Good news Higher density mesh bed leveling coming  

Re: Good news Higher density mesh bed leveling coming

OTOH, maybe Prusa sees this as a solution to poor yields on their textured sheets.

Mesh bed levelling is not going to make any difference if this is the case since the PINDA works on the flat steel sheet not the PEI surface coating.

From my experience, most of the irregularity requiring mesh bed levelling comes from the heatbed which flexes as the temperature changes and not the textured PEI sheet.

Now if the Calibration Bed level correct points were increased to match the 7x7 or 9x9 quantity, that would be a complete new ball game and allow for perfect first layers, but I don't think there is enough memory capacity to be able to do this unless PRUSA find some way of maybe storing the lookup table on say the SD card.

Hmmm, If there is a yield issue with irregular thickness of the coating, then if an SD compensation map file were used, then each sheet could be sent out with a QR code which has a link for the compensation map for the surface, this could then be downloaded to the SD card.
3rd party sheets would not have this, so would be less desirable.

However, if the coating is uneven on the bottom side of the build plate it will affect the flatness of the steel sheet which will effect the PINDA readings... The surface of the PEI stickers are uniform and the powder coating is much more difficult to maintain a uniform thickness across the sheet. At least I'm assuming surface uniformity is what's causing poor yields on the PC sheets. I know the two after market PC sheets I own have high and low spots on them and the 7x7 makes a world of difference to the first layer on them.

Re: Good news Higher density mesh bed leveling coming

Are you guys really suffering from the current levelling? I fully agree it's always better to have a perfectly levelled bed but I'm using always 0.2mm for the first layer and was never a big thing for me.

Yes, especially when you have to fill and entire build plate of prints to fulfill orders that require an immaculate and consistent first layer

This picture is a print that’s still in the dialing in phase. There’s still some imperfections that were being fixed:

Here’s an example of a print that required a perfect first layer that I dialed in:

Re: Good news Higher density mesh bed leveling coming

Can you set different layer heights using Slic3rPE ?

Yes, first layer and other layers can be set differently in Slic3r PE. Most of the slicers allows it.

Re: Good news Higher density mesh bed leveling coming

Here’s an example of a print that required a perfect first layer that I dialed in:

That photo is blurred, so it's hard to say anything about the layer quality.

Re: Good news Higher density mesh bed leveling coming

Here is a good example of the benefit of 7x7 vs. 3x3 leveling.

As you can see, the outer points are all pretty level, so when you look only at these and interpolate in between, you totally miss that bump in the lower right corner. I always have that bump, even if I measure multiple times and rotate the sheet.

I leveled the bed with the screw mod, but I can't remove this bump. Hopefully, it will be fully compensated for by the firmware.

Re: Good news Higher density mesh bed leveling coming

I leveled the bed with the screw mod, but I can't remove this bump. Hopefully, it will be fully compensated for by the firmware.

You have less then 0.1 variance through the whole bed. Most people just dream of that 🙂

Re: Good news Higher density mesh bed leveling coming

Here’s an example of a print that required a perfect first layer that I dialed in:

That photo is blurred, so it's hard to say anything about the layer quality.

That’s actually not a blur. That’s the light reflecting off of a completely solid looking first layer. Here’s a picture from another angle

Re: Good news Higher density mesh bed leveling coming

much better picture, at least we can see lines now 😀 thanks

Re: Good news Higher density mesh bed leveling coming

Without that last picture, I was totally amazed at how you managed to remove such a large, perfect, thin sheet from the print bed.

Re: Good news Higher density mesh bed leveling coming

as long as its a few layers just let the build plate cool. they come right off

Re: Good news Higher density mesh bed leveling coming

That’s actually not a blur. That’s the light reflecting off of a completely solid looking first layer. Here’s a picture from another angle

It actually is blur. You can see that the camera focussed on the backround, which is sharp. The finger next to your first layer, is totally blurred.
But your new two photos are very nice!

Re: Good news Higher density mesh bed leveling coming

Is there any way for me to try this without joining FB? I don't have an account.

Re: Good news Higher density mesh bed leveling coming

Is there any way for me to try this without joining FB? I don't have an account.

There are multiple variations in this thread, pick your poison...

https://github.com/prusa3d/Prusa-Firmware/issues/1239

Re: Good news Higher density mesh bed leveling coming

Refining the bed leveling routine sounds promising
Possibly that partially explains why ABS prints consistently lift on the left hand side of bed.

Print Setup:
Initially located the print in the middle of bed. Print lay flat size 5 (127mm) x 3 (76mm). Filament MakeShaper 1.75mm ABS. Nozzle 0.45mm. Started with Slic3r PE recommended settings for ABS. Built an enclosure around three sides of the printer 24 (610mm) width x 24 (610mm) depth x 24 (610mm) tall, cleaned PEI sheet with Acetone, Alcohol, Windex glass cleaner (no improvement)

Purchased a Fluke model 62 Max + temperature sensor and mapped the surface temperature of bed. The temperature variance across the surface in my opinion is considerable.

Bed Temperature Measurements (temperature setting 100C)
Rear left to right 97, 100 96
Center left to right 101, 99, 97
Front left to right 99, 102, 98

Bed temperature variance 6C

Orienting the part in areas of the bed with a more constant temperature reduced the amount of lift.
Increasing the bed temperature 10C reduce the lift further (above the recommended value)

Are there other techniques that I should be exploring to resolve the lift problem?
Thank You,

Re: Good news Higher density mesh bed leveling coming

7 x 7 Mesh Bed Levelling now released in the new 3.7.0-RC1 Firmware, available on the GitHub site: https://github.com/prusa3d/Prusa-Firmware/releases/tag/v3.7.0-RC1 .

Re: Good news Higher density mesh bed leveling coming

7 x 7 Mesh Bed Levelling now released in the new 3.7.0-RC1 Firmware, available on the GitHub site: https://github.com/prusa3d/Prusa-Firmware/releases/tag/v3.7.0-RC1 .

I was wondering when we'd see an RC with that feature... Guess I know what I'm doing once my current print finishes... 🙂

Re: Good news Higher density mesh bed leveling coming

Am I the only one getting crash detected errors with the 3.70 RC1 firmware as a mesh bed level and completes?

Re: Good news Higher density mesh bed leveling coming

I I think I found the problem my noctua fan wires weren’t tucked in all the way.

Re: Good news Higher density mesh bed leveling coming

I'm getting a forced z calibration in middle of the mesh bed leveling process at random points after updating to this firmware. This is happening to 4 of my 8 printers. Everything was fine before. Any ideas?

RE: Good news Higher density mesh bed leveling coming

Posted by: michael.p55

I'm getting a forced z calibration in middle of the mesh bed leveling process at random points after updating to this firmware. This is happening to 4 of my 8 printers. Everything was fine before. Any ideas?

Have you updated to the released version of firmware? The first beta version posted gave me the same problem until I set the number of samples for each point to 1. The released version operates with 3 samples but if the first fast sampling fails on a point (too much variation between each sample) it falls back to the older slow sampling method for that point, this allows any vibrations to settle down a bit before the next sample.