Thick bed temperature controll

[Erhytr]

I browsed the forum more and found one more thread with the same issue:

Feature idea: bed temperature loss compensation

Hi All. The bed temp is often 10+ degrees off from that the bed sensor temp says. And the bed surface sensors are rare and far apart. So instead of adjusting all my material settings 10 deg up, I would rather have a printer config for that. I’m thinking along the lines of: calibrate temperture drop per degree delta. Likely a table of common values for common stacks can be created. capture the ambient temp before heating starts, if you have a chamber sensor, use that. dynamically compute the…

And honestly, I’m a bit frustrated. Looks like we have an issue that is unsolvable without changes in the code, or going deep into the hacks.
And it’s not a new one. People proposed the solutions, opened PRs, (one more) even did such awesome simulations:

Feature idea: bed temperature loss compensation

I have created an open source heat bed thermal emulator/simulator that is reasonably accurate. It illustrates many of the issues that are described in this topic. It takes conduction, convection and radiation into account similar to your calculations above. Maybe it can be of use to you for making approximations. https://monkeypangit.github.io/thermalemulator/ [thermal_emulator] It runs in your browser without any need to install anything. The source code can be found on github: My own con…

But at the end of the day, the issue was considered insignificant, fix not really useful, and configuration hard for user to setup.
I’m not blaming or saying that it’s useless, but we have features with couple pages size description, that requires configuration and calibration, and all that is just to squeeze out a couple of microns better accuracy out of endstop.
At the same time 10%+ error on bed temperature, and possible like 30% improvement on heat up time is not considered important enough. And all that is on pretty common setup.
I think most people just don’t notice it, because the second thermistor on the bed is not that common, but not having it, doesn’t mean the issue doesn’t exist.

I don’t know it all the suggestions were valid, and PRs was good to merge. I just want to bring the attention to the issue, which in my opinion, is very real, and fixing it may benefit many people.