Mesh bed leveling skeptic

I have a very seasonal confession. I was a skeptic of the need for mesh bed leveling (gasp).

However, I share an image with you that makes me a believer. It is a photo of the bottom of a 150mm x 220mm raft. The longer direction is in the Y-Axis.

From this, you can see that the first layer is thicker in the middle (lines are thicker horizontally which means they are more squished there and bed is higher in Z direction) and thinner at to top and bottom -- this tells me that the 3mm aluminum build plate that is at a temp of 115 degC is bowing up in the middle and is lower at the edges.

Also, from left to right, you see that the layer lines get thinner from left to right -- I have an issue with tilt either from the bed or from the two z-axis screws in relation to one another.

So clearly, bilinear mesh bed leveling is needed to compensate for this.



Edited 1 time(s). Last edit at 04/04/2021 10:38AM by NovaHuta.

Or you could use a bed that doesn't turn into a potato chip when you heat it up and/or use a properly aligned Z axis.

Sensors and software can fix a lot of problems, but if one of those fails, can you still print? Quality construction and proper alignment "just works", every time.

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Son of MegaMax 3D printer: [www.instructables.com]
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I am an antiseptic

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"A comical prototype doesn't mean a dumb idea is possible" (Thunderf00t)

A messed up bed can be improved by putting a flat glass layer on top.

The tricky part is clamping it on securely. And being able to unsecure it.

This is where a moving bed makes things easier to tweak, if you can adjust the level of the corners and moving edges.

Am loving having autocalibrate. But have printed without it. Just more trial and error.

Flat glass on an unflat bed will not heat evenly, so you may have problems with getting prints to stick.

I am amazed at the effort people put in to understanding how to get autoleveling and flatness compensation working compared to the effort they put in to understanding how to build the printer in the first place. It is entirely possible to build a printer that does not require autoleveling or flatness compensation (many have done so, including me) and no trial and error when printing. You won't see such printers in youtube videos because it's boring to watch a printer that just prints when you tell it to, but it is very nice to use one.

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Son of MegaMax 3D printer: [www.instructables.com]
Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]