A while back, I spent time with some friends, playing board games outside by candlelight. It was the afternoon and getting dark. Someone brought out a candle with three wicks, and someone else in the group absolutely lost their mind at the sight of it.
“What is that!? That’s the biggest candle ever! How is such a thing allowed to exist!? Has human technology really come this far!?”
– Ian
The reaction was a bit much. And it was bizarre in that it wasn’t really that big of a candle. Whether he was just in the mood for hyperbole, or we were all really drunk, or C – all the above, none of that mattered. All that mattered now was the new mission: to make an even bigger candle and put that other one in its place!
The Concept
In theory, making a candle is pretty simple. You get a big clump of wax and thread a wick through it. And you’re done! That’s perhaps an oversimplification, but still the basic premise.
I could find a big bucket and quickly dump molten wax into it, but that’s the easy way out. So I decided to attempt something slightly more ornamental. But the manufacturing still had to be sane, or else all this nonsense would become too big in scope, and we’d never get a final product. The main things that were decided were:
- Multiple colors
- Distinctive (interesting) shapes
- Pretty large
The distinctive shapes and multiple colors meant we’d have multiple pieces, which would need to be cast, which means a mold. The first thought is to FDM print the molds, but FDM filament can glass transition (i.e., distort and turn wobbly) since it would be dealing with hot wax. I would also be limited by print bed size and need to deal with print times. It could be possible, but let’s keep mulling over ideas. Some kind of silicone casting? No, that idea felt awkward – especially at scale with my limited abilities. So what material and method would be suitable and scalable?
The Molds
I talked to a friend about potential designs, and he suggested a rune pattern and sent me an image of Dagaz. Because the person we’re giving this to is into runes, symbols, and pseudo-mystical stuff. After looking at it, it occurred to me that I could make that into an extruded shape. I could make it large if I design it as a simple paperboard model – and I could make it rigid and create a liquid barrier with it if I coated it in resin. That process wouldn’t be as hands-off (more labor intensive) as 3D printing, but I could still digitally design it and involve a machining process (via Glowforge) to do some precision work.
Digital Assets
The pattern was designed in Blender. I needed to make sure to keep the poly count down so that assembling it as a paper model would be a sane process. The models and their unfolded meshes are shown below.
Tip: Turn on viewing wireframe in the Sketchfab app’s Model Inspector.
From there, the unfolded parts were exported as a flattened mesh and converted to an SVG.
The SVG was then processed in Inkscape so that the outlines of entire forms were respected, and fold lines were partially burned into the cardboard as guides. From there, the designs were scaled to the appropriate dimensions and prepared for the Glowforge to laser cut.
Construction
There were three main parts:
- The exterior of the entire candle. (x1)
- The exterior of the extruded rune. (x1)
- The hollow insides of the rune. (x2)
The mold for each piece came in two parts that formed a clamshell. This was done so the parts could easily be released. This means altogether, eight chipboard models made up the mold assembly.
The parts were folded, glued at the seams with superglue, and infiltrated with epoxy resin. The clamshell pieces were stuck together with green frog tape.
There was also a bottom plate made with landmarks for where the bottom of the wicks should be anchored to. Along with that was a laser-cut Birch plywood structure to hold the wicks upward while casting.
Casting
Wax Details
This project was done years ago, and I can’t remember the wax used. It was either Parrafin wax, Soy wax, or a mixture.
I still have the candle wax and supplies still sitting around in storage. I should probably use them up, making regular candles, and give them out to clear the storage space.
The picture of the rune from the website was red, so I left it red. When it came time to decide on how to scent the handle parts, the red parts would be strawberry, and the white parts would be vanilla.
All the supplies were purchased at Hobby Lobby. This also includes the scents and the candle color dye. Their candle isle doesn’t play games.
Unintuitively Thin
We’re all familiar with melted candle wax; it’s gloopy and thick. I was expecting if the molds had any small leaks, the wax would be thick enough to plug those areas. What I did not know is that candle wax can be CRAZY thin when hot enough.
Who knew?
It basically had the consistency of water. A really runny liquid. This means if my chipboard molds aren’t watertight, they will spring links.
Spoiler alert, they were leaky.
Regardless of exactly why this thing has leaks, the issue with the really thin wax came as a surprise. Because I had no idea, I didn’t take any precautions when constructing the molds. And tracking down exactly where that’s coming from and how to resolve it could be a pain.
Ice Bucket
If I thought the wax was going to be thick enough to clog itself, maybe that’s still the case if it wasn’t so hot. So I heated the next batch of wax for less time and casted parts in a bucket of ice. Hopefully, the wax that leaked outwards would cool and clog the leaks from the outside. And yes, this did the trick.
After getting a few successful things to cast, I realized the use of ice and lower pouring temperatures were necessary anyways. The large amount of liquid wax takes a long time to solidify and reharden – lowering those temperatures helped speed the process.
The Delivery
In Microsoft word, I make an invisible table that takes up the entire width and split the table in half. I then copy it to a second page and use that as a template to design a double-sided card. Throw in some text to add explanations, some to add spite involving its grandiose number of wicks, and some to add yuletide cheer.
I box it up and hand it over at the Christmas party that happens every year. It’s heavy enough that I need to remind everyone that it’s shown to, to hold the box from the bottom so it doesn’t break through.
The candle probably ends up being about 20 pounds of wax. In hindsight, I probably should have weighed the final candle, measured it, and taken some pictures of it. Although, he was kind enough to send me some pictures of it later.
He used it for a while, but the wicks eventually got finicky. I think at a certain point, too much liquid wax was pooling and drowning some of the wicks.
In the end, the candle was built using a process I threw together for a gag. It worked well enough, and no one’s house was burned to the ground; I’ll consider it a success.