Bed not leveled, bad prints across bed  

Re: Bed not leveled, bad prints across bed

Slice and print the attached and upload a photo of the print.

Peter

Re: Bed not leveled, bad prints across bed

Slice and print the attached and upload a photo of the print.

Peter

Live-Z: -0.200 mm

Live-Z: -0.150mm

Live-Z: -0.100mm

Live-Z: -0.050mm

Re: Bed not leveled, bad prints across bed

Yeah, you don't need to print it with a skirt!

OK, so if the centre square is good (that's what you are aiming for with "Live Z", you can further adjust Front, Back, Left and Right using the "Bed Level Correction option in the menu.

However, there is this thread: http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/hyperfine-bed-leveling--t4330.html#p34730 which will help further, but will require you to compile the firmware (please read the whole thread... Sorry...)

Peter

Re: Bed not leveled, bad prints across bed

Yeah, you don't need to print it with a skirt!

OK, so if the centre square is good (that's what you are aiming for with "Live Z", you can further adjust Front, Back, Left and Right using the "Bed Level Correction option in the menu.

However, there is this thread: http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/hyperfine-bed-leveling--t4330.html#p34730 which will help further, but will require you to compile the firmware (please read the whole thread... Sorry...)

Peter

Thank you, i already read whole post, got a few questions:

This is correct?

This change will override any settings of XYZ Calibration or just mesh level settings?

Maybe i should up the probe, -100um looks like very near from bed and temperature can distroce readings? My ambient temperature at summer is 30ºc to 40ºc

Do you find values with G80 command or by print and try?

Regards

Re: Bed not leveled, bad prints across bed

Not trying to jump in on this thread, but you were asking about how to determine values to set with G80. I have yet to do the hyperfine leveling, but I was thinking, what if you used only one square and make 9 files that place it in the spot of each point, for instance, you have a Z file that you would print first and dial in the live z adjust for the very center of the bed. Then when that is done, you print the square only in position A, and adjust the live Z to make that square perfect. You then take that live z and determine the difference from point Z live adjust. Repeat above for each position until each square is perfect, then you are taking out the guessing of how much to adjust each position. I know you can print all 9 squares and then use calipers to get a close estimate of how much to adjust, but then you keep printing all 9 squares untill they are all good. The method I suggest, you can focus on one area, print that square quick, adjust while printing, if not good, print again quickly. Anyways, just an idea, will be annoying to have 9 gcode files, but should be easy to make using Slic3r. I could also be completely wrong in my thinking, so hope someone with more knowledge can jump in and suggest something.

Re: Bed not leveled, bad prints across bed

Not trying to jump in on this thread, but you were asking about how to determine values to set with G80. I have yet to do the hyperfine leveling, but I was thinking, what if you used only one square and make 9 files that place it in the spot of each point, for instance, you have a Z file that you would print first and dial in the live z adjust for the very center of the bed. Then when that is done, you print the square only in position A, and adjust the live Z to make that square perfect. You then take that live z and determine the difference from point Z live adjust. Repeat above for each position until each square is perfect, then you are taking out the guessing of how much to adjust each position. I know you can print all 9 squares and then use calipers to get a close estimate of how much to adjust, but then you keep printing all 9 squares untill they are all good. The method I suggest, you can focus on one area, print that square quick, adjust while printing, if not good, print again quickly. Anyways, just an idea, will be annoying to have 9 gcode files, but should be easy to make using Slic3r. I could also be completely wrong in my thinking, so hope someone with more knowledge can jump in and suggest something.

Thats a good way 🙂 Thanks for the tip i already sliced all files

Re: Bed not leveled, bad prints across bed

Yes, they are the points a to h (note: lower case).

This only corrects the nozzle height at the 8 points; it does not have any effect of calibration.

Printing the squares individually is a rather long-winded way of doing this; I can get the points correct within 3 prints of all 9.

If you look at your first 9 prints, it's not difficult to get a good estimate of the corrections required. Start with

G80 a-100 b0 c-75 d-25 e-15 f -75 g-30 h-75

Actually looks as though your live Z could go maybe -15, so do that and add 15 to the above.

Print again and apply any further adjustments.

Peter

Re: Bed not leveled, bad prints across bed

Yes, they are the points a to h (note: lower case).

This only corrects the nozzle height at the 8 points; it does not have any effect of calibration.

Printing the squares individually is a rather long-winded way of doing this; I can get the points correct within 3 prints of all 9.

If you look at your first 9 prints, it's not difficult to get a good estimate of the corrections required. Start with

G80 a-100 b0 c-75 d-25 e-15 f -75 g-30 h-75

Actually looks as though your live Z could go maybe -15, so do that and add 15 to the above.

Print again and apply any further adjustments.

Peter

Yes i used the last update with lowercase.
Do i need to recalibrate XYZ after a firmware upgrade?

I'm having big trouble here, i can't proper set the first layer live-z...
each print with same Z value comes different (Using a square at middle) 👿

Take a look at -0.300mm, they are printed one after the other
Nozzle have damaged the second -300 more than the first, and the last one looks bad
-250 have a bigger noozle scrath than first -300, not understading why!

