i did a G28
Try setting it back to zero

Thanks for trying that! I was thinking that i've tried that as well, but maybe it was with a different version of marlin/setup in all my troubleshooting attempts.
I'll give it a shot and see if it helps.
Thank you for your advice!