Dichroic Lamp... LEDs But No RGBs

Ho there! I made this beautiful lamp by hacking two things: a lamp shade and a down-light. So yes, there are LEDs in the down light but all the colors come from the dichroic voxel sphere that rests a' top the lamp. I struggled through the design process and the evolution of the idea but now you could make it using very few tools, and very little time.

These are the two main ingredients:

LED Down-light from Leroy Merlin (it's a DIY store)

KARISMATISK lamp shade from IKEA (it's a meatball store that also sells furniture)

Post Publication Update: A very good point has been made in the comments by VinayDand that if you can't or don't want to purchase the lampshade for this project you can get dichroic film on line and apply it to a sheet of thin pliable plastic such as PET (what plastic bottles are made from). I'm not sure how the results would be but if you can do it that way you won't be restrained by size like I was. I preferred the lampshade option because I have an IKEA store very close by and there is no plastic supplier in my area that I know of.

After that I also used the following materials but you could switch them out for whatever will work for you:

2 Meters of blue fabric covered electrical cable

1 Black Plug

1 Black Switch

1 Black Cable trap

5" x 5" (12 x 12 cms) Piece of 5mm plywood

5" x 5" (12 x 12 cms) Piece of 0.8mm clear plastic, such as polipropelene

4 Black allen key screws M4x20

Tools I used:

Printer

Craft knife and steel ruler

Cutting mat

Scoring knife (blunt knife)

Screwdrivers, cable strippers and pliers

Drill, drill bits, M4 screw thread tapper

Jigsaw

Masking tape

Glue

If you don't want to hear my woes just skip on to the next step.

Back with another cube obsessed instructable project! When I made the Paper Voxel Sphere I was left smitten by a beautiful x-ray visual of the piece as a 3D solid in autocad. I thought to myself: This is going to be my next project A TRANSPARENT VERSION!

Well, it's been a couple of months since I did that project and I was playing around with different ideas but not enough of the project was working to push ahead with a final design. I was going to use filters for the different colors of the shape but I was weary of how dark they might look when overlapping or depending on how the light would catch them they might not have all the complex layers I saw in my autocad drawing. The discovery of Dichroic film was a break through moment. I could see that this single material would give me all sorts of colors when the faces are set at 90º angles to one another. But finding the right material to back it onto was proving difficult. I also spent ages on the idea of making a frame from soldering brass rods together but there was just too many intersections. I was running out of impetus. The idea of finishing the project any time soon was fading. I easily made another paper (cube) project in the mean time and I also churned out another lighting 'ible. Some things just fall into place but with this project, it seemed more like flogging a dead horse!

Then, the perfect material let me go ahead and complete the project: a sheet of ready made dichroic plastic I found it in an IKEA lamp. Its a limited edition product by fashion designer Zandra Rhodes. It's a drum shaped lampshade with a continuous strip of PET with a dichroic finish. The lamp idea is okay but its packaged, of course, as a flat pack and the plastic is all bent out of shape :( It doesn't do the design justice but what did I care! I just wanted to use the material for my light. If the plastic wasn't so bent I might have been able to make a bigger light fitting but anyway, it all worked out in the end :) I'd rarther I didn't need to pay so much money for a lamp I'm going to take apart but I won't be throwing any of it away. I'll keep the rings for some other lamp project and the rest of the material can be used for many different things

Use the first template to make a mock-up paper model. If you fold this into the shape of the shade it will help you fully understand how the assembly works and you can keep it by your side as a reference when you go about making the real one. cut it with an exacto knife and score the fold lines with the blunt knife. This blunt knife I'm using was made by a friend from a piece of aluminium. The difficult part of this design is the way some of the faces are joined together by very little material across the corners. You have to leave a minimum amount of material so that it doesn't distort the overall shape but if you cut it too close to the corner it might break off completely. Again, this is why you make the paper mock-up first.

The second print-out acts as a template for cutting out the shade.

Like I said before if the plastic wasn't crammed inside its flat pack box you could make a bigger size of the voxel sphere piece but it gives us lots of leftover material which is good for practicing on. IKEA says the material is PET plastic. It must be about 0.5 mm thick. It's not hard to cut by hand but it's not as easy as cutting paper either. You'll have to make a few passes and its very easy that the steel ruler can slip off it's mark. So like with most precision work, take your time and be careful.

First, cut out the out line.

Next, drill all the holes.

Lastly, make the cuts between the holes.

BE CAREFUL! There's very little room for error here. If you over shoot the hole you could cut through to the next hole and the pieces will separate. As you can see in the detailed photo here, on the left, I almost cut right through the hole on the right. To avoid this from happening, always cut away from the holes towards the center of the cut line. Any bit of damage to these tiny circle holes could get worse when you go about folding the pieces because at this point it gets very stretched out of shape

To fold the plastic, we first need to score the fold lines with a blunt knife. This is quite boring. You just have to concentrate and get through it. You'll need to apply a lot of pressure and make a number of passes because the PET plastic is very tough. Align the steel ruler with the fold liines just like when cutting and run the blunt knife along the ruler.

There are 4 groups of 3 folds each. Work each group separately. I've indicated the valley and mountain folds on the print-out. Notice that there are both mountains and valleys along the same fold line. Start by folding the lines into a mountain and then back into a valley. Do all three lines of each group. Now that you've made the plastic move both ways, each part will move easier to where it needs to go. When all the groups of folds are done you should have the voxel sphere shape we're looking for.

For nearly all the joins I cut a 10 mm strip of the leftover dichroic PET and put double-sided sticky-tape on it. But that wasn't enough to keep the big join in place because it was quite curved from having been squashed the IKEA flat-pack box. This was a problem for the big join. The double-sided sticky-tape wasn't strong enough to overpower the curving plastic. So for the big join I used a large rectangular piece and used a clear contact adhesive. Then I clamped it to my work bench for a couple of hours.

Last thing to glue will be the translucent base to the bottom of the voxel sphere shade. But I needed the base to locate the holes on the light fitting so I didn't glue that to the rest of the shade until I had finished converting the downlight to an uplight!

It took me a long time to decide what light source to use. I was going to use a normal bulb but it blocks some of the view of the reflecting colors inside the voxel sphere. When I broght the bulb out to the edge of the shade it seemed be asking for a light just coming in from below. And besides, up-lighting is very dramatic!

I printed the base template for the voxel sphere and cut it out of some polypropylene sheeting I had leftover from my last lighting project. I punched out 4 mm holes in the corners then traced those holes onto the aluminium frame of the light and drilled 3.25 mm holes. If you do all of this by hand it won't be exact so I marked one of the holes on the polypropylene and the same one on the frame because that way I'd be able to re-align them afterwards. Then I threaded the holes for M4 screws. I drilled a 10 mm hole in the side for the cable trap.

These black allen-key screws are easy to screw by hand which is all you need in this case. I remembered I had these colored fabric cables in stock from years ago. The blue fabric goes well with the dichroic plastic and the plug, switch, cable trap and screws are all in black.The base is white but what heck... Works for me!

I put a plywood base underneath the lot. I cut a 12 cm disk out of 5 mm plywood and added two little blocks with 3.5 mm holes that come up to coincide with two of the four screws.

So last thing to do was to glue the transparent plastic base plate to the rest of the plastic shade. I used the clear contact adhesive for that too. Then I screwed the shade onto the light fitting and it was done ;)

All together I'm very satisfied with the results. When I made the paper voxel sphere I knew it was difficult. This lamp, although based on that design is probably easier to build.

I used "this light" and "that lamp shade" the instructions might need to be varied a bit if the case is that you use "this other light" and "that other lamp shade" but the template can be re-sized to suit whatever materials you get your hands on to make it work for you.