Salvaged Street Light Conversion

I salvaged a few decommissioned street lights from our local tip — battered but mostly intact. I suspect they once lit the main street of our town, and now they’ve found a second life as garden features. A bit of restoration, some creativity, and they’re back in action.

Old banged up street light/s

A 3D printed bracket

Gal water piping and elbows

Paint, sealer, glue, sandpaper, cleaning products

8x8 LED matrix module - mine came from here

MCU dev module - I used an RP2040 from here

DC convertor from your AC/DC voltage to 5V or 3.3V

The first step is to clean the street lights up.

Using a small hammer with a rounded end, I gently tapped them back into shape. Since they're made of aluminium, it wasn’t too difficult to get them reasonably straight. For the edges, a small spanner worked well to press and bend things back into line.

Once reshaped, I sanded the entire surface with 240-grit sandpaper to give the paint a good surface to adhere to.

1. Exterior: spray-painted in matte black
2. Interior: finished with a matte burnished copper spray for contrast and warmth

Inside the housing, I removed the ballast and all the original electrical components used to power the high- or low-pressure sodium lamp.

I’m not sure if this is standard, but in my case the globe holder was mounted on an aluminium bayonet. I kept this in place and later repurposed it to mount the new light source.

The electronics setup is fairly simple. I used an 8×8 LED matrix so I can fully control the colour temperature and create custom lighting effects.

You'll need a DC-to-DC converter that matches your input voltage and is rated for the power required at full brightness. In my case, the module is quite small since I never run all the LEDs at full power.

Important: Don’t rely on the onboard voltage regulator of your dev board to power the LEDs — you may end up like the second picture...

Before wiring everything in, make sure to complete the next step.

I designed a two-piece plastic holder to adapt the housing to fit a Glowbit 8×8 LED matrix. The holder sandwiches the LED module carrier and insulates it from any surrounding metal parts.

The 3D print files are available on my GitHub, along with the FreeCAD source file in case you want to tweak the design for your own setup.

The matrix clips neatly into the square cutouts and sits flush with the top surface. Once in position, I glued a printed ring over the matrix to keep it secured.

And finally, I covered the back of the module with electrical tape to protect the contacts.

Mount the LED matrix into the printed holder so it sits flush with the surface.

Glue the ring over the front to keep the matrix securely in place.

Use hot glue to fix the DC-DC converter and microcontroller to the back plate.

Make sure all wiring is secure and insulated (I used electrical tape on the back of the board).

In the image above, the right-hand unit shows the matrix clipped in, before the retaining ring was glued.

Glue the matrix and holder assembly to the aluminium bayonet from earlier. Since this section is sealed, I used silicone to seal where the wires pass through to maintain weather resistance.

You could swap in a Wi-Fi enabled microcontroller and go wild, but for this garden application I’ve kept it simple. The Python code just sets all LEDs to a single RGB value, allowing for basic control over colour temperature and brightness - or even effects, if needed.

In our case, we (meaning my partner) wanted an exact match to our existing garden lights — about 3250 K. The RGB setting of (255,139,21) does the trick, drawing around 250 mA from the DC regulator.

I used gal water piping and elbows to get the bracket look and function I wanted. Standard plumbing bits were used to attach to the light to the gal.