"Good Darts!" LED Neon Sign

Designed for standard 3V LED filaments.

A tip in advance regarding filaments: If possible, avoid "cuttable" LED filaments. These usually have both power terminals on one side, which often causes the first centimeters to glow significantly brighter than the rest. In my experience, non-cuttable LED filaments with positive and negative poles at opposite ends provide much more uniform brightness.

The fully assembled model (glued and snapped together) measures 35 cm wide, 11.5 cm high, and 4 cm deep incl. the base. I would not recommend scaling the model without making adjustments, as the dimensions of all snap-fit elements (LED holders, lettering, and the base lid) will no longer fit properly.

The base of my personal version features three mounting holes for a power jack, an on/off switch, and a dimmer with a potentiometer. I have also uploaded a clean version of the base without any pre-made holes.

When running at full power via a power supply, LED filaments can get quite hot. However, they stay much cooler when running on rechargeable batteries (due to the lower 1.2V per cell). Because I use a power supply, I printed all parts in PETG. If you plan to use rechargeables, PLA is sufficient.

Practical Assembly Tips
The lettering: You must print these in white or light-colored PETG or PLA. Enough light passes through to create a beautifully even diffusion. Avoid transparent materials, as you will see the individual LED beads inside, which ruins the neon effect.

Wiring: 3V LED filaments must be wired in parallel. A series circuit will not work.

Power Management: If using a power supply, I highly recommend using a PWM dimmer to run the filaments at about 80 to 90% brightness. This prevents them from overheating and significantly extends their lifespan. Resistor Alternative: You can use a 5-ohm power resistor (min. 5W) wired in series (e.g., between the power supply's negative pole and the LEDs' common ground).

In certain areas, the filaments need to be laid in loops. To prevent these spots from being too bright, ensure one part of the loop is tucked into the upper clips while the second pass goes through the lower recesses.

If you are using non-cuttable LED filament but still want to create a clean color transition exactly at a letter, use black heat-shrink tubing. Slit it lengthwise and then slip it over the section of the filament that you want to mask.

It can be a bit fiddly, but always route your connecting wires through the lower recesses of the base so they don't cast shadows through the diffusers.

Have fun printing and Good Darts!