Overheating Printer by Enclosing it?  

Re: Overheating Printer by Enclosing it?

For quieting the printer without an enclosure, see this thread:
http://shop.prusa3d.com/forum/improvements-f14/best-usd7-buck-improvement-you-can-make-t3051.html
The mass of the base gets rid of many resonances, which makes the printer pretty quiet, and higher print quality.

You could also put some sound baffles around the printer without a complete enclosure. A complete enclosure will trap heat (unless the enclosure has its own cooling fan to move air through it) which can be good for the print, especially for some filament types. Too much heat will, however, shorten the life of electronics and motors, and if the cold end of the extruder gets too warm it can mess up extrusion by softening the filament before it gets to the heat break, which makes it hard to push it through the nozzle.

So... it's a balancing act. Good luck. 🙂

Re: Overheating Printer by Enclosing it?

one of the main problems is that the coldend of the E3D v6 extruder needs to be cooled down to be "cold at touch". with the actual design of the printer and the extruder fan (the one at the left) this means: as soon as the temperature gets above 40 - 45°C you risk a clogging of the heatbreak when retracting.
while 45°C won't do any harm to the electronics or the steppers.

Re: Overheating Printer by Enclosing it?

I've built a 24 X 24 X 26 enclosure for my MK2S a few weeks ago to minimize sound since it's sitting in the middle of our office. I've done multiple long prints and have noticed that the temperature inside the enclosure only gets to about 30.5 degrees Celsius max. When the print is done and the sides are open you can definitely feel the heat inside. I have not noticed any issues printing PLA or PETG. I have plans to install baffles to the top of the enclosure to vent out some air but still keep it quiet but since the temperature has been holding consistently I don't I will need to.

Re: Overheating Printer by Enclosing it?

I have completely closed enclosure with no designated holes for venting. Power supply and raspberry pi sit outside.

Maximum temperature inside was 32 °C when printing ABS in summer. -> No heat problem

Re: Overheating Printer by Enclosing it?

I have an actively heated enclosure, although I've found the active heating is only really needed with ABS. All but the power supply is inside. Max temperature I've heated it to is 45C.

The printer is not likely to be your limiting factor here. I've found that filaments with a glass transition temperature too near the enclosure temperature (such as Nylon or PLA) tend to kink after retraction if the speed is too high. I solved it by printing them slowly and limiting retraction speed/distance. I've also added a higher flow hotend cooling fan to hopefully lower the heatbreak temperature, but haven't tested whether or not it's effective yet.

Re: Overheating Printer by Enclosing it?

I have a simple enclosure made from a discarded shower curtain that retains roughly 15°C above ambient. The power supply is uncomfortably hot during operation along with the more active steppers. I've since installed passive heatsyncs in the motors and a fan in the power supply and noticed the modified components to be roughly 5°C lower than prior, negligible increase in chamber temp. Beyond heroic measures i.e. liquid cooling blocks or Peltier pads, it is hoped that this effort is enough to bring printer within expected service life without introducing unwanted air flow or elaborate thermal management of chamber. Perhaps this is a solution that is enough for consumer grade performance needs?

-edit
Jason from Ultimachine has some knowledge to drop.

The main constraint is the a4982 stepper drivers which lists the upper limit operating range as 85°C. They have a thermal shutdown of 165°C and will generally cause skipped steps on prints if this happens.
There is no ambient temp feedback on the board and it is not capable of shutting down.
It is definitely possible for a printer to melt itself. There is thermal runaway protection in the firmware that disables the heater outputs.

Re: Overheating Printer by Enclosing it?

Some more data to share here...

I had a ~6 hour print run this weekend and measured the case temperature of each stepper towards the end of the print. Enclosure was at 43C and all the steppers were 60-65C, so ~20C above ambient. Most steppers can handle up to 100C case temp, so still plenty of margin.

Re: Overheating Printer by Enclosing it?

I wouldn't go past 50°C for enclosure though, steppers can go 100°C for short bursts like an hour but past 80°C, their expected service life drops off "exponentially". So, as usual "can", and "should" must be considered. 50°C recommended enclosure max is 80°C - 20°C (load delta) -10°C (crap happens delta) as far as stepper health is concerned. Again "can", "should", different...don't bork this up. My quote key is exhausted!

As for RAMBo scream, yeah, I've heard it. Thermistor frayed off during a corner print (move prints regularly to preserve/extend PEI life), temps went crazy and luckily an intermittent sensing caught heat past 310°C and shut the print down (PR firmware safety logic not Mini-RAMBo in-hardware feature). The thing wailed like a child stubbed his toe at 3AM. Checked my fire extinguisher expire date and moved my gallon of Acetone from under the printer enclosure after that wake-up call, could have been a lot worse than 25g of $50 filament wasted.