Good advice or incorrect instructions?

[Lord-Memester]

(Might not be verbatim, but you get the idea.)

In the Z-offset adjustment menu, one of the menu items notes that "For [the] best results, have [the] nozzle touch [the] bed".

I understand this from the point of view of a machine that needs to know the actual zero. However, it is widely suggested to perform the procedure with a piece of paper.

Is there any special significance to this advice?

I ask because I've recently been suffering from bed adhesion issues, and I've used the same Z-offset for a long time with no issues prior. I suppose it's entirely possible the issue may be something else, but that's beside the point here. I'm mostly curious why the advice given seems to contradict the advice provided by the vast majority of printer users.

(@classicrocker883 and @mriscoc)

[Lord-Memester]

Well, it currently seems like good advice. The bed adhesion is working great now that I followed the advice, but I still can't help but wonder why this works when the vast majority of advice says otherwise.

[classicrocker883]

you're right on it being good advice. the goal is so the printer knows Exactly where the bed is. you can test this by moving it to Z 0.00. if the nozzle isnt touching the bed, its too high and if you want to you can put your hand right on the fan shroud and feel for the fan vibrations to stop, once that happens the vibrations move through to the bed and that's when you know the nozzle is touching, of course you can visually see this. once you get the correct Z offset, you can now move onto the 4 bed corners with their knobs. instead of moving the nozzle up and down in the center of the bed, when it moves to each corner turn each knob accordingly as the nozzle is above each set screw. after you do this, its good to check the Z offset once again in the middle of the bed. then you can go around to each corner one more time to be sure.

you want the printer to know where the bed is when Z is 0 because when it starts to print like 0.20mm or whatever for the first line, the nozzle is exactly that far away. once you add paper or a feeler gauge to the mix - you're just adding another variable to deal with.

I haven't use the paper trick so long I barely ever have to relevel the bed after so much time and many prints lster

I got myself a Voxelab Aries, it was a good deal 2nd hand with barely any hours. It definitely isn't as upgradable as like the Aquila or Ender 3, but still a not bad printer. One of the things it has is wifi so you can print right from the voxelmaker slicer.

Anyway.... the procedure for leveling the bed is like this: so when you press the button to level, the Bed rises up (square frame similar to a Core XY) and asks you to adjust the Z offset. it actually says on the LCD to have the nozzle touch the bed. because it's moving in only the up and down direction, there is no chance at scratching the bed, just be sure not to go down further with the nozzle. then it moves to the 2nd point which is above one of the bed knobs, you adjust them so the nozzle is just touching the bed and it goes to the next and last point for you to do the same thing.

after very good results, I decided to copy the procedure to my Aquila, with 4 knobs to level the bed. first thing is to get the correct Z-offset. if you add paper or a gauge in between, you're literally adding another variable when it comes to bed leveling/tramming. the point of omitting that and going straight to the bed with the nozzle gives you a True Z-offset.

side note: there are 3 points of contact, and originally there are only two front knobs you can adjust, because the 3rd in the center is fixed, I turned the 3rd fixed point to be like the other 2 with bedsprings so they're all the same and adjustable. besides all that, the way you're "suppose" level/tram is how its done on the Aries. otherwise adding something in between just complicates things and you end up chasing your tail.

[Lord-Memester]

It's just odd that so many recommend the use of a piece of paper to level the bed, even though it would be simpler and more accurate to do it how it's done (how it's done meaning with direct nozzle-bed contact) on the Aries and--with this firmware--on the Aquila.

[classicrocker883]

well the way it's done with paper adds an extra step along with that variable, for some it's easy to judge where the nozzle is vs when it's directly contacting the bed. it's extra assurance so the nozzle won't scratch the bed, I've done it this way a thousand times and my bed looks more like new. like I said if you're not digging into the bed or moving it to the side once it's touching the nozzle there's no problem and you have actual true Z offset.

the extra step they say to do if you use the paper trick (I think PrintsLeo3D explains it well) is to measure the thickness of the paper or gauge and either put that in your slicer or simply subtract that from your current Z offset. and to check your nozzle should be touching the bed when you say it to be at Z 0.00.

so if you're a total noobie probably best to use the paper method until you're confident enough, but scratching the bed is hard once you're using this firmware, I think stock firmware don't have the sort of leveling wizard or options this has.