Jog Z? Is it possible?

Is it possible to simply jog the Z axis up and down? I’m experimenting with a lot of different alternative leveling schemes and it’d be very helpful if I could just move the printing surface up and down a bit. Does setting the bed height in advanced settings just move the bed to that spot (so I can use it like a jog) If I switch it from 1808 to 1500 then 1600 will it simply move to those coordinate or does it home or do all sorts of silly stuff like that?

Not at this point in time. I’ve asked for this since last July.

The Z reset is the distance from home to the Z zero build height. If you set the Z reset to 1500 it will move down 150mm and if you leveled the vat at 1877 the build plate will be about 37.7mm away from the vat.

Have you read the following topic?

I actually have, thanks! Does it home between adjustments? that would get annoying, otherwise, it’s basically a jog setting, if I can adjust it up or down and it’ll just move where it’s told…no?

Now that I’m back with my machine and tried jogging the Z using the bed height adjustment, I see very much why we need a dedicated Z jog setting. Consider this a feature request Peopoly, why on earth isn’t this already a thing.

Thank you for your feedback. We like to mention that leveling is not something needs to be frequently done and does not need to be precise like FDM printing. Once you have it in around corners that can apply enough pressure to PDMS to get 10.7mm on the DIY-test print, it can handle a good variation up to ± 0.3mm in PDMS layer height. That is one of the reasons why PDMS is used. Some of the very heavy Moai users like Evan Morgan runs his 2 Moais almost none stop, and he leveled like once since he got Moai back in last June. And he did it because I asked him to check my new leveling guide and not because something wasn’t working. You don’t need to hit the perfect level pressure on PDMS to get the best print possible because of PDMS self-corrects after couple layers. You do want to make sure your recoating follow the vat restore guide
In fact, we have stopped telling the user to level when they build Moai for the first time because Moais are pre-leveled out of the factory before disassembled for shipment. They just need to check leveling and make quick corner adjustments, and it is leveled.

Z-jog wouldn’t be as useful because most of the leveling problems are uneven pressures from 4 corners.

The thing is, for me, jog would be useful, I know, because yesterday I wished I could do it. I’m devising many better ways of leveling, and I’m also prototyping an improved Vat. My vat uses both PDMS and FEP. So when people are tinkering with new ideas for the moai, being able to move the buildplate around is very helpful!

Yesterday I leveled my bed by raising the height to the top of the vat, laying a thick sheet of glass across the top of the vat, and adjusting the screw till the glass barely touches the buildplate on the 4 corners, then resetting the Z. It worked perfectly but would have been much easier to line up if I didn’t have to use the z height setting to move the buildplate where I want it to be. Myself and many others are working on improving this printer, and being able to move the Z is critical to a lot of our projects.

The thing is, you don’t want the plate to be “barely” touching the corners. That is FDM leveling approach for top-down printing. That type of leveling can have problems for larger prints and small differences in vats for bottom-up SLA printing as it does not give a good adhesion on the build plate.

What you want in bottom-up SLA printing is for the build plate to be pressed into PDMS so that it can make an 11mm cylinder into 10.7mm for good adhesion. And the only feasible and objective to do that is to print the cylinders.

And you can move build plate height with the z-reset position.

Maybe I didn’t full understand and let me get back when it is daytime here. We always appreciate feedback and we share them with the development team.

Yeah you’re not following. It’s ok. I’m not leveling the buildplate to the bottom of the vat barely touching. I’m leveling the buildplate to the TOP of the vat barely touching (just so I know it’s even) then setting the z offset so it’s digging into the pdms a little. I’ve gotta solid results like this. It makes sure the buildplate is square to the vat itself, but doesn’t account for variation in pdms. It’s good enough for me to check my level without having to drain the vat.

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sounds like a really good way to get things leveled. Would be easier for sure if we could just slide the z up and down on the fly in that case.

Can you assume that the top of the vat is perfectly parallel to the level of the PDMS?

If not, then leveling to the top of the vat will not necessarily be level at the PDMS.

I pour my own pdms and I’m positive they are level…Plus I’ve been leveling this way for about 2 months without problems