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BoM:

8 - M3 Screws ≤ 6.5mm

2 - 80MM fans, 12VDC

1 - 1.25mm 2 Pin Micro Male Connector

Ability to solder, or connect wires securely

Look at this for original BoM/if you have only 1 fan:

https://www.printables.com/model/669507-80mm-pc-fan-mod-for-ender-3-v3-se

Instructions:

(Be sure to save all screws you unscrew, most of them will be reused)

When this file is done printing, screw out the 3, 2mm hex screws that attach the extruder shell and disconnect the fan.

Unscrew and unplug the CR-Touch module from the tool head.

Once the shell and CR-Touch is off, screw the CR-Touch Module into the print as pictured with the original screws.

You can do the next 2 steps in an order you prefer.

cut off a good length of all the fan wires, and using the connector solder them together in series. NOTICE: The ender 3 pinout for the connector is reversed for some weird reason, so the polarity is inverted. connect the wires from red connector, to red fan 1, black fan 1 to red fan 2, black fan 2 to black connector.

Put the 8 M3 Screws in the holes of the fans, and put the fans in the duct model while carefully screwing the nuts in with a hex wrench.

Pop on the print using 2 of those m3 screws, screw in the print on the right side of the extruder.

Lastly, plug all of it in, and test the fan and CR-Touch before starting any prints.

WARNINGS!

Try not to prevent any of the fans from spinning, the other fan will overvolt for a bit, it most likely won't cause damage but will shorten the lifespan a bit.

Turn off the printer before installing any 3rd party upgrades provided by anyone, you will risk permanent damage and injury if you don't.

Be careful when soldering, it's just important to not toast your hands.

By the end of it you should have an amazing cooling solution that can bridge across the whole build plate DIAGONALLY.

Make sure to use a silicone sock!!! Your cooling will cool down the hotend way to much, and your printer will beep at you.

Thank you for reading this! If you do perform this mod, be sure to post a make.

To note, if you can, buy 2 5015 Fans instead and make your own cooler, it'll be a lot smaller and efficient.