Uneven heat distribution of print bed
Hi.
Just for fun I borrowed a thermal camera from work and took a picture of the print bed of my Mk3S. This is what it looks like at 60° C:
The temperature varies from ~54-57° C. This is with the PEI steel sheet on.
Is it normal with this big variation in temperature across the print bed?
Is it also normal that it doesn't reach the set temperature (60° C) at any point on the bed?
RE: Uneven heat distribution of print bed
As far as I remember FLIR cameras have up to 5C accuracy. Without proper calibration and reference value, your 57C measured temperature is just a guess. The variance of only 3C across the bed is pretty good. Depending on the environment you might get a better or worse result (cool breeze vs enclosed)
Thomas did a comparison between different beds. Might be interesting for you:
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
RE: Uneven heat distribution of print bed
Very interesting couple of videos. Thanks for the tip.
The accuracy of our particular FLIR camera is 2º, but it looks like my values are very close to what Thomas got.
The picture I took was taken immediately after the printer reported reaching 60º. I think I'm going to borrow the camera again and see what the bed looks like after letting the heat settle for a couple of minutes.
RE: Uneven heat distribution of print bed
I got similar results as you. At the hottest spots, my camera read about 2°-3° lower than the temperature indication on the front panel. Waiting a few minutes after the temperature stabilized, about 1 cm in from each corner, the temperature was a full 10° lower than the hottest areas. Everywhere else the temperature was pretty even, with a small spot in the exact center being 4° cooler, and also 4° cooler about 1 cm from the edges.
This might explain why I've had warping issues for a long object that used the full diagonal length of the build plate. I fixed the problem with a "helper disc" in PrusaSlicer, and now that I have a thermal imaging camera, I can see why it happened: the build plate was only 50° in the corners.
Because I am trying to wear my plate evenly by printing stuff all over the place instead of always in the middle, I think I should raise my bed temperature 5° for things I print near the edges, and I need to stay away from the corners.