Half the Lamp, Twice the Fun

Have you ever seen these scenes in the terminator movies where they are coming back from the future ? You know, where the sphere into which they appear disintegrating everything in its path. This was part of the inspiration for this lamp.

In this instructables, I will show you how I have converted a lighting lamp into a decorative lamp. I have used a relatively cheap lamp, the Ikea Tertial

I chose a color scheme that works fine but, should you try this project for yourself, have fun with it 😉

3D printer

4 40cm of C aluminium extrusion

Superglue

Spray paint Black & white

Large paint brush

Red acrylic paint

One Tertial lamp

11 M4*8mm screws with nut

USB cable + charger

Painter’s tape

Metal saw

Metal file

The goal here is to recreate the arm and to have it looking as if it was a square extrusion cut in half along its length. We first cut the raw aluminum C extrusions to the length of the original arms it will be replacing. File them to the exact length and to debur them (for an end result as clean as possible).

Then, to prepare them for the paintjob, we need to clean the aluminum extrusion in soapy water. This step is important and a little bit easier to do prior to drilling the holes for the screws.

Measure le location of the holes on the original arms and transfer them onto the new aluminum ones. My measurement show that the center of the holes are in the middle of the width of the arm and 5mm from its extremity.

Painting the new arms is a 3 step process

First, we will paint the interior of the C extrusion, cover the exterior with the painter’s tape making sure that you do leave any gaps. In a well ventilated area, you can then proceed to painting the interior of the arms in white (there is plenty of tutorials online showing how to spray paint to get the best results).

Second, once the interior paint has dried, mask the interior of the extrusion with painter’s tape, do not forget to mask the holes drilled in the previous step. Paint the exterior with the black paint.

The third and final steps consist in painting the imaginary “cut line” of the lamp. Painting the cut line highlight the feature. Mask (once again with the painter’s tape) enough on both sides (interior and exterior) of the C extrusion to get a consistent cut line and paint it with paint brush and acrylic red paint.

The most interesting looking part of this lamp is going to be what I am calling the “head mount” comprising of the lampshade (2 part) and lightbulb.

NOTE: some parts of the lamp are chiral (meaning that they are symmetrical but cannot be exchanged to the other side of the lamp). This mean that at this point in the process of building the lamp, you should choose which side you will be building (you can also build both lamp).

With the metal saw, we will try to cut the lampshade as much as possible in the exact middle. The lampshade in this lamp is actually in two part and it is much easier to cut the bottom and top part of the lampshade separately.

For the Top and bottom parts of the lampshade, mark the middle of the part put it on flat surface and saw it with the metal saw. One thing that you have to be carefull with is to not deform the parts whilst cutting. You will deform them a little but probably nothing that cannot be shaped back.

Clean the edges with a metal file.

The interior of the bottom part of the lampshade is already shinny white and will not require additional painting. The exterior however is going to have to match the color of the new arm and as such, will need to be painted black. Tape the interior of the lamp shade and, in the same way that you painted the exterior of the arm, paint the exterior of the bottom part of the lamp shade black. Once dry, like what we did on the arm, mask the interior and exterior and paint the “cut line” of the lampshade.

Repeat the exact same process with top part of the lampshade but also paint the interior of the part white.

The last part that need to be cut in half is the part that connect the arm to the table. As you did for the lampshade, cut it in half with the metal saw. Using once again the painter’s tape and the process describe for painting the arm, paint the exterior of the part black, the interior white and the cut line red

I have made a 3d printed part to help the arm stay in place in the plastic arm holder, you find it here

It is worth noting that the plate in the 2 other joints do not need to be cut just the painted: the exterior in black, the interior in white (and, of course, NO cut line for those two parts)

First, remove the plastic bulb from the rest of the lightbulb (The original PCB with the led is thrown away), you can then cut the bulb and the rest of the lightbulb in half.

Drill 2 holes for the wire that we will install later on to power leds. Those holes should be in front of the holes through which we will pass the wire.

Only the cut line of the lightbulb is painted with the paintbrush and red acrylic paint

You can choose to make a custom PCB, but for something as simple as this lamp, I just 3D printed (and painted white) a half circle (with the same diameter and height as the original PCB we removed) that you can find here . I used some LED that I had laying around but they were on a PCB with a form factor incompatible with the shape of the lightbulb so I removed them from their PCB and glued them onto the 3D printed half circle. The 3D printed half circle has a hole corresponding to the shape of the LED, this holds the LED while I solder them to each other and when I solder the wires.

The lightshade mount is made of 2 parts, the original metal bit (cut in half, cut line painted red) and a 3D printed part to replace the original parts that links the metal bit to the rest of the arm. This 3D printed part is painted white except for the cut line painted red. You can find the model for this part here

Use .75mm2 black and red wire (the black and red is really for aesthetic purposes). Pass through the wires trough, first, the lightbulb-holder and then to LEDs inside the lightbulb, solder the wires to the LED.

Then, glue the lightbulb in the lightbulb-holder and the light-bulb-holder inside the lightshade (at the top) while making sure the wire comes out the top.

Replace all the original screws with M4*8mm. You can now mount the entire lamp with the screws. Then tuck the wire inside the top C aluminum extrusion (red side of the wire visible).

To power the LED, I am using a usb charger (for security reason, you have to use low voltage to power this lamp due to the fact that the lightbulb is open).