My custom gcode changes are:


G87
G88
G80 a0 b0 c0 d0 e0 f0 g0 h0; mesh bed leveling


Re: Bed not leveled, bad prints across bed

Well, I don't re-calibrate XYZ after a firmware update, so I would think it's not necessary.

You have to remember that this is a hobby machine and perfection is not going to happen, but we can get quite close.

Different Live Z for the same result usually indicates that the probe is at a different temperature during the 9-point calibration. You need to be consistent when heating to bed with regards to probe position. Best to raise the probe to 100mm during bed heating (50mm is probably enough, but I think it depends on ambient). The probe response varies with probe temperature.

Peter

Re: Bed not leveled, bad prints across bed

Well, I don't re-calibrate XYZ after a firmware update, so I would think it's not necessary.

You have to remember that this is a hobby machine and perfection is not going to happen, but we can get quite close.

Different Live Z for the same result usually indicates that the probe is at a different temperature during the 9-point calibration. You need to be consistent when heating to bed with regards to probe position. Best to raise the probe to 100mm during bed heating (50mm is probably enough, but I think it depends on ambient). The probe response varies with probe temperature.

Peter

I found the reason why first layer always come different.
It was from the e3d hotend sock i have installed, somehow the fillament was grouping inside sock without my knowledge, i always look at nozzle and the tip was always outside the sock, align with hole, but... Anyway sock was made to keep hotend clean, but now is all dirty 🙄
I already clean and run some test, first layer at center comes good now, still have to align bed now with modified firmware.

Thanks for all the help

Re: Bed not leveled, bad prints across bed

Ok, now i getting somewhere, still i can't get it perfect. "A" doesn't like me

My config:
Live-Z: -0.190mm
G80 a-120 b20 c0 d0 e0 f0 g0 h-100; mesh bed leveling

As other params are all 0 i'm not sure if change them will affect "A"
Any suggestion?

A

B

C

D

E

F

G

H

Z

Re: Bed not leveled, bad prints across bed

Theoretically, changing one point should not affect the others, but I do know that the interpolation of all points in between will vary.

I suppose you could go a little lower at "a" but as part of it looks OK, you may not get any better than you have, and you are not going to be printing in that part of the bed very often.

Peter

Re: Bed not leveled, bad prints across bed

Theoretically, changing one point should not affect the others, but I do know that the interpolation of all points in between will vary.

Still when i change "b" print quality of A improve dramactly, almost get a perfect "a", after i change "h" and "a" quality end on this last print i shown here

I suppose you could go a little lower at "a" but as part of it looks OK, you may not get any better than you have, and you are not going to be printing in that part of the bed very often.

Peter

The problem is "a" have a big distortion, Upper left comparing with bottom right is a huge difference, how is that possible in such small area?
I will try lower a bit but nozzle already scrath the bottom right "a"
And yes i almost never use that side, but if theres an option to fix it i will be on it 🙂

Also i like to understand what happen with the printer, because it print well before, even big surface parts. I have it for about a month and suddenly this problem apper to me. The only change was the ambient temperature, it goes from 20ºc to almost 40ºc (summer temperature here)

Re: Bed not leveled, bad prints across bed

These is a problem with the calibration squares in that they don't print at precisely the probe points and of course they should just be a single point, again to match the probe points.

I think what you may be experiencing at point "a" is a combination of bed level (or not) and interpolation.

Not sure ambient is causing the problems (I also have big swings for 18 to 38 degrees in my office); a small change in Live Z may be necessary for seasonal differences, but that's about all.

Peter

Re: Bed not leveled, bad prints across bed

These is a problem with the calibration squares in that they don't print at precisely the probe points and of course they should just be a single point, again to match the probe points.

I think what you may be experiencing at point "a" is a combination of bed level (or not) and interpolation.

Not sure ambient is causing the problems (I also have big swings for 18 to 38 degrees in my office); a small change in Live Z may be necessary for seasonal differences, but that's about all.

Peter

Thank you for all the advices and the firmware change, this should be merged into official firmware with use of LCD menu with all points. Talking about LCD, is it possible to disable backlight from firmware? I only found commented sections about it and they are for old hardware versions...

I'm now fine tunning the values, once i got the best result i will post here and try print some test models.
Regarding Live-Z, imagine if i lower value by 10, i need to add 10 to all G80 values right?

EDIT1: Best setting for me: "G80 a-170 b35 c15 d0 e0 f5 g-15 h-95; mesh bed leveling"

Regards

Re: Bed not leveled, bad prints across bed

Talking about LCD, is it possible to disable backlight from firmware?

Not that I am aware of; I don't think there is any switch and other similar LCDs I have are the same. Upgrading to an OLED may help - it's been done and there are notes in the "Improvements section I think.

Regarding Live-Z, imagine if i lower value by 10, i need to add 10 to all G80 values right?

Yes.

Peter