Question A few questions about fans while assembling my Trident

[jesjimher]

Printer Model

Voron Trident 300 (Formbot)

Hi!

I've just started assembling my brand new Voron Trident Formbot kit (300 size), and I have some questions.

I'm a little bit worried about noise. I've heard that Formbot fans aren't that good, and are on the noisier side. I've seen a popular choice is replacing electronic bay fans with Noctuas. But stock fans are 60x60x20, while Noctua fans (NF-A6x25) are 60x60x25. Will those extra 5mm be a problem? Do I need to print a modified part, or stock part is good enough? I bought all parts from PIF and I don't have access to a 3D printer right now (I'm building one ).

For the rest of the fans, a while ago I saved a reddit post that mentioned different brands and models. But since all the Reddit conflict, Voron subreddit went private, I can't see those posts anymore, and for the life of me can't find the information about proper replacements for hotend fans. Any advice about brands/models?

Thanks a lot!

 

[NoGuru]

Fans are pretty easy to swap out after they are installed. I would say build with what you have and then if you want to swap out later its pretty easy.

 

[claudermilk]

I swapped to those exact Noctua fans, they fit fine and I just had to swap to longer screws to fit. It's one of my favorite upgrades--quiets the printer a ton. The toolhead fans are Delta & GDSTIME and aren't too bad. When printing ABS, the enclosure muffles it somewhat.

 

[Sanity Agathion]

60x25 Noctuas will work just fine. One more tip: print skirt fan mounts without those fan grills, just holes, and get bunch of metal fan grills or print some simple. Those covers cause a lot of noise for some reason.

Good brands for 4010 hotend fan are GDStime 2 ball bearing, NMB 04010SS-24N, Orion OD4010-24HB, E3D Hemera fan for example. Buy ball bearings rather than sleeve or even those fancy hydraulic bearings like on Sunons - sudden moves during front to back accelerations don't do those bearings any favor and fans may prematurely die.

 

[Sandman50]

I have a fysetc kit - likely similar fans. To control noise, I just dropped the speed down to 0.8 speed. No issues with electronics temperatures. I presume those fans will fail eventually though, so higher quality ones sooner or later.

For a stealth-burner hot end it can matter if you have a toolhead board that can handle a PWM fan like a BTT EBB2209. Regardless, you will want a hotend fan that is a 4010, ball bearing, and can push at least 6 CFM of volume to keep the hotend cool. As I have a EBB2209 board, I run a PWM fan from digikey.

The reason for a PWM fan is to get the speed feedback so you know if it's off and you can shut down the machine so it doesn't melt down the hotend. The extra fan output is used to cool the EBB2209 board with the stepper driver in it for the extruder.

 

[jonhi]

I swapped to those exact Noctua fans, they fit fine and I just had to swap to longer screws to fit. It's one of my favorite upgrades--quiets the printer a ton.

How would you connect the fans if I may ask? My fans seem to have a 2-pin connector (combined via a small PCB provided by LDO) that connects to the Octopus, but the Noctua fans either have a 3-pin or a 4-pin if you use the pwm variant.

And what about the voltage? On the LDO trident kit everything except the Pi seems to be 24V, I assume that's the same for the fans? But the Noctua fans seem rated for 12V?

 

[jesjimher]

And what about the voltage? On the LDO trident kit everything except the Pi seems to be 24V, I assume that's the same for the fans? But the Noctua fans seem rated for 12V?

If I remember well, Octopus board lets you choose the voltage for every fan connector, so that shouldn't be an issue.

 

[jesjimher]

How would you connect the fans if I may ask? My fans seem to have a 2-pin connector (combined via a small PCB provided by LDO) that connects to the Octopus, but the Noctua fans either have a 3-pin or a 4-pin if you use the pwm variant.

Just found a blog post about how to connect a Noctua 3-4 pin fan to an Octopus board. 3 pin, non-PWM Noctua fans seems pretty straightforward to connect, and 4 pin PWM require a bit more of tinkering:

Driving a 4-pin computer PWM fan on the BTT Octopus using Klipper – Nicholas Sherlock

My doubt is, is it really necessary having PWM in those fans? They're just for cooling electronics, perhaps fixed RPMs would be just fine.

 

[claudermilk]

I just ignored the third wire. I installed mine long before LDO came up with their PCBs, so I have a couple of Wago blocks to combine the wiring. On the Octopus, each fan header can have the voltage set, so I just changed the one the Noctuas plug into to 12V (I forgot initially and wondered why they were running so hard for a few moments. Oops.)

 

[Molot]

My doubt is, is it really necessary having PWM in those fans? They're just for cooling electronics, perhaps fixed RPMs would be just fine.

With PWM, you can get to lower speed without stalling. That's pretty much everything that is to it. You can totally buy Noctua FLX series and not use PWM. On the other hand, afaik Noctua does not guarantee reliability if you try to slow down PWM fan using voltage, or FLX fan using PWM on power line.

 

[jesjimher]

With PWM, you can get to lower speed without stalling. That's pretty much everything that is to it. You can totally buy Noctua FLX series and not use PWM. On the other hand, afaik Noctua does not guarantee reliability if you try to slow down PWM fan using voltage, or FLX fan using PWM on power line.

Ok, I was thinking about using (Noctua provided) cable for reduced RPM/noise. Not sure electronics cooling actually requires dynamic adjusting of RPMs, perhaps setting Noctua fans at their lowest RPM setting is more than enough... Anyway, more control options have never hurt anybody

 

[claudermilk]

I don't bother on my Noctuas. They are either on or off. That extra wire just hangs to the side.

 

[majic79]

I don't mind the noise, it's not excessive, but I've set the fan output for the stock fans to 50% duty cycle and it brought the noise down to an acceptable level. My trident will be living in the garage anyway, so it's not going to keep me up at night