I remain impressed with the Zero’s passive heating. The passive heating on this small enclosed printer is significantly better than my previous experience with passively heated chambers on larger printers. I’d be more interested in chamber pre-heating if I was printing tall thin walled objects that warp a lot and grow in height so fast that the chamber doesn’t have much opportunity to heat while the base is printing, or if I was printing with more exotic high temperature materials that are more difficult to print. I am thinking of buying a spool of PPS in case I need some very high temperature parts.
I abandoned my initial idea to print low infill foaming PLA-LW thermally insulating tiles for the inside of the Zero when I saw how quickly the chamber heated without insulation but this thread indicates interest in faster and more effective passive chamber heating. It wouldn’t be difficult to print some insulating tiles. I already have the PLA-LW filament and the magnets. I’d follow bircoe’s good example and provide graphical data showing the chamber heating with and without the thermal insulating tiles… because I’m an engineer, and engineers love data! The tiles wouldn’t interfere with the Zero’s range of motion or operation, other than making passive heating more effective. For me, that would only mean that the exhaust fan would turn on sooner when the chamber reached 60 C… or 50 C for PETG. The Zero would be more energy efficient, it would dump less heat into my office, and it would be quieter. It would make PLA cooling slightly more problematic but I don’t print high speed PLA. As an added bonus, I chose a light gray PLA-LW so the inside of the chamber should be brighter without adding more LEDs.
As another added bonus, I was planning on making the insulated top a 100 mm tall truncated pyramid with a filament feed hole on top, similar to the design of my 3D printed SV08 enclosure. I greatly prefer to mount the filament above the printer and feed the filament directly into the top of the extruder without a reverse Bowden tube. I print a lot of TPU and it’s sensitive to PTFE tube friction. It’s also difficult to feed stiff and brittle filament such as Siraya Tech ABS-CF without it breaking in the PTFE tube, and it’s much easier to swap filaments without needing to remove and reinstall the PTFE tube each time.
I had thought of doing an extended top as well to make a better path for the PTFE tube, on my to do list, bonus is that it will print in one piece on my SV08!
Extra lighting is never a bad thing though, I designed this to add some 24V COB strip and it makes a really nice difference still hard to see under the nozzle, would need something mounted much lower to improve that but still an improvement.
I’m planning on an SV08 (or similar) version of the Zero thermal insulation tiles and top hat that prints in one piece per side on a larger printer, as well as the same parts broken into smaller pieces that can be printed on the Zero, with the hat connected into a single piece using 4 mm square pegs. That’s what I did with the sides and truncated pyramid top on my 3D printed SV08 enclosure that prints on the SV08.
I’m using the macro below to implement M191 and M141. On an unmodified Zero i get my chamber from 22°C room temperature to 40°C in 10-15 minutes with just 100° bed heating.
[gcode_macro M141]
gcode:
SET_TEMPERATURE_FAN_TARGET temperature_fan=exhaust_fan
target={params.S|default(0)}
[gcode_macro M191]
gcode:
{% set s = params.S|float %}
{% if s == 0 %}
# If target temperature is 0, do nothing
M117 Chamber heating cancelled
{% else %}
SET_TEMPERATURE_FAN_TARGET temperature_fan=exhaust_fan target={s+2}
G28
G0 X75 Y75 Z5 F1500
SET_FAN_SPEED FAN=fan0 SPEED=0.5
{% if not printer["temperature_fan exhaust_fan"].temperature >= s
%}
SET_FAN_SPEED FAN=fan2 SPEED=0
SET_FAN_SPEED FAN=fan3 SPEED=0
M140 S100
{% else %}
M140 S0
SET_FAN_SPEED FAN=fan2 SPEED=0.5
SET_FAN_SPEED FAN=fan3 SPEED=0.5
{% endif %}
M117 waiting for Chamber temperature
TEMPERATURE_WAIT SENSOR="temperature_fan exhaust_fan"
MINIMUM={s-1} MAXIMUM={s+10}
SET_TEMPERATURE_FAN_TARGET temperature_fan=exhaust_fan target=0
M117 Chamber at target temperature
{% endif %}
Been working on this for a little while, made some final tweaks today and reprinted a couple of times but its looking good so far, has a 24V 4020 fan and a 12v 50W PTC heater, I’ve found a 24V 100W PTC heater that appears to be about the same size so I’ll order that in the next couple of days as 50W is pretty limited in heating capability.
Fits on a side panel and just uses magnets to keep it in place and clears the print bed with a handful of mm to spare!
Be careful adding 24V loads to the Zero power supply, it hasn’t much spare capacity.
I had the idea to get a small heat gun and a solid state relay. Gut the heat gun, attach the heater to the SSR and Cut the housing in half and make an adapter for a 24Vdc fan. Hook the other side of the SSR to the chamber heat pin on the MCU and make a thermostatically controlled chamber heater.
If you want tap it in at the INPUT to the power supply or just plug it into the mains.
That Zero chamber heater is very nice! I’m a bit sketchy on making things designed to get hot, particularly in plastic enclosures, but this is very well implemented. I assume it’s a chamber pre-heater that would only be used when you’re there watching it, and PTC offers a lot of safety. I’d either power it remotely or upgrade the Zero power supply and power it directly from the upgraded power supply, via a fuse and switch.
Yeah, they self regulate so shouldn’t thermally run away and should shut off if the fan fails so I feel ok with them, I can make them shut off by increasing the voltage, 14V draws around 100W from this PTC and it shuts itself off after about 30-60 seconds.
Most PTC modules come mounted in ABS plastic brackets, and this black one was printed in ASA, haven’t seen any warpage yet, my earlier prototype was printed in PLA and didn’t fair so well but still remained in tact…
I plan on controlling it, just don’t see a real need to keep it operational after printing temp is reached as the heat from everything else inside the chamber will increase the internal temp more anyway, I can only get to the high 30’s with this 50W unit, while printing the Zero will get into the mid 50’s.
The tiles wouldn’t interfere with the Zero’s range of motion or operation, other than making passive heating more effective. For me, that would only mean that the exhaust fan would turn on sooner when the chamber reached 60 C… or 50 C for PETG. The Zero would be more energy efficient, it would dump less heat into my office, and it would be quieter. It would make PLA cooling slightly more problematic but I don’t print high speed PLA. As an added bonus, I chose a light gray PLA-LW so the inside of the chamber should be brighter without adding more LEDs.
