Introduction: Fiber Optic LED Chandelier

About: Light tinkerer. Paris / San Francisco / London

The fiber optic LED chandelier was a cool project to bring together curiosity of hobby electronics, light and material exploration. This board gives you a general idea of the vibe I was going for.

Isaak shot and crafted a beautiful video for this piece. There's also a crappy one shot by me.

Few words about material exploration and choices...

I picked black opaque acrylic for the base of the chandelier to give the lights underneath a chance to reflect overhead. If you make yours you'll see how cool it looks when the shimmering particles reflect like a starry night sky ;)

The trick to getting even amounts of light to travel through the fiber optic strands is to bunch them together from the start and have an ultra-bright LED shining on that 'origin' (more on that later). Once the light hits the end of the cable it is lodged in a clear cast acrylic sphere. Warning: do not use glass marbles for your spheres!! I almost lost an eye drilling into one.

The overall design below the base was inspired by a trip to one of the California Academy of Science's NightLife events (in San Francisco, CA). There is an aquarium with a tank full of jellyfish which they light up from the top downwards in the water. The cutting of the strands was directly inspired by the anatomy of the jellyfish.

Oh yeah one last thing. If you do end up making one and want to transport it from place to place, tape together a couple sections of fiber optic strands. Else your day is doomed to be spent untangling the whole thing!

Step 1: Tools & Parts

Parts

  • Pre-Cut Fiber Optic Filament - 200 strands from The Fiber Optic Store
  • LED light engine - Ultra Bright 3W LED illuminator from The Fiber Optic Store (combo pack, approx $180)
  • Clear Acrylic Spheres - 5/8" width, 50 for $15.00 from Tap Plastics (approx $50)
  • Custom-cut Circular Black Acrylic base - 1/4" thick from Tap Plastics ($118)
  • Metal chains (25cm length) - Home Depot
  • Eyelet/washer, nuts and a carabina for the hanging setup - Home Depot.

Tools

  • Drill
  • Drill bit designed to drill into plastic (dimensions ⅛” thick) - Tap Plastics
  • Pencil
  • Compass
  • Epoxy glue parts A and B
  • Painter's tape
  • Little painting brush
  • Scissors
  • Small ruler

Useful resources

  • The Fiber Optic Store - the site looks straight out of the 90s, I love it.
  • Tap Plastics - their store is located in San Francisco, CA. They have everything.
  • ePlastics - although I did not buy from them, it's a solid resource to keep.
  • Jake Morton's Instructable was a goldmine of information when I began this project.

Step 2: Math

Before getting started, we need to figure out a couple of things (errr a lot of things actually).

So this chandelier is made to hang from the ceiling and look pretty at a party.

The drawing above recaps the situation described below:

What we want to know is how low the chandelier should hang, and how much each part of the chandelier should measure. What we do know, first and foremost is the ground-to-ceiling height, which is 4,5m or 15ft. If we think of a party scene, we know there are going to be tall dudes and women wearing heels. So your average human height is going to be more like 1,90m rather than say 1,75-1,80m. Let's round it up to 2 meters. Because it's a party with music people are likely to jump up and down and wave their arms in weird directions. So let's add an additional half meter so their dancing doesn't accidentally touch and tangle the low part of the chandelier. We'll probably need around 50 cm (19 inches) to set up the hanging system with the chains. Which leaves us a height of 1,5 meters (59 inches) below the hanging setup to light up the pretty spheres :)

Bottom line: the chandelier will measure very approximately 2 meters, with 50 cm above the base and 1,5 meters below.

Next, given the 200 fiber optic strands that came with the LED Light Engine and given the design goal, we need to figure out the diameter of the circular acrylic base.

I broke down the design into five different parts, it will make it easy to know how many spheres are needed for each part and what should be the distance between the spheres.

Imagine the following contour; actually, looking at my sketch will make more sense. From the center of the circular base, a line travels to the edge of the outside circle. That's the radius (= part 1). That line continues to travel alongside the circumference of the circle until it hits the point that marks half of the circumference of the circle (= part 2). Then instead of continuing along the circumference, it turns to re-enter the inside of the circle and travels through its whole diameter (= part 3). That line turns the opposite direction as before and performs a half-circumference turn (= part 4). We're almost back to where we were before; we re-enter the circle for only a radius-length line until we hit close to the origin spot (= part 5).

Bottom-line we have:

part 1, part 5 = radius,

part 2, part 4 = half-circumference,

part 3 = diameter.

I fiddled around with numbers to get the most accurate diameter length for a circle that would fit 200 spheres measuring each 1,6cm (or 5/8"). Long story short, a 24 inch diameter on a 30 inch circular base made the most sense. Math details below:

For part 3, the diameter, d = 61 cm. So d/(length of marble) = 61/1,6 = approx 40 spheres.

For parts 1 and 5, the radiuses, r = d/2 = 61/2 = 30,5 cm. Then r/(length of marble) = 30,5/1,6 = approx 20 spheres.

For parts 2 and 4, the half-circumference, C = πd = π * 61 = approx 64 marbles.

With this dimension, the total number of marbles on the chandelier is 208 marbles. With exactly 20 marbles on parts 1 and 5, 64 marbles on parts 2 and 4 and 40 marbles on part 3. The 8 extra marbles (because 200 fiber optic cables) are not even needed because of the ‘gaps’ between the parts.

This circle of 30 inches in diameter (76.2cm) with an ‘active’ circle of 24 inches in diameter cost approx $118 to be made at Tap Plastics.

