RE:
During one of the last Prusa Podcasts (aka PrusaLive) Jo answered a question about max temps for MK3xx and MK4 inside an enclosure. I tried to find the exact spot in the videos, but couldn't without watching whole episodes and that was too much for me. 🙂 Anyway he said 45 °C for the MK3xx and 43 °C for the MK4 but I think he was referring to the temp inside an enclosure, not to the sensor values from the motherboards of the printers.
Anyway my fan mod seems to be successful so far: I can print IS gcode files via OctoPrint, that was a bit of a hit and miss for my MK4 before. After about 8 multi-hour PLA prints (all IS, all via OctoPrint) since Sunday, no crash, no error screen and no failed print! PETG prints and higher enclosure temps will be next ...
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
Out of curiosity, I would like to see if JUST the heat sinks, with no fan, would be stable enough for you. I realize that the fan makes it better, so why disable it, but it would be an interesting data point.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I tested that. I switched the fan off and the xBuddy climbed from 50 °C to over 70 °C. And that is "just" for PLA ...
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I saw that, but you didn't let that continue until it "failed", which was my interest: do the heat sinks pull enough heat out of the board to prevent failure?
Again, I know it's kinda dumb, since the fan makes SUCH a difference, but I'm curious how close to the edge you were, since so many of us don't have that issue.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I have a big stack of failed prints already, no need to grow that further ... 🙂
For PLA it would probably be enough already, you are right. And it seems that my previous problems with printing IS gcode via OctoPrint had also more to to with board overheating than with "NIH syndrome", which is nice to know. 😉
And I want to go on testing with PETG/ASA/ABS/PC-Blend-CF etc. My MK3S+ can handle those just fine inside its enclosure with no fan on the motherboard.
And I'll have a nice project for the winter learning to integrate the PWM control of the Noctua, a one-wire Dallas temp sensor inside the xBuddy case and another fan for the back of the enclosure with an iris servo mechanism into OctoPrint. 🙂
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I have a big stack of failed prints already, no need to grow that further ... 🙂
Totally understand that one. Still kind of odd that you had the problem to start with, though.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
During the heatwave in June/July the room where the printers are, which is under the roof in my house, had about 45 °C ambient temperature with the printers off. I don't have AC. This could be a contributing factor.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
Considering that Prusa has said that the enclosure max temperature for the Mk4 should be no more than 43C... Yeah, I'd say that might cause a problem.
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>> What temp does prusa say is ok for the electronics? <<
The STM32F427xx processor continues to operate at temperatures from -40 to +105°C.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
The STM is not the problem here, more like the stepper drivers and the mosfet for the heated bed, because those chips have heat pads at the back of the board, the STM chip does not.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
From my point of view, 70 degrees is a bit warm for the power cables, and posibly the Connector for the power cabels.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
The STM32F427xx processor continues to operate at temperatures from -40 to +105°C.
For the TMC2130, the operational range is -40 to +125°C at which it continues to function.
The extra cooling you are doing now is unnecessary.
However, the extra cooling will increase the lifespan of the xBuddy board.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
If it keeps the printer from producing failed prints, I would not say it is unnecessary. 🙂
Just finished a 12 hour print job with IS printed via OctoPrint. Still no failed prints so far.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
The 43°C are certainly referring to the surrounding temperature. The board itself and the processor can certainly run a lot hotter without issues but they also will if the surrounding heats up.
Active cooling is an option if you keep having troubles. Relocating the electronics outside of the enclosure would be an alternative and that would also protect against a shortened board life span. You probably need to recrimp/extend some cables for that though.
Mk3s MMU2s, Voron 0.1, Voron 2.4
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
Yes, relocating the electronics to the back of the enclosure would be my fallback option. That is how Vorons and RatRigs do it. The fan is just less hassle for now. I have the tools for crimping and so on. I would leave the electronics case on the printer frame because it contributes to the stability same as the PSU replacement bracket on the other side. Also it serves as attachment point for the wire looms. I would just extend the cables from the case to the back either with recrimping or with Wagos.
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I'm thinking of tying this approach
https://www.printables.com/model/553004-prusa-mk4-board-cooling
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
I was thinking of something like this, now it is a no brainer 😀
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
Yes, this looks interesting!
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
Yes, relocating the electronics to the back of the enclosure would be my fallback option. That is how Vorons and RatRigs do it. The fan is just less hassle for now. I have the tools for crimping and so on. I would leave the electronics case on the printer frame because it contributes to the stability same as the PSU replacement bracket on the other side. Also it serves as attachment point for the wire looms. I would just extend the cables from the case to the back either with recrimping or with Wagos.
Yeah, I totally get that with the "less hassle" 😉
I really love Wagos. Especially how easy it is to change things with them. No recrimping of cables etc.
For my Mk3 and the Bror enclosure I relocated the PSU to the outside as that seems to be a rather picky piece of equipment when it comes to temperature but left the electronics where it was because I felt it was too much hassle to relocate it. For the PSU there are actually replacement pieces one can print to safeguard stability. Would be interesting to see if they updated it for the Mk4.
Mk3s MMU2s, Voron 0.1, Voron 2.4
RE: Possible overheating of the MK4 electronics case inside an enclosure with summer temperatures?
For the PSU there are actually replacement pieces one can print to safeguard stability. Would be interesting to see if they updated it for the Mk4.
No replacement necessary, the PSU replacement bracket included with the Prusa Enclosure fits on the MK4. Same for the attachment parts to fix the MK4 PSU to the back of the enclosure. The only difference on the MK4 PSU is the earthing wire and the power-fail connector, which are not relevant for this. The PSU Quick Connector is not exactly compatible to the MK4 but can be made to work, somebody on the forum has done that. Also an adapted version for the MK4 from Prusa should be available shortly.