You'll notice on the hotend there is a "nub" next to the actual place where the plastic is extruded out. How the DaVinci knows where the bed is located is by touching that "nub" to the glass hold down bracket. At that point it will sense a completed circuit and move the bed away and try the next point.

If the wire gets broken, it won't work. If the "nub" or the the brackets have gunk on them, it won't work. If the bed is so low that the printer gives up before it touches, it doesn't work.

On a side note, you can have the bed "way too high" and plastic gunk on it and it will eventually stop without damaging anything. The DaVinci will push the bed down compressing the springs and then reverse.

Since one does get a reading, the wires must be working.

the error says:

"calibration fail
+335, +ERR, +ERR
[OK} to return
"

If it's the +999 error, the common cause is a bit of plastic on the hotend or the metal bed holder tabs that prevents electrical contact from happening.

The other thing that will cause the 999 error is that you have the bed adjusting screws way too tight and the DaVinci gives up before it ever reaches metal bed holder tabs. In this case the error is correct because the bed is simply too far out of adjustment. To fix this error, you loosen all 3 of the bed adjuster tabs enough that you get a reading and start the routine again.

Stenci has an app on this forum to try and help you with how many turns the screws need once you get a reading. Might not be perfect, but it can't hurt.

i am trying to run calibration on da vinchi 1.0 (auto calibration) . I am receiving an error (ive posted the pic). Can you help please

Those are the settings I have in Cura. How the stock XYZware or Slic3r speed settings convert to mm, I don't know. I do know that Cura puts the same kind of numbers in in the gcode that it generates as other slicers do, but since I'm able to enter the speeds in mm directly I never bothered to look into how the number is converts.

nevermind. found it. yes it is.

How does 130=7800 ? Its a factor of 60, is it steps ?

You can also take a look at Voltivo's collection of the original files that are the demo prints off the SD card. On mine the top of the Demo one looks like this.

; filename = composition.3w
; machine = daVinciF10
; material = abs
; layer_height = 0.3
; total_layers = 173
; total_filament = 3169.23
; extruder = 1
G21 ; set units to millimeters
M107
;M104 S200 ; set temperature
;M109 S200 ; wait for temperature to be reached
G90 ; use absolute coordinates
G92 E0
M82 ; use absolute distances for extrusion
G1 F1800.000 E-1.00000
G92 E0
G1 Z0.350 F5400.000  <-- Also set at .35 on the Demo files.

I do think your speed setting from slic3r (7800) is too fast though. I'm not sure the DaVinci can move that fast even if it's just a travel command.

If you slice something with XYZware to gcode, here is the line that matters.  G1 Z0.350 F2700.000

That means that the first layer is printed with the hotend .35mm off the glass (or at least that's what the gap is supposed to be, which is why you need to calibrate until it is).

Thats the xyzware slicer gcode / How did you get that ? from sd card?

Looked over some Slicr3 gcodes and it has G1 Z0.200 F7800.000
Thanks

That means that the first layer is printed with the hotend .35mm off the glass (or at least that's what the gap is supposed to be, which is why you need to calibrate until it is).

What is the correct ht required for offset ?
btw -for ABS and davinci 1.0.