Ambient temperature vs mintemp
Hi guys,
I have a MK3 for almost 3 years and it's still working very good. Prints are pretty much what i expect from it every time.
But something is bothering me and i still can't understand exactly why this is a problem, probably for more users as well.
The printer is located in my garage/hobby room, and when it's cold outside the temperature drops a little below 10 degrees celsius.
Then i get the mintemp error, for bed and extruder. So i get the heat gun to bump it to 13-14degrees and the 'problem' is solved.
So their is no hardware error, just a low ambient temperature causing the mintemp issue.
Now i understand that bypassing temperature values isn't the way to go, but heating the sensors isn't either i guess.
Their must be a solution to this, like compare with ambient temp or heat for 5sec and detect rate of change or something? I know that ambient temperature can also be easily changed, but heating the whole place for my printer to start sounds a bit silly to me.
Is this a problem among all prusa type of printers, and do i just have to 'suck it up'? 😊
Nevertheless, i'm still very happy with my printer. 👍
Grtz Jeroen
RE: Ambient temperature vs mintemp
The mintemp is set for safety reasons. The way I read it is that the thermistors and board don't read reliable below a specific temperature.
Even Prusa says heating with a heat gun is a workaround for this.
https://www.help.prusa3d.com/en/article/mintemp-and-mintemp-bed_2169
RE: Ambient temperature vs mintemp
@Balkin has it spot on. It's a safety check. You don't want safety checks with complicated code and algorithms. If the temperature is below a range that the thermistor can detect while powering the heater cartridge, it stops.
Joan (@joantabb) described a delightful and very civilized solution someone in her group uses. Prior to the start of the first print of a day, the hotend is moved next to the bed and a hot cup of tea placed alongside it. After a leisurely cup of tea, printing can begin.
RE: Ambient temperature vs mintemp
Yes, i am aware that it's a safety check, and i'm glad this feature is included in this build.
However in my opinion this is a 'bug' in the safety check. It at least needs an option to start heating in cold environments.
The 'civilized' solution i would definitely NOT use, my printer is located in a closed box with my spools stored in it also. Placing a hot cup of tea in this box and letting al that moisture get into my printer and spools, no thank you. I also don't like tea. 🙂
Is there a way to adjust the values of the mintemp by my self, at own risk off course? 😊
Grtz
RE: Ambient temperature vs mintemp
My printer is in an enclosure in my basement work shop which can get down to 10 or 12 degrees C in February. I find that just turning the printer on and closing the enclosure door and vents gets the printer up to a working temperature in about 10 minutes. Probably on par with Joan's cup of tea minus the humidity.
This does seem like a bit of a bug but they are right up against the wall on code size. I personally would prefer other issues be tackled rather than waste cycles and space on this minor annoyance that only affects a few of us for brief portions of the year.