werid z starting printing much higher than anticipated...

otaku521

@t3p3tony
Yes when I go G1 Z0 it is a good paper feeler grip (like typical feel when I do paper feeler)
then start print i have to use -1.35mm baby step... this IMHO doesn't make sense...
if it was +/-0.2-0.3 maybe... but -1.35mm made me think there is something really wrong ... but I have no idea what

T3P3Tony

@otaku521 if you do a G28 and then G1 Z0, how far above the bed is the nozzle? Is it paper feeler close or~1.35mm above. If it is the latter then you need to adjust oyur config so that it is.

I think is sensible to have a home command in your start gcode.

otaku521

@t3p3tony
It is after g28 before print it is paper feeler close
But when start print and re home again it is higher than anticipated

Thus I have to do baby step that large (which results me to perminate to add it in my config file for now on

The bottom of the mini ir sensor there is enough gap that I can see the hex of the nozzle to the tip

Maybe g28 is running too fast on z to get an inaccurate reading?

Note that i am using a 2mm black PEI sheet like I mentioned above

otaku521

I have uploaded the video for your reference...

https://youtu.be/p8XtWKYzo_I

T3P3Tony

@otaku521 g28 should produce the same results no matter if it is run from the command line or from a gcode file. Can you test it multiple times from the command line to assure repeatability.

otaku521

I know... this is why it is weird....
so far I am wondering if my config and other scripts are fine ?

BPisLife

@otaku521 Sorry if you already mentioned this, but I was having an strange issue like this to and it turns out my slicer (simplify3D) was setting the Z to be .18 for the first layer. If my z=0 was tuned to approx. .1mm off the bed, then it would be .28mm off the bed and the print wouldn't adhere.

Just a thought, check out your gcode for the first layer and see what it sets Z to, then manually move the Z to the point it says after printing and you may see the gap. If so, then you need to either A adjust your slicer or your leveling. This is of course only assuming you are seeing what I am describing here.

otaku521

@bpislife you are 0.1-0.2xx off.. while I am 1.xx off... this made me think otherwise....
the only thing is I think is the 2mm PEI sheet on the bed not being correctly read by mini IR probe... so I am thinking of switching back to BL Touch and see

T3P3Tony

If the PEI sheet was not being recognised l would expect that to happen either way. I just had a thought though. Are you probing the bed in your prints but not when doing a normal test of G28?

SputnikOC3d

I have the same issues and have been plagued by it since day one. I cannot resolve ... I initially chalked it up to inconsistency of the BL Touch, but the more I deal with the issue it seems to be some arbitrary value created by the firmware.

I have to babystep in EVERY print - using a 5-6 perimeter skirt - and hope I can step it in in time before the actual part starts. Circles are particularly ominous to get right ... in time.

If I dont get adhesion - then I get Elephants Foot [ alot ] as I err on the side of sticking this mother down.

all this to say ... youre not alone.

otaku521

@t3p3tony
No... I only probe when everytime I start the machine doing my Macro above which calibrate my leadscrews (from 2... now 3 (just installed a Duex5) and then I do some prints from there on... but I don't start script all my prints to go calibration at the beginning since I got the Mini IR Probe (Switching out the BL touch)... (which was "PITA"...)

otaku521

@sputnikoc3d

Thanks! I think it is problem with PEI with IR...
I used to have BL Touch on AnyCubic's Ultrabase... it was inconsistent... then I switch Mini IR with Ultrabase and it was a joy!.... then now with a bigger bed (420x320)... I have to cut my own PEI sheet (2mm) and now it literally drives me nuts!! (but PEI when printed on fine... it is very nice to use!)

I am thinking of installing BL touch back... but I might be plagued by inconsistencies again.... OH THE JOY of 3D printing! XD

AlexLin

@otaku521 said in werid z starting printing much higher than anticipated...:

then I switch Mini IR with Ultrabase and it was a joy!

was it? No problems due to the hole-pattern? What color do you have under the Ultrabase?

otaku521

@alexlin I never removed the sticker on the bottom... I just put it on top of my old MK3 200x200x3mm Alum bed and clip in with 4 binder clips... never had a problem... I am in process of tearing my old i3 clone and making another corexy