bed temperature accuracy

[hanktt]

Hi All,

New to the M2 family. Just had my kit assembled a couple of weeks ago and printed perfectly on my first print. I did notice that bed temperature reading is about 7 deg.C or more higher than what my IR thermometer reads. Is this a concern? Is there some sort of calibration of the thermistor used in the M2 and setting stored in the printer NOVRAM?

Thanks,

Henry

[insta]

If it's a consistent temperature, your IR thermometer is wrong. They don't do well with glossy things.

[jimc]

you will also find that the temp is not even across the surface of the glass plate. the center will be much hotter. i had done test prob 3 years ago showing the edges of the glass to be 20deg f lower than center. its really not too much of a concern. the # is just a #. eventually you will find where each plastic works best. fyi, someday if you switch to a mic6 build plate, those provide a much more even heat. 2-3deg difference at edges.

[Hugs]

For the curious...when I first got my M2, I took a thermal time lapse video of the bed heating up.

[hanktt]

Just to follow up. It turned out that I had a bad or a thermistor with incorrect value (measured 195kohm at 18deg C). At room temperature, the bad one read only 9 degC while the hotend one read 18 degC. Makegear shipped me a good one and now bed temp reads correctly. Note that the thermistor is mounted at the back edge of the bed, so the temperature at middle of bed will always be higher than set temp (unless the room temp is higher that set temp).