Neptune 2S Dual Fan Shroud Upgrade

Dual Fan Shroud Upgrade for my Elegoo Neptune 2S

(with RGB for flavor)

Dual Fan 3D Printer Header

One of the biggest downsides of the Elegoo Neptune 2S is the single cooling fan on the hot end. The Neptune 2 (and 2S) have a singe fan on the left side of the hot end, which works fine for some normal printing, but not for all. If you start to print objects with overhangs, you will quickly understand why upgrading your beloved 3D printer with a dual fan shroud setup is essential.

The fan on the front of the hot end is to help cool the heatsink mounted to the heat break, and the fan on the side is to assist cooling the material (PLA, TPU, ABS, ETC) before it attempts to sag. The common problem with the Neptune 2 (and many other FDM printers with single cooling fans) is that you will get adequate cooling on one side, but not enough on the right side of your prints. This is where the dual fan (or dual blower) upgrade is handy.

My Choice in Design:

First off, I wanted to upgrade, but I also wanted to have a dual fan setup that fit two criteria. 1. I wanted things to be as easily serviceable as possible. 2. I wanted the final look to be as close to a stock look as possible.

Easily Serviceable meant I didn’t want to have to resplice wires every time I needed to replace a fan. As anyone in IT or repair industries know, if it has moving parts, it will fail. For this, I opted to splice my wires and add connectors to them so I can swap out and replace fans with relative ease. I also wanted fans with connectors on them so I could unplug as needed.

For the fan shroud I wanted something that added the second fan (or duct from a single fan to air flow on both sides of the hot end), but kept everything as clean as possible. This was not easy as most fan designs were bold, or huge, or used large blower fans. These looked nice and looked like the worked well, but not what I was looking for. After some time of searching, I found a great design on Thingiverse. The “Elegoo Neptune 2 Fan Mount for 2 part cooling fans” which not only looked great, but name just rolls of the tongue.

Fan Shroud:

I wound up printing 3 of these shrouds. The first one had an “accident” during the clean up. I was trying to use up some black filament I purchased that strings… A LOT. This required a fair amount of clean up to remove the “wookie” effect the firmament left behind. Unfortunately during the clean up for the first print, one of the internal fan holding pieces broke and gluing was not an option. I was a bit more careful during print 2 and 3.

Elegoo Neptune 2 Fan Mount for 2 part cooling fans

Elegoo Neptune 2 Fan Mount from Thingaverse

These fans shrouds are only slightly wider than the stock single fan shroud, but does add some length from the heat sink to accommodate deeper fans like the Noctura if you wanted to go that route. I chose to stick with 24V fans instead of the 12V Noctura fan and a voltage converter. I didn’t want to add another point of failure to my 3D printer with the voltage converter. So I went with dual 4010 WINSINN blower fans, and the Makerhawk 40mm 24v RGB fan. I also ordered a kit of connectors so I can easily replace fans in the future without have to solder and splice again.

Test Fitment:

Before you start hacking and cutting your Neptune 2S, it is always best to test fit the fans in your new fan shroud to make sure everything fits, and to see how you want to lay out wires. I found that I had to break the tab on one of the blower fans as the cable came out the side, and was hitting on the shroud preventing the fan from seating all the way.

Dual Fan Shroud Test Fit Dual Fan Shroud Test Fit

One of the other common issues with the stock Neptune 2 and 2S fans is that they can be a bit noisy. Not uncommon for the fans to have a rattle sound to them. I decided to tackle this with some double sided heavy duty tape. Not only will the double sided adhesive help hold the fan in (not to rely on screws) but the thick rubber will reduce vibration noise. Just a word of caution, try to keep the tape away from the inner edge where the fan spins. The impeller will move outward a little bit and if there is a small bit of tape sticking out, the fan blade will get stuck on it.

Heavy Duty Tape fan mounting Heavy Duty Tape fan mounting

If you get some excess sticky tape that is protruding into the fan blades, a sharp knife may or may not work. I found it is best to take the fan back out, and move the tape slightly outwards. This way when it is “oozed” by the tightening of the screws, it still won’t protrude into the fan blades.

Wire splicing time

I wanted to keep the wires and connectors as hidden as much as possible (within reason). As well as not having to cut the wires of the fans making them easily replaceable. My plan was keeping the connectors and splicing all within the cable mesh wrap as much as possible. I color coded with heat shrink on which one was for the hot end, and connectors for the part cooling.

Soldering on the connector Dual connectors for dual blower fans

The wire kit came with both connectors with wires, and the connectors themselves. For the single fan that cools the heat sink, I cut the wires and soldered a connector directly to it. For the dual blower fans, I cut the wires further back and used two of the premade connectors with wires to solder on a ‘Y”. Now all 3 fans can be easily replaced in the case of failure.

When wiring up the fans, the RED and BLACK wires on the heatsink fan are straight forward. For the blower fans, wire them YELLOW (positive) to RED, and BLUE (negative) to BLACK.

Finishing it all up

Overall I am very happy with the finished product. For my second Neptune 2S I plan on staggering the connectors, and cleaning up the cabling a bit more. That being said I am very happy on how it all turned out. The cabling mesh is a bit of a trick to get over the bulk of the cables, but looks decent when when it is done. In all I am loving the dual fan shroud upgrade.

Dual Fan Upgrade with RGB Goodness Dual Fan Upgrade Complete

Here is a video I posted on Tiktok showing the upgrade:

@audiocraz Dual fan setup on Printer B.#3dprinting #3dprintingtiktok #3dprint #rgb ♬ original sound – AudioCraZ



Elegoo Neptune 2 Fan Mount for 2 part cooling fans – Thingaverse




Links to Amazon are Associate links. If you wish to purchase any of the items listed above, I would greatly appreciate using the links provided above. You can also support my content by subscribing on Patreon. They help me to provide more content and reviews. As always, happy printing and thank you! – AudioCraZ

Updated: March 4, 2022 — 6:25 pm


Add a Comment
  1. How’s it going guys. Great post and super helpful. The one thing for me though is when both part fans are connected my print will stop and give ERROR 7. Which I’ve concluded to be a power issue. I have my fans spliced exactly like yours. When I disconnect one fan, machine runs perfect. They are 5150s. Does that make a difference? TIA and keep up the great work!

    1. The 5150 fans pull a considerable more power than the smaller 4010 blower fans. As such, you can not run those fans in dual at 100%.

      In your slicing software, turn your fan speed down to 50%, re-slice, and see if that helps.

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