No Z_PROBE_GAP in firmware

WhiteRenard

Hey,

I've been trying to get Z probe and auto bed leveling to work on my Smartrapcore (coreXY). In the Z-Probe guide it mentions a Z_PROBE_GAP variable which I don't seem to have in my configuration. I'm running 0.92.9.
My probe is a 4mm inductive sensor btw, but I think the guide was written with a mechanical probe in mind, specially the photo is a bit confusing since it shows the probe is below the nozzle. I'm not even sure what the definition of Z_PROBE_GAP is exactly.

I downloaded the dev version as well, but the variable wasnt there either.

P.S. Oh and also can all the required variables to calibarate Z-probe be changed from EEPROM in repetier host (including Z_PROBE_GAP)? I've already done all the activating and endstop configurations.

Repetier

I think the guide was for a different firmware. I think what comes close to this is Z_PROBE_HEIGHT in our firmware.

WhiteRenard

Repetier said:

I think the guide was for a different firmware. I think what comes close to this is Z_PROBE_HEIGHT in our firmware.

But there's also a Z_PROBE_HEIGHT in the guide. So the Gap variable was removed?
Is there a more up to date guide available?

Repetier

Ok found what you mean. In the complete guide we say Z_PROBE_BED_DISTANCE but at one place it was not renamed. Normally no problem as you use the configuration file you get and there the right names are already included. I highly advice to use the online config tool for configuring firmware. Makes updating much easier.

WhiteRenard

Repetier said:

Ok found what you mean. In the complete guide we say Z_PROBE_BED_DISTANCE but at one place it was not renamed. Normally no problem as you use the configuration file you get and there the right names are already included. I highly advice to use the online config tool for configuring firmware. Makes updating much easier.

Alright, I configured my firmware again with the online tool. To find out the Z_PROBE_HEIGHT value, I moved the extruder to the highest point on the bed. Homed Z to Max then brought the bed up (Corexy) until it was just touching the nozzle. (2mm Z Height) Then increased the distance until probe deactivated, at 4.2mm.
I thought the variable should be difference between these numbers, but nozzle didn't even reach the bed at 2.2.

So I kept increasing the value until I found 6.1mm (Pretty much the sum of Z height and probe deactivation height) was somewhat correct.
However, the ABL doesn't compensate enough and one side of the print is completely squished while the other side is round and barely sticking to bed.

This is my Start Gcode script:
G28 ; Home G1 X5 Y35 ; Getting Ready for first probe G32 ; ABL
I move to X5 Y35 on second line, because that's where I've attached the first aluminum tape on my glass bed.
My Z axis movement speed is 15mm/s.
And I do see the Z axis moving to level the bed but apparently it's not enough.

WhiteRenard

I'd appreciate if you could help me out a little here, Repetier.
Thanks ;)

Repetier

So you are using aluminium tape for the induction sensor to work?

1. There should be no need to autolevel every time. Except if your bed changes position on it's own. Normally just home and print is enough. G32 S2 stores autoleveling in eeprom so it is still active after restart.

2. G1 X5 Y35 can probably be omited as g32 has it's own measurement points

3. Not sure how good aluminium tape works esecially if it gives always same height.

4. What method do you use for measuring tilt? 3 points require 3 precise points as they give rotation for whole bed. Points should have maximum distance and not be on a line. If points are not so precise it is better to use a nxn grid instead giving you an average tape.

5. Repetier-Host has a height map function to measure your heights after autoleveling. Use it to test what sensors report. If sensors report plain plate and print not there might be a measurement problem. You might also see other things like plate not being planar (if tape is sticking to glass). In any case does it give more insight into the problem.