3D Printing 13 Bowls

… or maybe 12, or maybe 14; perhaps even 15. We’ll get to that.

I have in mind one or more blog posts on my personal trials and tribulations with 3D printing. This is not that post. Here I’m focused on one particular task: printing the Acorn Garden libation bowl.

Truth in advertising: The various pictures and videos below are not presented in chronological order, so that I can make the narrative more exciting (…for some value of the words “more” and “exciting”).

Why I did it

Acorn Garden is the name of my Wiccan Grove. I’ve run this teaching group since 1999, building up a collection of various rituals tools along the way.

One of those ritual tools is a “libation bowl.” During a typical Wiccan ritual, there’s a section called “Cakes and Wine” (C&W). As the name implies, we drink a consecrated beverage (not necessarily wine) and eat consecrated food (not necessarily cakes). Although this sounds superficially similar to Communion, it does not serve the same purpose; it’s more like sharing a feast with the Gods, who are our honored guests.

One of the principles of sharing this feast is that the Gods get the first sip from every bottle, the first sip from every cup, and the first bite of every food. This is called “libation.”

We give the C&W to the Gods by offering it to the earth. If we’re worshiping outdoors, we just pour a bit of the liquid on the ground and toss a bit of the food outside our Circle.

If we’re conducting our ritual indoors, it’s not practical to dribble C&W on the living-room carpet. So we put the libations into a bowl, called (remember this; this will be on the test) a “libation bowl.” After the ritual is over, someone (typically the High Priest) will take the bowl outside and spill its contents onto the ground.

In and of itself, there’s nothing special or magical about the libation bowl. Pretty much any bowl will do.

One of the bowls I used to use as a libation bowl, before I embarked on the adventures described in this blog post. Note the lack of a glowing aura of radiance. If you were to drink from it, you would neither be healed nor age into a skeleton; sorry.

It was Deborah Lipp who pointed out to the general Wiccan community: If you put both liquids and soft foods (bread, cake, cookies) in the bowl, the food will swell up and look yucky. The solution is simple: Use a divided bowl with separate compartments for liquids and solids.

I would occasionally search for a two-compartment libation bowl to replace the one in the above picture. All the ones I found were chips-and-dip bowls intended for Superbowl parties. It wasn’t a big deal for me, but the notion stayed in the back of my mind.

Tangent: The Acorn Garden logo

In the mid-2000s, the artist and performer Melissa Arleth sent me a postcard with a bit of art that reflected the name “Acorn Garden”:

Original Acorn Garden painting
Artwork by Melissa Arleth of Cirque du Sewer

A few years later, I decided that I wanted a logo for my group. I asked my friend Vann to design one based on Melissa’s artwork. He came up with this:

Acorn Garden logo
Artwork by Vann Godfrey (link possibly NSFW)

I had this logo turned into a tattoo on my left shoulder, and had it printed on cards and pens and t-shirts and shopping bags. It was a fun way to link members of the group.

Enter Shapeways

As I described in an earlier blog post, in 2013 I started to design and print jewelry using a 3D-printing service, Shapeways. I even created a couple of necklace designs using the Acorn Garden logo, though I did not put them up for sale to the general public:

At some point, I realized: If I couldn’t find the libation bowl I wanted for sale, why not design my own and have Shapeways print it for me? I talked about this in an old post, but to spare you a couple of mouse clicks:

The original Acorn Garden libation bowl design, created using Cheetah3D.

I derived it by taking the middle acorn in the logo, cutting it in half, and fiddling with the boundaries a bit to create walls suitable for libating C&W. Here is the result that I received from Shapeways:

Acorn Garden libation bowl in ceramic
The Acorn Garden libation bowl, as printed in ceramic with pale yellow glaze, by Shapeways.

It was pricey (about $130), but I thought the results were worth it. We used it in Acorn Garden, and indeed still use it to this day.

Fast-forward another few years. It occurred to me that all it would take is a moment of clumsiness for that libation bowl to drop and shatter. It wasn’t the most precious magical tool I owned, but I’d miss it if it were gone. I decided to make another one, just in case.

Then I learned that Shapeways was no longer printing in ceramic.

By coincidence, a year or so ago I met the person who was responsible for ceramic printing at Shapeways back then. She told me that once she left the company, Shapeways no longer had the expertise nor the interest in keeping up with printing in ceramic.

I investigated other 3D printing services. No one else was printing in ceramic either.

Doing it myself

In 2020, I purchased my own 3D printer. At some point, I realized that I could print my own copies of the libation bowl.

To be sure, I could have had Shapeways print the bowl in plastic. However, it cost more to print in plastic than in ceramic for a given volume. As of July 2022, Shapeways charges over $200 to print this bowl in their least expensive plastic. They offer other materials, but I wasn’t going to pay over $3000 to print the bowl in steel.

Also, as we’ll see below, if I printed them myself, even though I’d have to print in plastic, I’d have complete control over which filament I used. I could print in different colors and textures:

This is what 3D printer filament looks like. I printed the spool hangers using rainbow filament (3rd spool from the left). You can see the color transitions as I successively printed the hangers from the same spool.

All of the filament you see here is PLA, which is short for Polylactic Acid, a kind of plastic that is “more” environmentally friendly than most other kinds. I put “more” in quotes because it means that PLA will biodegrade in mere centuries where other plastics take millennia.

I decided to modify the design a bit, to include the Acorn Garden logo as an engraving:

The engraved Acorn Garden bowl, as designed in Cheetah3D.

