Enclosure and ASA, temp at 50C+
Hello!
While printing ASA for several hours, I've observed that the temperature inside the enclosure reaches around 50C. This has raised some concerns for me, particularly regarding the printer itself and the quality of the printed parts, specifically for my MK4.
Are there any potential issues or risks I should be aware of when printing with ASA at such elevated temperatures? Have you encountered any challenges or observed any adverse effects on the printer or the printed parts when operating at around 50C?
To proactively address this situation, I'm considering purchasing a fan and creating a ventilation hole at the top of the enclosure. My goal is to effectively expel some of the hot air when the temperature exceeds 50C, potentially safeguarding both the printer.
Thank you for taking the time to assist, and I'm eagerly looking forward to your response.
Best regards
RE: Enclosure and ASA, temp at 50C+
Have a look on my thread for this. I encountered several printer crashes when the temperature inside the enclosure went too high. I am currently testing a modified cover for the electronics box that has an 80 mm Noctua embedded. When I print PLA with the enclosure doors open and the fan off I can see a board temp of over 60 °C in the sensor values on the printer display. The fan brings that down to about 45 °C. Ambient temperature here is at about 26 °C currently. I also want to insulate the board from the metal back of the electronics case because I think that the heat pads between the xBuddy board and the back of the case work the wrong way around and actually cause the board getting too hot when the heat bed is at temperatures for PETG or even ASA/ABS. I will do the insulating some time this week.
RE: Enclosure and ASA, temp at 50C+
Thank you!
I will be adding a fan to the enclosure that will effectively expel the hot air when the temperature exceeds the threshold of X degrees. This proactive measure should help maintain a more controlled environment during the printing process. Thank you once again for your helpful advice!
RE: Enclosure and ASA, temp at 50C+
I added a 120mm exhaust fan to the "cutout" on the rear of the enclosure.
I also use Octoprint, so I added a temperature sensor to the enclosure, and a relay and PWM control for the fan via the Raspberry Pi. I wrote some scripts that accept a "threshold" temperature and turns on the exhaust fan when above that temperature (and increases PWM as needed). I then added a small script to Octoprint which extracts the filament type embedded in the file name by PrusaSlicer, and automatically calls the bash script with the proper threshold temperature for that filament type. It is all pretty automatic now: I just slice the file and send to Octoprint, which detects the filament type and and calls the script with the appropriate temperature threshold, and the script regulates the fan (as needed) to keep the temperature below that threshold. A final "after print completes" script in Octoprint sets the fan to 100% to cool down the enclosure.
It all works pretty well during printing, as not much replacement air is needed to regulate the temperature and the fan doesn't need to do very much. The cooldown phase (where fan goes to 100%) doesn't work as well as it could, because there isn't enough "leakage" to keep up -- it actually creates a slight vacuum in the enclosure so the fan can't reach full speed unless a door is opened. I had thought the leakage from all those extra 3mm holes and cable pass-through cutouts would provide enough venting to keep up with the 120mm fan, but it doesn't.
RE: Enclosure and ASA, temp at 50C+
I've never had an electronics issue with temp I get when printing ASA or PC-CF but I have had the PINDA holder on my Mk3S melt and bend so I reprinted it in PC-CF.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Enclosure and ASA, temp at 50C+
Have you had any issues with hardware?
RE: Enclosure and ASA, temp at 50C+
No, no issues. Full disclosure, I do NOT have a Prusa enclosure, just LACKs for all my printers but the XL, so YMMV.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE:
I have not had any issues with the electronics, but I don't think the enclosure has been over 45C (I have the Prusa enclosure). Have not printed any PC or ASA on the MK4, but a fair amount of ABS. It is pretty rare for the room temp to get over 21C where I live, so there is a lot of cooling power with just a little replacement air coming into the enclosure.
I assumed (right or wrong) that Prusa tested and knew what they were doing when leaving the electronics inside, i.e., that the temps reached via passive cooling aren't going to be an issue for most people. My main reason for the exhaust fan was to keep a reasonably low temperature when printing PLA/PETG without having to open the doors.
RE: Enclosure and ASA, temp at 50C+
As soon as the heated bed reaches 90 °C there is no more passive cooling for the board, more like active heating in the opposite direction via thermal radiation of the heated bed to the back of the electronics case and then the heat pads between the back wall of the case and the board. You can observe the rise of the temperature in the sensor display for the board temperature. Info > Sensor Info > Board Temperature. No "cooling" there.
