This is a simple tutorial on how to add a hidden bright led light to the most common 3d Printers, that have an aluminum profile (Ender, Neptune etc.). Do this at your own risk. Be sure that the printer is off and the power cable is unplugged.

Supplies

24volt 2meters High Brightness Led Strip. I used this one from Aliexpress : https://bit.ly/4b9bIkr

Wire Cable. I used this one from Aliexpress: https://bit.ly/3UVdSyn

KCD 1-11 Rocker Switch . I used this one from Aliexpress: https://bit.ly/3QEVA1U

Step 1: Check the Voltage of Your Power Supply and Determine the Voltage of the Led Strip

First of all you have to check the voltage of the power supply of your 3d Printer. Of course, not all 3d printers have the same power supply, but a lot of them have an 24 volt power supply. This is a very important step in order to decide the voltage of the led strip you are gonna purchase.

You can find the voltage rating of your power supply, in a sticker that's on your 3d printer's psu. It is usually on the side of the psu. I have a humble Neptune 2, which uses an 24volt psu, so I am gonna choose a 24 volt led strip. In other case, choose the voltage of the led strip accordingly to the voltage of your psu.

Step 2: Measure the Frame and Solder the Wires to the Led Strip

You have to measure the total length of the frame, in order to decide the length of the led strip you will need. Once you find the distance you must cut the led strip accordingly and solder the two wires at the one side. Be sure to leave enough wire to make our job easier, especially for the red wire depending on where you want to install the on/off switch. In my case I wanted the led strip switch to be just under the printers on/off switch, so I made sure I had enough to go all the way around.

Then, solder the wires to the led strip. The red at the positive, the black at the negative.

Step 3: Install the Led Strip Inside the Aluminum Frame

This can be a little frustrating. First unscrew the screws of your spool holder and remove it. Then remove the screws on the top of your 3d printer in order to take apart the top aluminum frame. With the top aluminum frame out of the way, insert the led strip on the opposite side of where the psu is located, starting with the end of the led strip WITHOUT the wires. We want the wires to be next to the psu, in order to connect them easily.

Left side: Be sure that the led strip goes all the way down, under the wheels that are used in order to move the print head aluminum frame up and down.
Middle side: Be cautious with the corners that connect the side frames with the top center frame.
Right side (Psu side): Again be sure that the led strip goes all the way down and that the cables are long enough to reach the psu unit easily.

Step 4: Connect the Red Wire to the Switch

First of all be sure to double check that the printer is off and the power cable is unplugged.

I used a KCD1-11 switch in order to turn on/off the lights, because I didn't want them to be always on when the printer is working. I wanted the led's strip control switch to be just under the printers on/off switch.

I used this 3d printed mount, which you can download: https://bit.ly/3JYsJlc

Install the switch into the mount. Then solder the end of the red wire coming from the led strip to one of the contacts at the back side of the switch. Then, use a new red cable, solder it to the other contact and make sure its long enough in order to reach the psu unit. You can use the aluminum frame in order to do some kind of cable management.

You can use heat shrink tubes as I did . I have purchased a kit from Aliexpress (https://bit.ly/3WBhU01) and I use them for my projects. Otherwise, some simple electrical tape will do the job just fine.

Lastly, just slide the mount into the aluminum frame and run the wire to the psu.

Tip: You can use black cable in order to do this in order to be less visible inside the aluminum frame. Just be sure not to confuse the positive and the negative cable.

Step 5: Connect the Wires to the PSU

Again, make sure that the printer is off and the power cable is unplugged.

Unscrew the screws of the PSU unit and take it out of the 3d printer's frame. Locate the front side of the PSU where all the cables are plugged into the unit . It should look like the one in the pictures.

We need to connect the red wire that comes from the switch under the V+ sign, in one of the empty spaces without cables. Again , we need to connect the black wire that comes from the led strip under the V- sign, in one of the empty spaces without cables. Just unscrew the screws, insert the cables and screw them again. Make sure they are well connected.

Reinstall the psu unit back to the 3d printers frame.

Tip: You can use SV Type Wire Spring Terminals for better connection, if it happens to have some around. I have bought this kit one Aliexpress (https://bit.ly/3WGxS97) some time ago and it comes in handy for projects like this!