I started printing:

Failures

The Acorn Garden libation bowl was the most ambitious 3D-printing project I’d attempted up to that point. I had my share of failures, and even after some successes I still had problems:

Sometimes the print went wonky. About a year after I tried this print, I learned that pushing the limits of silk-textured PLA filament is not a good idea.
This is what happens when you have a power outage 20 hours into a 24-hour print job. Some 3D printers can recover after a momentary power outage, but my setup cannot.

The “grid” pattern you can see within the walls of the bowl is called “infill.” There’s usually no point in printing plastic that will never been seen, so in 3D printing we use infill to hold up the outer walls instead of wasting plastic to print a solid object.

Here’s a 14-minute video in which I (a) show off my cats, (b) show how 3D printing works, (c) show a failed bowl print, and (d) am totally wrong about the causes of the print failure.

From the ashes of disaster come the roses of success

Finally, I succeeded!

Here’s a time lapse of a successful print. Even though the video is only 13 seconds long, consider the “Elapsed” numbers in the upper left-hand corner. The time-lapse consists of one frame per layer, 30 frames per second, for 15-hour print job. As I later (re-)learned, I probably would have gotten better results if I printed more slowly. (If you look carefully in the first frame of the video, you’ll see Jiku lounging in the upper right-hand corner of the image.)

The Acorn Garden libation bowl printed in brown silk filament. This was my first fully successful print of this design. It took about 24 hours to print.
The second Acorn Garden libation bowl I printed, in green PLA filament.

How much success do I need?

A question has probably already occurred to you: Originally, I was only looking for a single spare libation bowl. Why did I start printing more?

Mainly because I could. There were many interesting colors and textures available, and I wanted to see how the bowls would look:

Nine Acorn Garden libation bowls, printed using different PLA filaments. Clockwise from 1 o’clock: brown silk, rainbow, rainbow again, brown filament again, blue silk, silver, black, green; rainbow again in the center.

The reason why the rainbow bowls look different is that I printed them at different “cycles” of the color changes along the length of the filament.

Also, they had become a nice decoration for my apartment:

I used a free 3D design website, Tinkercad, to create a wall bowl hanger. It’s based on a bowl hanger I found on Amazon. The colors you see here are assigned by Tinkercad, and have nothing to do with the color of the plastic I used to print the hangers.
How an Acorn Garden libation bowl looks in one of my 3D-printed hangers. It held a bowl well enough, except when a cat decided to jump on top of the bowl on the way to higher ground, so metal hangers were still necessary.

I cheat

In the above pictures, you can see nine bowls. I’ll confess, I cheated: I also had a bowl printed by an outside printing service.

Wood AG Bowl
The Acorn Garden libation bowl printed in wood filament

The reasons why I cheated:

  • I wanted to see how a professional service compared to what I could do.
  • I wanted to print a bowl using wood filament. Printing using a filament embedded with abrasive particles (e.g., wood; metal) is hard on a 3D printer’s nozzle. I selfishly chose to have their nozzles potentially ruined instead of mine.

You can probably see that the professionally-printed bowl is not much different from what I made. Also, despite it being called “wood filament,” the result does not particularly look or feel like wood.

Dual-color filament

For about a year, I was content with ten libation bowls hanging on my wall. Then a company came out with dual-colored filament. This is not the same as the rainbow filament you see above; that filament is manufactured with color changes along its length. Dual-color filament is manufactured in process similar to that of striped toothpaste.

The net effect is that dual-color filament looks different depending on which side you look at. In the following two photos, I’m holding the same spool of filament; all I did was flip it so you could see both sides (and both cats):

Matterhackers Quantum purple-gold filament, seen from the gold side. You can see my cat Jiku inspecting the other Quantum filament spools.
Matterhackers Quantum purple-gold filament, seen from the purple side. You can see my cat Shuba wondering why I’m paying more attention to plastic filament than to him.

I had to give this a try. It worked, though I’d forgotten some of the techniques involved in printing large items in silk-like filament. A simple picture can’t show the color changes, so here are three videos.

Purple-and-gold filament (the white stuff in the bowl is drying polycrylic; see below):

Green-and-white filament:

Rose-and-yellow filament:

That adds three bowls to the ten pictured above, for a total of 13… or only 12, if you don’t want to include the “cheating” wood-filament bowl. Or perhaps 14 if you include the original ceramic bowl.

Safety

By far the mostly likely fate of these bowls is to hang as wall decorations indefinitely.

But what if they were to be used? Or what if, in a ritual, we needed additional bowls for some reason?

I had to deal with the reality that PLA plastic is not food-safe. To be sure, I don’t plan to eat any of the food or beverage that’s placed in the bowls, but I can’t be sure that will be true forever.

Also, the 3D printed bowls are not water tight. There are enough gaps between the layers of plastic filament for liquid to seep through. Where you have liquid, you can have bacteria, trapped within those grid-like crevices you can see in one of the pictures above. The whole thing can become a hazard.

So I coated the inside of each bowl with six layers of polycrylic. I used the liquid form on the inside, and a spray version for the outside.

Thirteen Acorn Garden libation bowls are held onto foam core with poster putty. The boards are lying in my parking lot, waiting for another application of polyacrylic spray.

Are we done yet?

Maybe not!

I recently purchased some additional filament for printing miniature figures and some household items. One of the spools is copper silk PLA. I’ll do my usual test prints with that filament. If it looks like it might make a neat bowl that doesn’t look like what I’ve already got, I’ll probably go for it.

So I might have 15! And if more exotic filaments come out, who knows?

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