RE: Enclosure and ASA, temp at 50C+
So I've noticed that the temperature inside the Enclosure goes up to 40 degrees and beyond very quickly. In the warranty of the Mk3s+ and the Mk4, a maximum ambient temperature of 38 degrees is specified. Anything above that is no longer covered by warranty and you will not get a replacement from Prusa and will be out of luck.
Unfortunately, I find all this very contradictory and therefore the enclosure for the Mk3s+ and Mk4 completely unsuitable. Even if I open the ceiling at 40 degrees, the temperature inside needs about 1 hour to drop about half a degree. PLA and PETG printing is not possible with a closed enclosure because the temperature there is also much too high too quickly.
RE: Enclosure and ASA, temp at 50C+
Sorry, I meant to say passive heating, not cooling; i.e., I was referring to the enclosure being passively heated by the printer (mostly the bed) as opposed to someone adding an additional heat source like a space heater to deliberately achieve higher temperature.
For full context, my assumption was/is that Prusa engineers decided the temps reached inside the enclosure during printing would typically not exceed the design limit for the electronics.
Of course, the engineers could be wrong. Or there could be a few boards that don't handle the rated heat specification. Or someone may be printing in Death Valley with 54C ambient, which probably wasn't considered "typical" by the engineering use case.
It is early yet, but so far I haven't seen a bunch of reports about MK4's overheating. Time will tell I guess.
As soon as the heated bed reaches 90 °C there is no more passive cooling for the board, more like active heating in the opposite direction via thermal radiation of the heated bed to the back of the electronics case and then the heat pads between the back wall of the case and the board. You can observe the rise of the temperature in the sensor display for the board temperature. Info > Sensor Info > Board Temperature. No "cooling" there.
RE: Enclosure and ASA, temp at 50C+
I think the engineers have not thought about this at all.
Sorry, I meant to say passive heating, not cooling; i.e., I was referring to the enclosure being passively heated by the printer (mostly the bed) as opposed to someone adding an additional heat source like a space heater to deliberately achieve higher temperature.
For full context, my assumption was/is that Prusa engineers decided the temps reached inside the enclosure during printing would typically not exceed the design limit for the electronics.
Of course, the engineers could be wrong. Or there could be a few boards that don't handle the rated heat specification. Or someone may be printing in Death Valley with 54C ambient, which probably wasn't considered "typical" by the engineering use case.
It is early yet, but so far I haven't seen a bunch of reports about MK4's overheating. Time will tell I guess.
As soon as the heated bed reaches 90 °C there is no more passive cooling for the board, more like active heating in the opposite direction via thermal radiation of the heated bed to the back of the electronics case and then the heat pads between the back wall of the case and the board. You can observe the rise of the temperature in the sensor display for the board temperature. Info > Sensor Info > Board Temperature. No "cooling" there.
RE: Enclosure and ASA, temp at 50C+
No Death Valley here, but 2 weeks ago I had over 40 °C ambient here. That was apparently too much. Now after several rainy days the ambient during the day is down to about 25 °C.
RE: Enclosure and ASA, temp at 50C+
I am printing ASA right now, have a case temp of 35.7 degrees and a board temp of 65.7 degrees at 100 degree heat bed temp.
As soon as the heated bed reaches 90 °C there is no more passive cooling for the board, more like active heating in the opposite direction via thermal radiation of the heated bed to the back of the electronics case and then the heat pads between the back wall of the case and the board. You can observe the rise of the temperature in the sensor display for the board temperature. Info > Sensor Info > Board Temperature. No "cooling" there.
RE: Enclosure and ASA, temp at 50C+
Even the support advises to open the lid (mod) of the enclosure at temperatures above 38 degrees to dissipate the heat. This should not affect the quality of the print at ASA (warping). But why do I buy an enclosure if I am not allowed to print anything closed?Here definitely must be improved and a reasonable temperature management on the part of Prusa must come. I'm still waiting for the planned Smartbox. Maybe we'll get something in 10 - 20 years. Irony off...
RE: Enclosure and ASA, temp at 50C+
That is exactly the same thing that I observed. Putting a fan on the electronics box can help a bit there. I am testing an 80 mm Noctua on the cover of the box. This seems to work during my first tests. Since I put the fan there I had no more red screens. But I have not yet run any longer tests with higher temp filaments and a closed enclosure. My next step will be to remove the heat pads behind the board and put a sheet of cork there to see how much that will improve. I also want to put some small raspberry pi heatsinks on the chips on the board to help with convection together with the fan. I have not looked closely enough to see how feasible this is, because I can not look inside there when the printer is inside the enclosure.
