Witch and Cauldron Silhouettes with Coals

Introduction

We have a set of plywood bear silhouettes set up in our backyard for most of the year, visible from our house and from the street through the woods. This year, I decided to make a Halloween scene to replace them when they first go into hibernation for the fall and winter. The bears would be replaced with a witch and her cauldron, and there would be artificial lit coals under the cauldron.

The Silhouettes

To make the silhouettes, I first needed a pattern. I borrowed a nice outline for the witch

Baack silhouettes of a witch and a cauldron, drawn to scale with vertical and horizontal scaling lines.

Scale drawings of the witch and cauldron

that I found online, modifying it so that it would be easily recognizable, interesting, but within my personal jigsaw skills ability. The cauldron I just drew from scratch. I made scale drawings, with vertical and horizontal scaling lines marking what would be every six inches in the final build.

The purpose of the scaling lines was to make it much, much easier to freehand layout the full-size pattern on the plywood. I went from where each line in the outline crossed a scaling line to the next scaling line, hand-drawing in each segment. Once the pattern was drawn on the plywood at scale, I cut both the witch and the cauldron out using a jigsaw.

I primed the silhouettes with flat black spray primer / paint and then painted them with flat black barn paint.

Two images, one of the witch outline and one of the cauldron outline. Each is sketched onto a piece of plywood, along with scaling lines.

The outlines sketched onto the plywood, using the scaling lines.

Unpainted plywood silhouette of a witch, set on two sawhorses.

The cutout witch, prior to priming and painting.

The Coals

There are many tutorials online for making realistic looking coals using spray foam crack filler, spray paint, and orange string lights. Some, like what I built, are quite simple, while others are more involved, adding real sticks and ashes to make it appear more realistic. Since mine was intended to be viewed from a distance, I decided that there was no need for the added complexity.

A flattened oval black plywood base. On tope is roughly sprayed on crack filling foam, partly covering orange LED lights.

The fake coals, with the first of two layers of crack filling foam applied.

I cut a shape out of plywood with rounded short sides and straight longer sides, with a rectangular slot cut in the middle to fit the cauldron and support stakes. After painting it black, just as with the silhouettes, I cut a piece of scrap 2×4 to set over the slot, so that the crack filling foam wouldn’t expand into that area and block where the cauldron would go. I wrapped the 2×4 piece in a plastic garbage bag so that the foam wouldn’t stick to it. Next, I laid out the string of lights. I used a 100-light string of orange LED bulbs. You could probably get by with a 50-light string, but I liked having more lights. Some people use plastic cups or cut pieces of soda bottles to go around each light, but others don’t bother, and I didn’t. I figure there’s little heat coming from each bulb, so hopefully the string will last for years. I have heard of one person who used incandescent mini bulbs and a fire somehow started, so I’d stick to LED bulbs.

Once the lights are laid out around the platform, you just spray on the crack filler, keeping in mind that it will expand some. You want the lights partially or entirely covered to look more like hot coals. You can go a little light the first time, and then once the foam dries, add more where it’s needed.

Black plywood cauldron silhouette and fake hot coals (painted crack filler foam with embedded lights).

The finished cauldron and hot coals.

Next, I removed the 2×4 piece and used the same spray primer / paint to lightly go over the foam. The nice thing is you WANT the paint to be uneven, with some heavier, dark spots. Finally, I added some red spray paint highlights.

The last thing I needed was a spotlight to light up the silhouette at night. The coals show up clearly from the sidewalk and street, but the black silhouette is too dark without a light on it. I found a multi-color adjustable spotlight online that works great for this.

Final Results

The pictures here show the final result, from both sides in the daytime, and from the street at night, with the spotlight illuminating it.

Finished witch and cauldron silhouettes, with the cauldron on the fake hot coals. It is installed in a yard with trees in the background and leaves on the ground.

The installed project, viewed in the daytime from the back of our house.

The witch, cauldron, and "lit" coals (LED lights lit), seen at night. The silhouettes are lit by a spotlight.

The final project at night, as viewed from the street. The spotlight illuminates the silhouettes.

 

3d Printed Tiki Shades for Deck Lights

I like tiki / exotica music, visiting good tiki bars, and interesting tiki drinks. Recently, we were on vacation in Montreal and visited the Snowbird Tiki Bar. When we were there and looking at the decor, my wife suggested that I make some tiki covers for some of the lights on our deck. Challenge accepted!