Ok. Enough numbers. The next steps are more fun I promise

Step 3: Drilling Into the Acrylic Spheres

It's tricky to drill directly into spheres because well, they roll.

To counter the problem, my awesome colleague Mike designed and 3D printed these cubes. With the center area empty, it was possible to lodge a sphere and keep it in place there during the drilling. I went through 6 or 8 cubes, they wear out pretty fast.

The drilling was easy but time-consuming. For every marble it was a 10sec process. I made sure to stop drilling 60% in as to avoid a hole on both sides.

A day of drilling later - all 200 spheres are ready for the next step.

Step 4: Drilling the Acrylic Base

Distance between each holes = approx. 1,6cm

I kept the adhesive protection during the drilling for two reasons:

  1. It's easy to write on it to get accurate markings for the drilling spots;
  2. did not want the black acrylic base to be covered in dust or risk getting damaged.

I kept the math handy. It looks messy but the papers in the photo above tell you how many holes per area* needed to be drilled.

*in Step 1: Math I explain how I organized 'areas' of the design. In short, those are: 1 diameter-length area, 2 radius-length areas and 2 half circumference areas.

Step 5: Powering the LED Light Engine

What I referred to as the 'origin' of the light is the junction of all the fiber optic strands.

The illuminator Model LLE-003 TW is great because all of the light source is directly poured into the fiber optic cables. Essentially it's like a well of light. Thus there is no ‘light waste’ reflected on any surface..

The engine requires 12V DC so you can plug straight into your standard 120V wall plug. For reference, the dimensions are L:7 1/2" x W:3 1/2" x H: 2 3/4".

The engine comes set up with four DIP addresses. The four switches are located in the back of the engine, close to the power jack.

For reference, the following numbers of this light engine correspond to the following light intensity:

  1. shimmer intense
  2. shimmer average
  3. shimmer low/very subtle
  4. no shimmer

Personally I like number 2; it shimmers subtly.

Once you have made sure the light engine works, run each strand through the holes of the circular acrylic base you have drilled (photo in next step). In the next step you'll see how we mount the whole chandelier to the ceiling.

Step 6: Making a Support Structure

A colleague of mine Patrick helped me a ton realize this support structure for the chandelier. It consists of drilling four holes like a square on the acrylic surface and placing for each a eyelet/washer/nut setup.

From each corner, run metal chains (25cm length) and bring them together in a carabina at the top. This setup will also hold the LED Light Engine. The engine comes with two holes you can run the chains through. Don't be afraid of this setup looking too bulky, it isn't visible from the ground.

In the early phase of the project, I anticipated the distance between the base to the attach point (= the carabina) to be 50cm but it turned out to be 30cm (12 inches).

This is heavy. Get someone to help you. In this case, we looped the chains around a sturdy wooden bar that sat on the corner walls of a ceiling-less room during the working process.

By this step you should have the circular acrylic base hanging from the ceiling with the LED light engine powering the fiber optic strands running through the holes of the base. Next we'll give those fiber optic strands some shape, I call it the 'haircut'.

PS: don't pay attention to the strings in the second picture - that was a early prototype. Do pay attention though at how the chains lock into the carabina.

Step 7: The 'Haircut'

This step is specific to this chandelier and you can approach it any way you want.
It's the cutting of the fiber optic cables. Just like we say before, there are five different parts that constitute the design. You need scissors and a small ruler.

In this specific case,

We know the longest strand (let's call it L) measures 1,5m from the base and is located at the center of area 3. From that point, take approximately 1cm off every strand before and after that. So the strands before/after L are going to measure approx. 1,4m and the ones before/after those last ones 1,3m and so on.

Do that all around the piece. My advice for keeping all the 'hair' somewhat organized is to wrap the different areas in painter's tape. I liked doing this step very much, it's quite meditative. In the next step we'll add the spheres to the chandelier by gluing them to the fiber optic strands.

Step 8: Gluing & Drying

Now that each sphere has a hole. It is time to insert a strand of fiber optic into each sphere and seal it with some glue. I used a little paint brush to make the process cleaner.

You must use epoxy glue. Mix equal parts of A and B in a disposable container with a toothpick or little paintbrush. This glue takes 6-12minutes to dry. It would take way to long to hold every single sphere for that amount of time. A neat trick: use painter's tape to wrap the fiber optic cable and the sphere together. I let it sit overnight just in case. Peel off the painter's tape gently. Approx 10% of the spheres won't make it, so set some time aside for gluing part 2. Have some extra spheres lying nearby.

We're almost done!

Step 9: Lights Off!

The chandelier is ready to be lit!

We moved the chandelier from the corner space to a bar/club environment. In the space I ran a 20 feet extension cord from the LED Light Engine to the nearest plug in the ceiling. The lights ran for a over 10 hours just fine. In the description of the engine it said the bulb goes for 100,000 Hours.

Again, an immense thank you to Isaak Lê who shot and put together this gorgeous video entirely. His beautiful shots really captured the vibe and he is a humble total pro. All of the beautiful pictures from the Intro step are stills from the video. Thank you Claude Shade and Quinn Gravier for photographing the chandelier professionally.

While making the chandelier a depressing yet exciting thought occurred to me. In a couple of years there will be so much pollution in the sky, starts won’t be observable and we’re going to make starry night ceilings to compensate.


PS: I'd like to point out that this was the last of many many prototypes. For conciseness I kept the documentation to only this version. For additional versions of the chandelier message me and I'd be happy to share my previous explorations.