MK4 vs MK3S+ bed temperature difference
Summary: To reach the same bet temperatures, you need to increase the MK4 bed temperature of 4-5C
I have been very happy with my MK3S+, however I have to say the MK4 is way below my expectations so far....hopefully by updating the FW a few more times, this new model will behave the same or better of the old one. I have been having warping from the prints and I decided to take a close look at bed temperature between the two printers. I took an infrared temp gun and made some measurements. I was pretty surprised by the results, the MK3 behaves better!
First I looked only at the center of the bed, see the results below. They both do not really reach the set point (and that is fine), but the MK4 is worse than the MK3
Bed Set Point 105C : MK3S+ = 101C | MK4 97C
Bed Set Point 115C : MK3S+ = 112C | MK4 108C
There is a 4C consistent difference at those temperatures, so I decided to set the MK3 at 115C and the MK4 at 119C and I measured 9 points on both plates:
MK3 MK4
Top Left. 105 102
Top Middle 112 108
Top Right 104 100
Center Left. 108 106
Center Center. 112. 111
Center RIght 106. 104
Bottom Left 96. 104
Bottom Center 113. 111
Bottom Right 100. 104
The 9 temperature are more consistent with these 2 settings, I think I can inscrease 1C the MK4 too to reach the same.
That being said, I am pretty disappointed by Prusa. The MK4 is not up to the previous standard
RE: MK4 vs MK3S+ bed temperature difference
That explains why the factory preset for extrudr DuraPro ASA wasn't working for me... With a set point of 90°C, the MK4 build plate wasn't reaching even close to that...
RE: MK4 vs MK3S+ bed temperature difference
This is crazy to me, I wasted so much filamente before increase the temperarture as well....I am pretty disappointed about this. The MK4 is not a real upgrade from the MK3
RE: MK4 vs MK3S+ bed temperature difference
in my printer heatbed temp. is below some 15 to 20 degrees comporing to the set temp. in the settings... it took me a while, and few disasters on plate to figure it out... thermistor is on a way for replacement (i alredy got spare thermistor for hotend which was also broken). Now, since i learned that i have to increase the temp +20 for the plate, i print PETG without issues.
RE: MK4 vs MK3S+ bed temperature difference
in this topic you can check how much the plate temp. can be different between printers:
RE: MK4 vs MK3S+ bed temperature difference
In my case, considering the offset is ~5C, I think this is more likely to be a sensor calibration. They mapped the sensor wrongly or the sensors they used in production are not exactly the same of the first ones they developed the printer on....who knows? Either way this is not acceptable
RE: MK4 vs MK3S+ bed temperature difference
Hi, just to update, i replaced last night the heatbed thermistor, and now the reading is much more accurate. I measured the resistance of the thermistor and the difference was around 20k Ohm in the room temp, so the "old/broken" had around 103k Ohm, while the "new/working" 80k Ohm. First print tests, and reading with pyrometer, and thermal vision camera showed the drift around 10 degrees, not 20 like before, and in higher temps. it's better.