I usually print ABS and ASA filament, i found that K1 Max has a lot of positive characteristics but passive heating of chamber results in more than 20 minutes lost waiting and chamber temperature that not grow more than 40° celsius. i think that a kit with active heating of chamber in order to reach stable 60-70° will be welcome and foundamental for good layers adhesion of high temperature filament. in my opinion Infrared heater could be something new compared to competitors.
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The K2 Plus was announced with a heated build chamber. I’m not sure if all parts in the K1 Max are suited for 70°C chamber temp, especially the extruder already runs a bit hot without it.
i’m not sure too. passive heating of bed at 110° at tropical climate i think that chamber reach 50-60° ; the problem is not the extrusion but in a tall piece temperature differenes from bed to top causes delamination and poor adhesion.
i will try two (to cover shadow) external infrared lamp and thermal map to measure gain
I have printed almost 20kg of high temp Overture polycarbonate now. Hotter chamber is better. To do this, set bed temp to 110C, extruder to 180C or whatever is a sub-oozing temp, home the Z so it lifts up as high as it can go, and turn on extruder and side fan but not the exhaust fan. This makes it preheat up really fast, but I wait for 40C at least to start, or preferably close to 50C, then print with the side and exhaust fan OFF (and polycarbonate is usually printed with the extruder fan off too, except when printing short layer times the fan may be needed, but slowing down the layer worked better for me). Without the side fan blowing across the bed, the temp rise will be slower but the temp still keeps increasing
However- stepper motors’ max torque curve shifts down with temperature. That’s just diminished magnetic permeability of the iron core, it’s got no long-term effects. But the motors’ capabilities were not calibrated for this weakening.
What I discovered is that at about 60C, if you still have the machine configured for high speed and high accel, this may exceed the motor’s available torque and a stall results. The machine will not be aware that the motor is in the wrong place and continue building over the wrong part of the bed and can bang into the endstops sometimes.
It resembles loss of bed adhesion, but the dead giveaway is the work is still adhered to the bed yet the print still shifted over. With the exhaust and side fan left off and the printer printing, the chamber can eventually get about 33C above room temp but that will take some time. So it’s more likely to happen if the room temp is high (>25C) and it’s been running for over 45 min.
I did see a pic where someone made a duct to route the side fan to blow UNDERNEATH the bed to circulate its heat. This is an interesting concept, except I don’t think it had any way to adjust the air path as the bed drops.
Instead of adding a new heater and find some extra power to run it, simply adding auxiliary fans on the bottom of the bed should give plenty of chamber heat. The build plate has lots of extra wattage, it should have no prob holding 110C.
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Thank you so much for the valuable information.
The parameterizations of the initial setup are very interesting, i think it could be useful to create a macro that does all these activities.
The motor torque curve that changes with temperature is something I didn’t take into consideration, now perhaps I understand why some upgraders also propose to replace motors and belts.
Thanks to your parameters I noticed a defect for which there was an hidden default of 35° of the chamber (firmware creality k1 max) and my slicer (orca) settings was set 0° (i.e. not to manage) so it happened that at a at a certain point the chamber emptying fan starts which removes heat (through carbon filter). Now I have explicitly set 50° in the slider as the chamber temperature ( no wait temperature for start and no active ), in this way I went up from 41° to 45.2° but now i imagine that with insulation I can go up a little more and reach 50°.
I also saw the modification that blow the bed, i’m not convinced as you for the same reasons cause having a high chamber temperature is necessary as the bed descends, because the lower part of the piece being printed continues to be heated by the bed and the upper part by the head , problem is in the middle part that have to maintain the right level of softness and temperature to prevent retraction.
thanks againg
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The 110C bed will definitely continue to heat the chamber as it descends below the side fan.
Now that summer is here, I have seen the chamber temp continue to rise while printing if the exhaust fan is off. Or, when it got pretty warm in that room, temps climbed to close to 60C.
I was seeing jams I attributed to heat creep when the chamber got to ~60C with PET-CF. I’m not certain though if this was really causing the jams.
If we needed to mitigate chamber heat probs, you’d probably just glue water heating blocks to the steppers. And if you’re doing that, water cool the heat brake too.
You DO want to run Input Shaping with the chamber heated to that temp, as well as calibrate the bed mesh while the bed is hot.
Those belts are going to be significantly different at high temp. They’re real clear you must calibrate IS when you move the printer, and not have anything touching it- but missing the obvious. Those belts are going to have notably different elasticity and dampening at 50C!
Unfortunately, I don’t think IS can be set with different cals for different temps, you’d have to reload a saved cal manually when you change temps
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This is an excellent discussion, thank you. After installing a relatively powerful blower to exhaust fumes, my ABS prints started failing due to warping. I then measured a drop in chamber temp from 50° C without exhaust blower, to 35° C with exhaust blower.
I’m now exploring various options to heat the chamber, including some mentioned here.