Fine-Tuning Bed Leveling
So... I've done the nylock mod a few months ago, and had the bed almost perfectly level (on a cold bed).
I didn't touch the printer for a couple months, and tried printing, but then I had an error that said, "Some problem encountered, Z-leveling enforced". So naturally, I googled it and from what I read, I came to the conclusion that I should check my bed leveling values again. One corner was off by .95 (raw). Not sure how it happened, but I made changes and readjusted and finally got everything back to only 0.01 (raw) difference.
Anyways, I then remembered that I read that the temperature of the bed will change the values. So I thought, let me change the bed temp to 65 (as an average temp) and re-run the bed leveling. My numbers were WAY off from the cold bed values. And 65 is conservative. What if I did PETG where some settings recommend a temp of 85?!?!
So I guess my question is, when I'm fine-tuning bed leveling, should I be doing it with a warm/hot bed or with a cold bed?
Here are my COLD Bed results:
Recv: 0.15333 0.15333 0.17083 0.15250 0.15833 0.13833 0.14667
Recv: 0.14000 0.16583 0.15417 0.12167 0.12000 0.16333 0.15667
Recv: 0.14583 0.15667 0.15917 0.14354 0.13750 0.18000 0.15833
Recv: 0.14667 0.13000 0.10833 0.15583 0.13979 0.13417 0.14917
Recv: 0.15333 0.15167 0.14417 0.14042 0.13167 0.16833 0.13667
Recv: 0.13750 0.16333 0.16667 0.13000 0.12500 0.17333 0.13750
Recv: 0.15750 0.18667 0.19833 0.15583 0.17083 0.18167 0.14917
Raw values:
0 0 -0.01
-0.01 0 -0.01
0 0 -0.01
Degrees:
0°CCW 0°CCW 7°CCW
7°CCW 0 7°CCW
0°CCW 0°CCW 7°CCW
Fractional Turns:
0CCW 0CCW 0CCW
0CCW 0 0CCW
0CCW 0CCW 0CCW
Here are my results at 65
Recv: 0.11750 0.14417 0.16833 0.16000 0.15750 0.13917 0.13583
Recv: 0.13500 0.19333 0.19250 0.16750 0.15917 0.19833 0.16083
Recv: 0.15917 0.21000 0.20500 0.18958 0.18500 0.22250 0.15917
Recv: 0.15667 0.17750 0.15750 0.20083 0.18646 0.18333 0.15750
Recv: 0.16833 0.20667 0.20833 0.19250 0.17667 0.21167 0.13833
Recv: 0.14417 0.21333 0.22167 0.18417 0.18167 0.20417 0.11833
Recv: 0.12083 0.18750 0.20333 0.16167 0.17250 0.16250 0.08000
Raw values:
-0.08 -0.04 -0.06
-0.04 0 -0.04
-0.08 -0.04 -0.12
Degrees:
58°CCW 29°CCW 43°CCW
29°CCW 0 29°CCW
58°CCW 29°CCW 86°CCW
Fractional Turns:
1/5CCW 1/10CCW 1/10CCW
1/10CCW 0 1/10CCW
1/5CCW 1/10CCW 1/5CCW
RE: Fine-Tuning Bed Leveling
[...] So I guess my question is, when I'm fine-tuning bed leveling, should I be doing it with a warm/hot bed or with a cold bed?
In general, enable 7x7 mesh bed leveling in the setup menu and see if you actually observe a problem. In addition to temperature fluctuations, the print surface itself is removable by design and so will tend to change in use. I'm using the Prusa bed level plugin for OctoPrint and see a bulge move around the right side of the bed over time, varying in degree and position. With 7x7 mesh bed leveling, it's never been a problem. If it becomes a problem, I'll look at the nylock mod to move within tolerance, but even then won't worry about small variations.
RE: Fine-Tuning Bed Leveling
So then what is considered "within tolerance"? Are the values that I have considered "small variations"? To me they seem like large variations.
RE: Fine-Tuning Bed Leveling
So then what is considered "within tolerance"? Are the values that I have considered "small variations"? To me they seem like large variations.
The working definition for in tolerance for me is small enough not to produce visible defects. If I can print a square and it comes out even across the surface and smooth on the underside, that's about as good as I can hope for. A lot of the emphasis on perfectly flat beds you find on the Internet relate to printers without mesh bed leveling, so all the work is necessary to get a good even flat surface. Provided your print surface (note: the surface, not the bed) isn't too far out of whack, mesh bed leveling can compensate and produce a good even flat surface. That's part of the reason I paid more for a Prusa with these features, along with the removable spring steel surface. YMMV of course, but I wouldn't worry about the numbers so long as I'm getting good finish with 7x7 mesh bed leveling enabled.
RE: Fine-Tuning Bed Leveling
@bobstro
Thank you for your replies.