Brim - Global Z-height Bug

[ccavanaugh]

Not sure if this is considered a bug or a feature, but if the global z-offset is negative and it exceeds the first layer height including the multiplier, then the brim/skirt is effectively disabled. My expectation is that a brim/skirt would still be generated.

[CompoundCarl]

If your layer height is 0.2mm, and you have a z-axis offset that is lower than -0.2mm, most users would actually ram their print head into the build platform! It's really dangerous to do that. So I'm actually surprised S3D even allows you to print like that. I would almost expect them to prevent that entirely since there's so much risk of screwing up your printer.

You should probably level the bed a bit better

[ccavanaugh]

Agreed it's best done in firmware.

I prefer to adjust it in the slicer until I find the ideal height, and then zero and update in the firmware. It just saves the hassle of updating config files/eeprom etc. (PC is not connected to the printer). Kisslicer and Slic3r behave as expected when I enter a negative Z offset.

In this instance, I took my first stab at using BuildTak and overshot the increase in my bed thickness by a bit and stumbled on this behavior during a couple of calibration prints.

[dkightley]

Before we go too far on this.......I've noticed that if you have a negative z offset where the height of the brim/skirt is less than the z offset, then the brim/skirt will not be visible in the preview if you're looking from above......the virtual build plate gets in the way!

Rock the view so you're looking from below the build plate....and you can see the skirt/brim.

Could this be the "perceived" error.....and it not be an error after all?

[ccavanaugh]

Before we go too far on this.......I've noticed that if you have a negative z offset where the height of the brim/skirt is less than the z offset, then the brim/skirt will not be visible in the preview if you're looking from above......the virtual build plate gets in the way!

Rock the view so you're looking from below the build plate....and you can see the skirt/brim.

Could this be the "perceived" error.....and it not be an error after all?

You are correct.. I see it now. I did not think think to look under the bed for the skirt. Thanks!

[dkightley]

I'm glad about that.

I only realised this might be the problem earlier today when I added a brim...and I couldn't see it in the preview. And then the penny dropped!!

More of a "Duhhhh!" moment than a "Eureka" moment.......

[UlrichKliegis]

You are correct.. I see it now. I did not think think to look under the bed for the skirt. Thanks!

Better than the other way around...

scnr,

Cheers,
U.