Loud Fans

[Tim]

Having full 24 volts across the extruder fan means I can put 24V of LEDs (two 12V strips in series) in parallel with the fan.

You should see my setup. . . By carefully counting my LEDs, I got a string running around the inside of the frame sides and top, and an additional set of three under the fan, wired back into the electronics case using a spare wire pair that was left over from the dual extruder harness. Wiring LED strips in series is tricky; you have to have exactly the same number of lights in each set (I'm sure you know that, Dale; just a warning to anybody who wants to try it for themselves). Although LED manufacturing is quite precise, so the voltage drops should be almost exactly equal. The 12V fans in series is another story (as I mentioned in another post a few minutes ago). I should go press my finger on one of them and measure how the voltage across it changes as it slows down. My extruder fan makes a lot of noise when it starts up. It could just be the bearings, but I think it may be due to oscillations in the load conditions as it powers up. After 5 to 10 seconds, it stops all the noise and quiets down and stays that way until the next time I power up. I replaced one fan that was doing that, but the replacement fan started to do it, too, after a few weeks. Which is why I think it may not have anything to do with bearings.

[Kulturfolger]

Hello,

I am the new guy. I bought a used makergear m2 (24v v3b) from an auction. The prior owner had to shut down its business due to an insolvency. The fans are my main concern with this rather new machine. I could measure 65 dB of noise while sitting idle. I want to make this machine as silent as my mendel90 which has a single 120mm fan within the power supply rated at the same power and a single 50mm fan for cooling when printing with PLA.

Generic idea:

Its a really bad design to wire two 12V fans in series to 24V. The voltage is not evently distributed. While the fan in the box might have a lower resistance as this on needs more current to push the air out. So the cooling fan near the printhead gets more power. The fan whose bearings get bad first will kill the other fan. Why build 24V fans by default or include a small dc/dc converter for the fans?


My idea for the power supply:

[*]The power supply has a heat issue, the plastic case forces the air to recirulate inside of the enclosure. My first fix is to alter the airflow by putting a stripe of self ahesive foam next to the fan so it sucks in fresh air in from the outside and the warm air is forced out of the plastic box. It might need a few additional holes to the original case but this should lower the temperature drastically. The fan build into my supply is a 12V SUNON KD1206PTB1 with 34.5 db and an airflow of 0.665m³/min. I will replace it with a Noctua NF-A6x25 FLX 60mm which has an airflow of 0,49m³/min and noise as low as 19.3 dB

The rambo box is extremly loud:

[*] The rambo box has a tiny 40mm fan in the upper left spot but most heat is generated by the stepper drivers on the right. The could air should be forced to flow around them first. The air the fan sucks in exists through the holes on the left and the space around the power connector. No head is removed from the stepper drivers. A baffle closing the holes next to the fan would force the air to exit near the stepper drivers, but the noise would be the same. I guess I will move the electronics way to the side of the gantry. With head spreaders glued to the stepper drivers and the headbed power switched by an external device the temperatures should drop to a point where no forced ventilation is needed. On the other hand the additional headroom gives me the room the install a bigger fan. Without any fan grill (even the rambo box has this design) the noise due to the turbulences created should drop significantly.

Fans at printhead:

[*]The fan cooling the direct drive would work with a 50mm fan as well. This fan without a fan grill will be completely silent. Same with the fan cooling the freshly printed plastic. On the long run I will replace the printhead/hotend with a E3D one, there is no more issue with heat traveling upwards.

Greetings,
Ingo

[Jules]

Hello,

I am the new guy. I bought a used makergear m2 (24v v3b) from an auction. .......Ingo

Welcome to the group Ingo.

[Kulturfolger]

Hey Jules!

I replaced the fan within the PSU to the Noctua NF-A6x25 FLX 60mm 24V FAN. The noiselevel is acceptable while sitting on the table.
An online housing construction service is currently building an aluminium case with a perforated plate in the front and a place for two Noctua 60mm fans running in the back. The PSU will sit inside with another 12V (2A) Supply. The 24V Connection will be made with Neutrik with a powerCON 20A and an locking xlr provides 12V.

The rambo box will be a Lulzbot RAMBo Electronics Enclosure featuring a 80mm fan. The case is all metal so all connector can be mounted really nead. I need space for the SSR and a few other things.

Did anyone apply water cooling to the steppers?

Ingo

[insta]

There is zero need to watercool the steppers, there is actually an anti-need to do so.

[Matt_Sharkey]

I thought about liquid cooling the steppers if I went for a heated enclosure with ABS.

Then I woke up and bought PETG.

[innkeeper]

when i upgraded my m2 to using a smoothie board, i moved the case so it was sticking out the front far enough to place the fan on side so it was getting fresh air from the side of the printer, not pulling hot air from inside the printer generated by headed bed and z stepper.... also seems to be rather quiet.. maybe because of the new case begin printed... not sure

i've seriously considered just drilling a hole in the top of the ps case, and putting in a foam spacer and a grill to the ps gets direct outside air, i'm glad i am not the only one bothered by that design that recalculates the hot air

i like the idea of using Nocturnal fans.

what i have done to reduce vibrations on the extruder fans is to used a washer between the fan guard and the fan, and make sure all 4 corners of the fans have bolts,
not a cure all it helped for me. That was not my idea, i read that someplace else a long time back, like 2013.

[Kulturfolger]

There is zero need to watercool the steppers, there is actually an anti-need to do so.

Well, if you print PLA, everything might be fine. But if you try printing fast, reliable with more challenging materials the hot drivegear will drive you crazy as the filament will get to soft where it should be stiff. Print smaller objects or things with many retracts and things get worse. The fan blowing against the drivegear creates to much cooling when you dont want cooling of the printed stuff at all.

My target specs are: Heated build chamber up to 70°C and Heated print bed (up to 130°C). Everything in an airtight box with activated carbone fume absorbtion. My extruders I currently use are able to withstand 300°C.

In this enviroment a water cooling is the only choice keep the steppers and termal brake cool.

i've seriously considered just drilling a hole in the top of the ps case, and putting in a foam spacer and a grill to the ps gets direct outside air, i'm glad i am not the only one bothered by that design that recalculates the hot air

You might just switch to these endcaps, the PSU will suck in cold air: http://www.thingiverse.com/thing:753888

what i have done to reduce vibrations on the extruder fans is to used a washer between the fan guard and the fan, and make sure all 4 corners of the fans have bolts,
not a cure all it helped for me. That was not my idea, i read that someplace else a long time back, like 2013.

Just remove the guards, they are only for the show I guess. They serve no other purpose. 24V 50mm fans are quiet and the upper fan would work even better with a small box directing all the air upwards.

Ingo

[innkeeper]

You might just switch to these endcaps, the PSU will suck in cold air: http://www.thingiverse.com/thing:753888

brilliant i love it, I never seen that before. I am so doing that!

[jimc]

boy those end caps are super nice. great idea..