POLL - What is YOUR - Z axis offset for Prusa Mini?  

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

it all depends on the sensor (PINDA or SPINDA) and the print surface and how you calibrated the sensor

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

@oxygen

OK, So i've gone back to the User Manual and calibrating the sensor wasn't one of the steps listed. Working from Section 6 (page 14) 'Your first print'. 

Is there something i've missed here?? 

Please advise how critical it is for this to be done on a new Prusa Mini+? And if there's a reference directing this. 

I found this in the help section : 

https://help.prusa3d.com/en/guide/how-to-adjust-the-height-of-the-m-i-n-d-a-sensor-mini_154547

If it's something that will improve the quality / printability of the printer. Then I'll work through this too. 

Thanks. 

PS. 'Bondtech Heatbreak' in your signature, was this an upgrade or a requirement. (Ie. was the printer working well prior to this install). Thanks. 

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

-0.505 to -1.470

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

With calibrating the sensor I mean adjusting the height (visible in step 3 of the guide you pointing to) only I had issues with 0.8mm (the size of a credit card) my liveZ was -1850 and with a textured sheet you have to lower the Z by approx 200. LiveZ has a maximum value of -2000. I calibrated the SPINDA with 1.5mm and my Z varies now between -415 and -615. My choice to replace the heatbreak was done before I had the SPINDA sensor. In that period of time I had issues with under-extrusion (it could be that the issues were tied to the PINDA and if I would replace the heatbreak back my issues would still be solved...) same with the couplers and the boden tube -- my printer prints fine now.

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

-0.995.

After adjusting the position of the heatbreak (it was too low, extending too far out of the heatsink as delivered from the factory) and the SPINDA to match.

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

-1615 on the smooth sheet, -1920 on the textured.

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

-1.965  on the smooth sheet w/ PLA

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

After taking my hot end apart, mine's now recalibrated to -1.310 on the smooth sheet.

I can’t help thinking that numbers much higher than -1.500 suggest that either the SPINDA needs moving up a little, or more significantly that the heatbreak might need moving too,  With a poorly positioned heatbreak implicated in partial clogs and underextrusions.

POLL - What is YOUR - Z axis offset for Prusa Mini?

-2.000 and first layer is perfect. But, looking at the replies from others I may need to raise the heatbreak or SPINDA, which I probably wont do unless I start to have issues.

As mentioned in previous posts (and elsewhere), there's no "right" Z-offset value, because it entirely depends on SuperPINDA position. That is, depending on SuperPINDA height, one can get good results (first layer) with -0.2 Z-offset, while someone else is happy printing at -1,900.
If you're happy with your first layer, just keep as it is. However, it's good to know, that -2.000 is max negative value and so you won't be able to decrease it anymore if needed.

offset

Mine is now -1.450

If you put a space in the title, you don’t have to type a title

Mine is -0.908 for PLA/smooth sheet, and -1.3 for PETG/textured sheet.

After following the manual on how to set the initial height of the SPINDA, and performing 1st layer calibrations on the smooth PEI sheet with the included Prusament PLA samples I arrived at -1.315

When moved onto a 1kg spool of Prusament PLA, which was purchased along with the printer, I had to dial it back to 1.200

Take a zip tie from the package and place it under the SuperPINDA sensor. Use the middle part of the zip tie, not the tip.

Was previously -2.00 for smooth sheet. Switched to textured sheet for PTEG and -2.00 was too high. Had to move SuperPINDA up some. Now sits at -.350 for smooth and -.750 for textured.

I have two separate Mini+s. 

First Mini - 1.675 on smooth sheet, used zip tie measurement. 

Second Mini - somewhere .800 - 1.000 on smooth sheet, used 1.5mm measurement.

I haven't calibrate texture sheet on both printer, yet. Planned to do it shortly.

move the PINDA ...

FWIW, after moving the SuperPINDA several times (as well as disassembling the hot end - including swapping nozzles and the heatbreak, after each of which it is necessary to recalibrate) my Mini+ is now holding at -0.770 on the smooth sheet and -1.200 on the satin sheet (although I haven't recalibrated to use the satin sheet since my last changes, so that might not be accurate).

If you are getting values higher than -1.200 on the smooth sheet I'd definitely recommend resetting the height of the PINDA (I use a credit card between it and the steel sheet).  

Advice

That is sound advice.  

Posted by: @richard-d

FWIW, after moving the SuperPINDA several times (as well as disassembling the hot end - including swapping nozzles and the heatbreak, after each of which it is necessary to recalibrate) my Mini+ is now holding at -0.770 on the smooth sheet and -1.200 on the satin sheet (although I haven't recalibrated to use the satin sheet since my last changes, so that might not be accurate).

If you are getting values higher than -1.200 on the smooth sheet I'd definitely recommend resetting the height of the PINDA (I use a credit card between it and the steel sheet).  

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

I know I'm late but this worked spot on for me...

RE: POLL - What is YOUR - Z axis offset for Prusa Mini?

My setting is -1,780 mm and I think is too high value on smooth PEI sheet. I sometimes have problem with first layer but sometimes it's perfect.
Must I raise sensor or lower it ? For me I must lower it 😎 
It's correct way of lowering Live Z adjust ??