I note the Eddy NG method does the tap with the nozzle at 150 °C. The seem to think that a clean nozzle it worth not including the nozzle length change between 150 and printing temperature.
I’ve got 50mm/s first layer speed, and 100mm/s first layer infill. Now that I think of it, the former is used only for the first layer walls, so it’s not what I intended (I wanted 50mm/s max), so I will halve these values 
I keep acceleration for the 1st layer to 1000mm/s2 only, travel speed 80%.
Last but not least, things improved by raising Z offset a little bit (I was being too aggressive), and by new, proper input shaping. Weird enough, also, I just noticed I had pressure advance disabled on this filament definition file!
Here’s my new first layer:
There are so many variables that it is always easy to miss something, especially if you swap filaments frequently!
But, well, if you enter the mindset that you need to be the technician of your printer, the Sovol Zero is truly a little gem. I’m very happy I made this choice (coming from a CEL Robox, pure useless frustration).
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I just remembered that I swapped to a new after market PEI build plate and failed to do an Eddy calibration. Derp.
I was printing PETG yesterday and everything went well, then suddenly the first layer wasn’t adhering even though I didn’t change anything. There seems to be some mysterious magic going on behind the scenes. I lowered the Z offset, and that didn’t seem to help, as if it wasn’t doing anything. Lowering the Z offset at the start of printing, after the bed mesh and Z offset probe seemed to work but the entire process is so random that it’s difficult to know what works and what is luck. I tried saving the Z offset and rebooting but that didn’t seem to work. Of course, it reports 0.00 so I don’t know what secret offsets it’s saving behind the scenes. The Z offset on the Zero is confusing and too opaque to the user.
Fabio setting a Z offset adjustment in the OrcaSlicer start G code is both clever and a sadly desperate workaround to a problem that shouldn’t exist.
I just did the Eddy calibration with the after market PEI coated steel build plate. I printed the problematic PETG part from last night, but with a 0.00 Z offset in Mainsail. Nope. It printed several layers and the part stuck to the nozzle and started to make a blob-o-death.
I prefer a simple and transparent user interface so I know what’s happening. Barring that, I’d accept not knowing exactly what’s happening if I could tweak it to work and then not mess with it. The Zero is neither. I can tweak it to work, and at some random point in the future it’ll revert back to not working again.
The Zero first layers are unquestionably better than the SV08 where no amount of tweaking would produce a nice sheet of plastic for a first layer test, but it’s frustrating knowing that the Zero hardware is eminently capable of a perfect first layer and some mystery software is randomly preventing that.
Conclusion: When the Zero suddenly starts failing on the first layer, I’ll do an Eddy calibration, tweak with the Z 0ffset (maybe using Fabio’s start G code workaround), and I’ll hope for a Zero firmware upgrade to make a deterministic and persistent Z offset.
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If the Zero’s wandering Z offset continues to plague me, I’ll eventually become frustrated to do some experiments with Z offsets and a paper shim under the nozzle to try to reverse engineer what the Zero is doing behind the scenes. I’m almost to that frustration point. 
At the very least, it should help me to verify what Z offset in Mainsail equates to an actual Z=0 nozzle height so I can try to determine when the internal Z offset is changing.
The randomness is not random at all.
If there is plastic on the nozzle tip the Z0 result will be wrong. Trying to chase that by changing the Z offset gets 1 print done but sets up for failure on the next.
The only “work around” I can figure out is watch it like a hawk. Any filament ooze… abort and restart.
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As we know, the printer automatically does eddy current sensor bed leveling before every print.
Setting Z offset manually (either in Mainsail or through the printer display) should be done immediately after this phase, else the value will be over-set (to 0) by the automatic bed leveling procedure.
What firmware version are you using?
Applies to all with or without pressure sensor.
All methods use the nozzle tip as a micrometer anvil (and a spot on the bed). If it is not clean an accurate measurement cannot result.
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Probably the easier to understand (or longer) way of explaining the issue would go something like this:
During print start calibration, the printer tries to figure out at what height the nozzle is currently in relation to the bed as it doesn’t have this information from the previous print or any other sensor. For X and Y, that’s done with the end stop switches that are at the end of the rails and those can be heard clicking during the X and Y calibration process. However, there’s no end stop switch for Z. Instead, the end stop method is to probe the bed physically with the nozzle. Once it touches, that’s the zero and that defines the Z height that can be seen as “Result is z=” prints in the console. With a clean nozzle, this method produces good results. With a randomly dirty nozzle, the results are equally random. Because the Z offset is applied on top of this value instead of replacing it, the offset can’t be used to fix a bad result from the probe. It’s also not possible to automatically evaluate if that value was bad since there’s no other probing method available which could be used as comparison due to both pressure and eddy sensors relying on that same part, the nozzle.
I’m not sure if there’s any workaround solution existing for this to just manually set the Z height as there would still need to be some kind of Z end stop existing for the printer to know where the Z initially is. Probing with the pressure sensor using some other rigid part of the toolhead assembly could be a better approach but this hasn’t been planned for and there may not be any rigid enough part of the toolhead can make contact with the bed for making this work.
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I’ve been running the ZERO for about a month (pretty much non-stop) with different nozzles and materials and have not seen this issue affect a print. The nozzle is usually warm when it pressure probes the bed, so even if there were some filament on the end it would squash to produce a negligable difference ( I assume so small that it would not make a difference). I have never had to change z-offset. I have however had to increase most of the temp values in the standard profiles to ensure good bed adhesion. Would be interested to know how many others are seeing the same issues as yourself.