I am printing ASA right now, have a case temp of 35.7 degrees and a board temp of 65.7 degrees at 100 degree heat bed temp.
As soon as the heated bed reaches 90 °C there is no more passive cooling for the board, more like active heating in the opposite direction via thermal radiation of the heated bed to the back of the electronics case and then the heat pads between the back wall of the case and the board. You can observe the rise of the temperature in the sensor display for the board temperature. Info > Sensor Info > Board Temperature. No "cooling" there.
RE: Enclosure and ASA, temp at 50C+
I plan to add a microcontroller with temp sensor and fan to regulate the maximum enclosure temp. When I do, I will post how I did that, including any code I write. But just like Prusa, don’t hold your breathe waiting for the release. 🤣
RE: Enclosure and ASA, temp at 50C+
A friend of mine has already tried exactly that with 120mm fan. The result: it doesn't work, because the warm air is not removed quickly or well enough.In addition, you create only a negative pressure in the case. You need 2 fans, one that blows cold air into the case and one that blows warm air out the top.
RE: Enclosure and ASA, temp at 50C+
A friend of mine has already tried exactly that with 120mm fan. The result: it doesn't work, because the warm air is not removed quickly or well enough.In addition, you create only a negative pressure in the case. You need 2 fans, one that blows cold air into the case and one that blows warm air out the top.
It works pretty well for me. But there are some caveats.
The fan DOES exhaust hot air, even with doors and lid closed. The Prusa enclosure is far from airtight. There are lots of holes and gaps, and external air infiltrates through those to replace air being exhausted by the fan.
The type of fan used matters a lot. I used a high static pressure (2.83 mm H20), 1700rpm max, 120.2 m3/h (70.75cfm) 120mm pwm fan. Even with the high SP design, the fan is unable to move its "full rated volume" when the doors and lid are closed because there is insufficient intake venting. But there is enough infiltration through the holes and gaps for the fan to move between 1/3 to 1/2 of its rated volume (i.e., approximately 24 to 35 cfm).
The interior air volume of the enclosure with the printer inside is less than 6 cubic feet, so even at 24 cfm the entire volume can effectively be replaced with external air about every 15 seconds. That could be increased with additional venting, but I have not found that to be necessary in my environment.
I have had no trouble keeping the internal temperature stable during long prints with this setup. But I am printing ABS, so bed temp is 110C (vs the 115C for PC), and my room air is a nice, cool 20-21C. Under these conditions, I have been able to maintain <38C indefinitely, and never using more than 70% pwm on the fan. Would it work with PC and the extra 5C bed temp? Probably, since it only needed 70% pwm with ABS, but I have not tested with PC. And it certainly will not work well if the room air being taken in is already hot.
RE: Enclosure and ASA, temp at 50C+
That sounds good to me. Have you ever thought about a second fan that brings air into the case from the outside? That's what you do with a PC case. Maybe you can increase the volume that way?
A friend of mine has already tried exactly that with 120mm fan. The result: it doesn't work, because the warm air is not removed quickly or well enough.In addition, you create only a negative pressure in the case. You need 2 fans, one that blows cold air into the case and one that blows warm air out the top.
It works pretty well for me. But there are some caveats.
The fan DOES exhaust hot air, even with doors and lid closed. The Prusa enclosure is far from airtight. There are lots of holes and gaps, and external air infiltrates through those to replace air being exhausted by the fan.
The type of fan used matters a lot. I used a high static pressure (2.83 mm H20), 1700rpm max, 120.2 m3/h (70.75cfm) 120mm pwm fan. Even with the high SP design, the fan is unable to move its "full rated volume" when the doors and lid are closed because there is insufficient intake venting. But there is enough infiltration through the holes and gaps for the fan to move between 1/3 to 1/2 of its rated volume (i.e., approximately 24 to 35 cfm).
The interior air volume of the enclosure with the printer inside is less than 6 cubic feet, so even at 24 cfm the entire volume can effectively be replaced with external air about every 15 seconds. That could be increased with additional venting, but I have not found that to be necessary in my environment.
I have had no trouble keeping the internal temperature stable during long prints with this setup. But I am printing ABS, so bed temp is 110C (vs the 115C for PC), and my room air is a nice, cool 20-21C. Under these conditions, I have been able to maintain <38C indefinitely, and never using more than 70% pwm on the fan. Would it work with PC and the extra 5C bed temp? Probably, since it only needed 70% pwm with ABS, but I have not tested with PC. And it certainly will not work well if the room air being taken in is already hot.