Chandelier Saga Part 2: CAD

Chandelier Saga Part 2: CAD

Picking up the story of making this giant lamp, we get to the hardest, most important part, but also the least photogenic. That would be, the computer modeling and prototyping.

Here's what I was going for in terms of structure:

The scales are made of 1/16" thick plywood, linked to their neighbors by bolts. The struts spanning the widths of the scales are there to pull the ends together and make sure the centers bend upwards to let enough light through.

It turned out to take something like 4 full rebuilds of the computer model before I was happy with it. The root of the problem is related to the fact that it's really hard to model how real-life materials will bend. So every few days for a couple weeks I had to re-draw all the geometry with slight differences, head in to the laser shop to cut the pieces out, and assemble them to see what it would look like.

Hit the jump for a bunch of screen shots of the different steps involved in designing the final piece.

Working in Rhino (my 3D Computer Aided Design software of choice/training/convenience), I started with an ideal originator surface, created by revolving a curve. I dropped grid points along it:

Then I drew out the base shape for the scales with points and lines. The tips of the scales are drawn out in space perpendicular to the grid point they're above. Their distance from the surface is proportional to the width of that scale:

Next, turning that into surfaces and mirroring the scales along their center-line. (Also, there were some steps involved in expanding the edges of the scales to accommodate the bolts.)

Next comes a polar array to get them all in place:

And a cut-away view to show the internal structure that would hold the light bulbs in place:

But then (after testing the floppiness of the previous prototype) I decided I should give it a bit more structure to support certain points of the surface. Figuring out the geometry for that was a pain:

With that done, time to flatten the scales:

...and lay out the sheets that I would be laser-cutting:

Then I just have to cut twelve copies of each of these sheets, plus a half dozen or so more sheets for the internal structure.

And that mostly wraps it up for the CAD part of this story. I'm intentionally glossing over a lot of the geometry headaches, because you don't want to think about it. Trust me.

Next up will be photos of construction! Though I foolishly forgot to take any photos of actually laser-cutting the scales.

I'll leave you with the front view of that prototype I showed at the beginning:

Here are progress shots of a leather helm I just finished up. Another post with photos of it finished will follow.

I did the designing in Rhino, which is a 3D modeling program I've been using ever since architecture school. It was unexpectedly frustrating to find a 3D scan of a head, but I finally found one on Thingiverse with a creative commons license, which I am grateful for. I really wanted to get the geometry for a head right, that was the whole point.

To be honest, this particular design I was thinking of mostly as a test or proof of concept. I'm planning on making more in a similar manner, and I figure I'll work on more compelling shaping and detailing for those, but I wanted to just make a smooth one first to make sure it worked. I didn't want it to be completely plain, though, so once I'd gotten it cut I punched holes for purposes of putting spikes through.

Then I had the question of what color to do. I figured I could just do a plain black, and with all the spikes it would be extravagant but not out of genre for punk/goth/industrial or something. But I wasn't super excited about that, and I realized that there were 6 sections, and after some agreeing suggestions from a friend, I decided to go for a huge rainbow. Which means it's completely ridiculous, and a good contender for the most outlandish piece I've made to date.

For future versions, I think I'll try with thicker leather. I also figure I'll do some toying with making the pieces fold/bend like spiky scales or something, which would give me something more in keeping with many other of my designs. And maybe also some different patterns of breaking up the surface into panels. And definitely riveting the pieces together, that would be much faster.

Anyway, next up will be photos of the final piece. But not now, tomorrow. It's time for bed.

I went out with a friend and got some photos of a bunch of the leather bracelets that I'd neglected getting photos of for a while! I won't link to these individually, but all these designs are up on my Etsy shop.

This dragon tail is made of white painted aluminum, a material I hadn't had much chance to experiment with before. It claims to be a sturdy automotive paint, and it definitely has a storm trooper sort of feel to it. Personally, I'd been a bit hesitant to make much with it, because I don't really trust paint on metal, but it seems durable enough, and I sent some sample scales to the commissioner and she was cool with them.

The tail is a pretty short one, at only 24 inches long. It's also got a line of spikes down the spine.

If you're curious about these tails I make, check out this page with information about them: http://armoreddragon.tumblr.com/tails

Finally took video of a dragon tail being swung. It's quick and not perfect, but it exists! Next time I'll try to figure out why it didn't record audio, and also I'll have a tripod.

Because chainmail isn't rigid, these tails swing very smoothly. Fluid, sinuous, curling and extending as gravity and inertia dance with each other. So much better than a fabric tail with stuffing.

Also, a milestone to note: This page just passed 256 followers! That's 2^8 people. And that's awesome. Thank you all. I'm happy to be able to make things that you enjoy.

Cranked out these two dragon tails over the span of a week! It felt good.

The rainbow one I made for myself, and managed to get it done before Halloween. Someone had purchased my previous personal tail shortly before, and I needed something to show off for the holiday of costumes. I'd had the rainbow tail idea kicking around in my head for quite some time, and I'm happy I finally got it made.

The black and red one was made for a commissioner.

Both are made of anodized aluminum scales linked together with stainless steel rings. Both also have lobster clips at the tip for attaching a spade tip to. I'll be cutting the leather for the commissioner's spade tip tomorrow. For my own, I usually cut a few different ones out of different materials to swap out whenever I feel. Also, whenever I find myself at an appropriate party I'll clip glowsticks onto them.

If you're interested in these tails I make, you can check out my tail information page! I'm finally catching up on my commission queue, so I'm likely to finally be able to get new commissions done with relative speed.

I'm thinking about putting a whole lot of metal spikes into the rainbow tail, so it'll match the crazy rainbow helm I recently made. But it'll have to wait until I order more spikes, because that helm used up all of the spikes I had of those types.