Introduction: Light Under the Fan Casing of a 3d Printer.

About: I have been working with art and designs. I like to improve my 3d printer and design accessoires for it. I 3d print it myself. Next to these designs, I make art and I tend to embed these with electronics in 3d…

The reasons for light under the fan casing of a printer carriage especially when the print is not bigger then the fan casing. I want to know what the nozzle is doing in the first layer and in real time for reasons is my bed adhesive enough or did I level my bed well. Although the 1st reason can also happen after a few layers done. An other reason is that especially with petg to much filament is extruding and it sticks to the nozzle, and you have got to pause the print to wipe it of the nozzle or begin again when you cannot lower the temperature in your 3d sliced file in real time. Or support has not been adhesive to the bed. The whole print has got to begin again. For all those reasons a nozzle in light helps a lot especially with chinese 3d printers, creality, ender3, geeetech and sofort. I 3d printed 2 parts for it, the led holder with a thrench in the middle for putting the wire and the resistor in it. The magnetholder to attach the magnet holder on the metal fan casing. I printed it in 2 parts because a big overhang would appear, when I 3d printed it in one part, and that the magnet without magnet resistance through the plastic fits well on the metal casing. I chose a resistor of 120 ohm on a max 8 volt, 2 times a 18150, this will give a very bright light. Measure the current with multimeter between batteries and resistor. 60 mill.amp is max. With such capacity one charge of a battery will last long. I include 2 .stl files the magnet holder and the led holder. They have been printed in petg, but I think you can use pla as well. You can mount the part from the corner toward the middle en in a diogonal way, both posititions will leave the holes open for letting the air of the fan out. You cannot use it with a large print as the light will travel over the clamps and there is no space for that. Use your clamps as wide as possible. When you use no glass bed but a much lower build plate, like a pei sheet or magnetic sheet, the light is just a liitle bit lower than with glass of 3mm.



  • Neodym magnet 20mm
  • Flexible wire
  • 120 ohm resistor
  • White led 3mm
  • Filament, if you print it yourself
  • Clips
  • Heatscrink tube, isolation tape
  • Solder tin
  • 2 zip ties
  • Battery holder for 2 18150 in series
  • 2x stainless steel screws 1,2mm in diameter, max 8mm in length.
  • Glue
  • Tools
  • Heat gun
  • Solder iron
  • Strip plier
  • Plier
  • Handhold
  • Special plier or vice to clamp wire ends + isolation in clips.
  • Screw driver for stainless steel screw 1,2mm
  • Threaded rod
  • Glue gun

Step 1: To Make a Spiraled Wire From Your Flexible Wire.

When you have twisted the 2 wires, wind them around a rod and fasten the beginning and the end of the wire to the rod. You can push the rings towards each other. Then you use the heatgun and warm the plastic, if you can turn the rod with the wire. Move the heatgun over the wire and turn the rod. After a minute or 2 you undo the fastening and examine the rings. You will notice that the material used in flexible wire can differ. If you use wire not being specified for this function, you end up with a spiraled wire, which I made. But good enough for the purpose, see picture. You have to wind the spiral wire around the wires, going to the hot end and clip them to the led holder with clips.

Step 2: Note About 3d Printing the Led Holder.

This part shows support where the wire goes through the hole and support for the hole where the led fits in. The support for the lower hole begins begins at the foot of the part, the support for the top hole, where the led fits in begins on the building plate. Support was easily being removed with a trimmer from the outer shell. You can also use a small hobby knife to remove it. The other pictures show the assembly of the 2 parts. The holes have got to be drilled from the holes in the magnet holder, drill first 0,7mm all the way through both parts, then set the screws with a diameter of 1,2mm in the 3d printed holes of the magnet holder and tap the thread for the 1,2mm stainless steel screws, with those screws themselves. And the last ones are the stl files for printing, where all meshmixer support can be seen in the led holder. Some how my stl files do not show up in my publication, if you want the files mail me at

Step 3:

The battery holder for 2 18150 batteries is being attached with 2 zip ties to the extrusion above. The second picture shows the switch on the batterie holder. The third picture shows the cutouts in the batterie cover, so that it still fits as a cover on the batterie holder.

Step 4: All the Images

Step 5: 2 Stl Files.

The 2 stl files for the whole part.

Step 6: