DIY 3D printed recessed LED fixtures
 

[EDIT] sorry, some of the pictures are upside down.

So, the original 1980s light fixtures in our upstairs hallway have always bothered me a bit. They just look... well, so 1980s. Since I've built fixtures out of LED modules and strips for both my office and kitchen, I figured why not replace those too. For the hallway though, after talking it over with the wife, we wanted recessed lights.
I did a little shopping and found several different options - all of them outrageously expensive, $30 and up. Since we wanted two rows of 5 each along the hall, that could have gotten expensive real quick.

Back in September, I got a 3D printer for my birthday. So, earlier today I set out to design my own simple recessed LED fixture, and about an hour ago I installed the first two!

The fixture itself consists of two parts, top and bottom. The bottom is sized so that it exactly fits into the hole my 65mm hole saw makes into the drywall, tight enough to not need any adhesive.

http://ecorenovator.org/forum/attach...1&d=1387771922

The top is designed to thread the wires of one of my go-to LED modules (4 5050 type SMD LEDs in one small module), through and glue the module itself to the center strip:

http://ecorenovator.org/forum/attach...1&d=1387771922

There's a 1mm lip around the inside of the bottom half, designed to catch a piece of acrylic cut to size with the same hole saw. It fits in perfectly and lays on top of the lip, again without needing any adhesive.

http://ecorenovator.org/forum/attach...1&d=1387783777

Then the top just slots into the bottom piece.

http://ecorenovator.org/forum/attach...1&d=1387783777

So, I just cut a hole in the drywall from below, push the bottom part in. Then wire the modules from above, and just drop them into the fixtures from the attic. It takes about 10 minutes to wire and install two of these. They're extremely low profile (only about 16mm tall), and since the LED modules run on about 0.8W each, heat is negligible.

http://ecorenovator.org/forum/attach...1&d=1387783777
http://ecorenovator.org/forum/attach...1&d=1387783777
Here's a shot of the bottom half of one being printed:

http://ecorenovator.org/forum/attach...1&d=1387783777

You're photos are very nice, but there is nothing in the photos that warrants an image size of 3049 x 2287 pixels. 800 x 600 pixels would be more than enough resolution.

Resizing is easily done with whatever basic graphic editor your computer came with.

It will make uploading less of a chore for you, and less of a chore for all the people who might click on your post.

It took me about 5 minutes for your images to come in... long enough for me to write this message to you.

Bandwidth isn't free.

-AC

Apologies. I took the shots on my cell phone and just uploaded them without checking size first. I'll edit the post with resized images.

All fixed!

That is really cool! I wish I had a printer. Oh, the things I could build!

There's just one thing. You say the $30 per fixture X the number of fixtures could end up being too much, but you have a 3D printer?!?!

Hah, good point!
I got the printer anyway, simply because I wanted one (and oh how useful it's been already!). The kit was $399, and with these lights and some of the other things I've printed, it's more or less paid for itself already.
I'm not necessarily saying that the 300-400 bucks for the lights would have been completely unaffordable - but for what you get, which is essentially a can with a light in it, it's ridiculously overpriced. I'm a fan of balance - essentially, the price/value ratio of the factory made fixtures just blew my mind, especially since it's I managed to make ones that work fine and look nice at a cost of about $1.50 a piece - and that's including the light!

Of course there's the issue of the rating. I can't very well get my printed housings rated for direct insulation contact, although I know full well that they'll never get hot enough to be a problem. In the end, that might mean that if I ever sell this place, I'll have to place some 6" pipe or so around each of the fixtures in the attic and sacrifice some attic insulation performance for the future owner :P

Pretty cool stuff! Thanks for sharing. Lucky guy with a 3d printer... :)

Are the wire connections contained? It looks like the wires leave through the top and are exposed to the attic. All wire connections need to be in a box.

This is really great!

I bought a little CNC router kit (ZEN) just to see what this CNC thing was all about. I learned a lot from the experience. Enough that I am collecting parts to make my small milling machine CNC, too.

So, back to the ZEN, I have all the hardware working under computer control, and I think it should be possible to adopt it to 3D printing.

I'm impressed that you've been able to fashion something as utilitarian as a light housing!

So far, I've just seen people make hollow spheres and pretty plastic spirals and tiny tea pots with removable lids.

I'm not being ironic when I say that making utilitarian items is a big step forward.

Awesome.

-AC

That is waaaaaay cheaper than I thought you were going to say! I've only seen them in the thousands. Basically your printer just paid for itself with this project. :thumbup:

Even 12V connections? If that's the case, I'll have to modify the top so it can hold the wire connection as well. Hmm... I wonder if I can make a wire connector integrated into the top...

I was skeptical when I first got interested in 3D printing, but then found things like this:

newest - Thingiverse

Some of these designs are ingenious. There's a surprising amount of useful stuff out there :)

So, I've read through everything I could find on low voltage electrical code. It seems my installation is a class 2 circuit. The power supply is 100W with two 50W outputs, which conforms with class 2, and the wire splices are in a location where they're not subject to inadvertent physical stress.
I can't find any requirements for wire splices for class 2 needing to be inside a box, but I'm certainly not a NEC specialist. Anyone have any more insight?

Still, I like the idea of having the connector integrated in the fixture top. I may get a bunch of Molex or lustre connectors and design the top part so that the connector can be integrated into the fixture top itself :)

That looks awesome. where did you get the 3d printer from?

It's a Printrbot Jr. kit I bought from MCM electronics. I think I got the last one of the version 1 PbJrs, they went out of stock as soon as I ordered mine :P
Printrbot.com sells a few different models, unfortunately all a bit more expensive than the Jr. V1.

I did not realize it was low voltage. That may be alright depending your local code. I like your idea about molex plugs. Sounds like a good compromize for safety.

So, I did some more research into what the code says about recessed fixtures. It seems that, regardless of the type of light used, if you want to put insulation on them, you have to get an IC rated canister on the top side. What makes an enclosure IC rated? Certification by an approved laboratory. Makes me wonder if I can send in one of my homemade fixtures to get them tested and certified, ha!

I just measured with an IR thermometer, and after 48 hours on with insulation on top, the temperature is on the order of 115F directly on the top of the fixture.
However, there don't seem to be any public specs about maximum temperature that a fixture can have to be OK for direct contact. It's really a bummer, because it means that, to be code compliant, I have to enclose the tops of these fixtures. Luckily, what seems to be a compliant way to enclose them is to build a box out of fire rated drywall, taped together with fire tape, and put it over the top. Yes, seriously. Taping a drywall box together and putting it over the top is compliant. Having a fixture that doesn't exceed 120F to begin with is not. I understand the needs for standardization in building codes, but that still left me with an incredulous look on my face.

So, just to be safe, I'll buy a sheet of 1hr fire rated drywall and build a 5" box around each of the fixtures. Does anyone have any more insight into fire codes, is there maybe something I've missed?