Build Plate Temperature Uniformity (Issue?)
Does anyone know how much variation we can expect in the temperature across the build plate ?
For context - with long prints that span the full build plate, I get pretty consistent warping off the left side of the plate.
Today, I checked the temps on build plate with an IR thermometer at various points across the plate after heating to 90C.
What I found is that the center six squares on the plate read 88C +/- 1.5, with the two dead center trending lowest (not terrible).
The left most center two read about four degrees lower than that, or 84.5C +/- 1.5, while the right most center two read much lower at 76C +/- 2 80 +/- 2.
The front left and right most have the most variance from set temperature, and the most fluctuation, with the right most being the worst - 74C +/- 5(!!)
Is this expected behavior or am I seeing an issue with my heat bed ?
If this is expected behavior, how do others compensate to avoid warping? The obvious approach - printing dead center - is not always possible and drastically reduces effective print volume.
NB: All measurements 50 CM off build plate with no steel sheet.
Best Answer by Artur5:
Temperature variance across the bed depends on several factors.
First the differential between room and target temperatures. Obviously, higher bed temperatures imply more difference with the room and hence more variance across the bed from center to corners.
Second factor : Enclosure or not (and the thermal insulation of the enclosure, if you use one ).
Your values aren’t bad provided the printer isn’t enclosed, which I assumed it isn’t because you didn’t say, but maybe I’m wrong ?. If there’s no enclosure at all, try to avoid drafts around the machine.
You could take the temperatures with the steel sheet installed and compare the results with the values without steel plate. Possibly the metal will contribute to equalize better the heat across the bed, but I wouldn’t expect a significant difference.
Prusa is MK4S w/ MMU3 (formerly MK4 / MMU3, MK3S+/MMU2), 2 Prusa MINI+, Octoprint. PETG, PVB, (some) PLA.
RE: Build Plate Temperature Uniformity (Issue?)
Temperature variance across the bed depends on several factors.
First the differential between room and target temperatures. Obviously, higher bed temperatures imply more difference with the room and hence more variance across the bed from center to corners.
Second factor : Enclosure or not (and the thermal insulation of the enclosure, if you use one ).
Your values aren’t bad provided the printer isn’t enclosed, which I assumed it isn’t because you didn’t say, but maybe I’m wrong ?. If there’s no enclosure at all, try to avoid drafts around the machine.
You could take the temperatures with the steel sheet installed and compare the results with the values without steel plate. Possibly the metal will contribute to equalize better the heat across the bed, but I wouldn’t expect a significant difference.
RE: Build Plate Temperature Uniformity (Issue?)
@artur5 You called it - I have a print chamber (larger than the standard prusa enclosure, and freestanding) which was open at time of test.
Looking at the temps in the chamber during print, it seems like I will need to bring back my heater.
Thank you!
Prusa is MK4S w/ MMU3 (formerly MK4 / MMU3, MK3S+/MMU2), 2 Prusa MINI+, Octoprint. PETG, PVB, (some) PLA.