Design

In order to build the tiki shades, I needed a 3d design. The basic concept began with a hollow cylinder with the tiki head design cut as holes in one side. I used TinkerCad to do the bulk of the design work. The shades had to fit around and over the deck lights, which are permanently attached to their cord, and the bulbs can’t be removed. So I needed the shades to be in two pieces that would fit around each light. I also needed a top with an opening large enough to let the cord through, but small enough so that the shade stayed on and didn’t simply fall down off the light. Finally, I needed a way to fasten the two halves of the cylinder together around each light.

A silhouette of a tiki face. It has a large nose, a large open mouth, and some other features.

The .png File for the Face

I first found a photograph online of a tiki light that I liked. From that I edited it a bit and the result was a mask as a .png file. The idea is to use the design to generate the set of holes to cut into the hollow cylinder, rather than try to hand-draw and cut out the holes. You can import a design such as this into TinkerCad and turn it into a 3D object provided it is in SVG format, not a jpeg or png. So I  used the free online SVGCreator to turn the png file into an svg. Then I simply imported the svg file into TinkerCad.

It took a couple of trial and error attempts to get the top the right size.

 

Closeup of a portion of the two cylinders. The left shows a small block attached to the inner wall with a square finger, while the right shows a small block with a cut out for the finger to fit into.

A Closeup of the Fastener Design, as Seen in TinkerCad

I probably could have reduced the failed attempts by measuring more carefully. To fasten the halves together, I first though of having a projecting shape on a small block on each side of one of the halves, and a matching cutout in a block on the inside of the other half. But I decided instead to use two fingers on one half, and matching slots on the other half. In hindsight, it might have been better to rotate the fasteners 90 degrees, so that the two halves didn’t get held in place against gravity just by friction, but it did work. If you make these yourself, the finger needs just a little bit of filing to fit snugly into the cutout and be held in place by friction.

A closeup of just the two fastener objects. The left has a cube with a square finger coming out one side, while the right is a cube with a cutout that the finger fits into.

A close-up photo of just the fastener objects. In the actual shades, they are integrated into the two shade halves and printed as one.

Printing and Building

The shades are printed upside down, so that the partially closed top forms the base for printing. Because of the large overhangs for the cutouts, there are a fair num

A photo of one of the shades in the 3d printer while it prints. A large number of tree supports are visible.

One of the Shades Being Printed.

ber of supports needed. I used tree supports, as shown in the figure. Once the shades were printed, I cut out diffusers from sheets of frosted plastic. These were bent and placed inside the shades and held in place with three small drops of hot glue on the top and upper sides.

The front halves of four printed tiki heads, each a different color, with cut plastic diffuser sheets in front of them.

Printed Tiki Shades and the Cut Plastic Diffusers that will go Inside.

Close-up of the two halves of a blue shade with the diffuser sheet that will be mounted inside. The fasteners are clearly visible inside the two halves.

Close-up of One of the Tiki Shades and the Diffuser Sheet.

The inside front half of a blue tiki shade showing the shade curved around and inserted.

The Inside Front Half of a Shade, with the Diffuser Ready to be Glued in Place

Front exterior view of a blue Tiki shade, with the diffuser glued in place.

Diffuser Glued in Place

 

Results

A view of the inside of the screened in deck, showing the eight tiki lights.

Set of Eight Finished and Installed

I’m quite happy with the results, and think that they look very nice, both in the daylight, when the different shade colors show up, and at night when they are lit. You can also print scaled down versions and put them over an LED candle. I did that with one of my test runs.

Blue tiki shade hung over one of the deck lights, with the light lit inside.

Finished and Installed Tiki Shade

Print Files

The print files for these shades are available on Thingiverse: https://www.thingiverse.com/thing:7154065

Crowd-Sourced List of Python Resources Related to Halloween

An AI-generated image. bats fly overhead, with a full moon visible. On the left is a laptop showing some computer code. In the middle is a pumpkin with the Python logo carved in it. There is also a black cat with green glowing eyes. If you look at this blog, you’ll quickly see that many of my projects relate to Halloween. I don’t know if this is a good, bad, or dumb idea, but as I was thinking about my use of Python for controlling Halloween props, I had the thought that it might be nice to have and share a crowdsourced list of python-related resources relating to Halloween, such as useful libraries (e.g., pyAudio, various libraries for using the GPIO pins on a Raspberry Pi), complete software packages (e.g., my own ChatterPi), or even Halloween-themed games written with Python. So, with some help from ChatGPT, I’ve put together a Google sheet, Python Resources for Halloween,  with some pre-populated content that anyone can view, along with a Google Form, Submit Python Resource for Halloween, where anyone can submit additional resources for inclusion.

The submissions are moderated, so they won’t show up immediately in the resource sheet. If you have anything to propose adding, please do so using the Google Form. If you have any other feedback, I welcome it as a comment on this post.