December 2023 Pop-Ups

Three cards for December!

Ideas

As usual, November is a busy time for making the three December pop-ups: the regular December card, a birthday card, and Christmas cards.

The Sierpiński triangle has been on my list of ideas for a while, and I finally used it for the December card, aka as Study in Black and White VI. Initially, I thought this may be too much like the Study in Black and White IV card, which used a four-sided pyramid, but this is a three-sided pyramid, or tetrahedron.

The shape caught captured interest over 30 years ago when I saw it on a Nova episode on Chaos broadcast in 1989. Here’s a copy of the episode and the first few minutes shows the triangle. To prove to myself what the video showed, that night I wrote a program to do the same thing and was amazed. Over the years, I have recreated the program in several languages and my web version of it is here. By pressing the Plot buttons a few times, you will see the image emerge.

For the birthday card, the mice helped out again. Since Mom Wardinkle is 83 this year and 8 and 3 have similar shapes, I thought I’d use that as the central mechanism for the card.

I tried to find a new Christmas-related topic I haven’t used yet and landed on the nutcracker.

Designs

December Card

Study in Black and White VI

back of birthday card December card

The Sierpiński triangle has triangles that get infinitely smaller and the triangles connect at a point, which would be impossible as a 3D paper model. Doing sketches for this card, I found that three levels deep was satisfactory, and practical. Instead of connecting at a point, I created a 2mm line between the triangles to connect them.

In my final, full-size sketch I made pyramids of each triangle, which created a total of 13 pyramids: 1 full size, 3 half size, 9 quarter size. Below is a photo of the mechanism ready to assemble with all the folds scored. The white pieces of paper will be the joints between the pyramids.

dec sketch December sketches

It worked ok, but making it fold flat proved problematic. First, with many layers across the base, it made the folded card awkwardly thick. The second and more serious issue was the stress on all the 2mm connections that had to fold were too weak and tended to tear. I tried enforcing that area, but that didn’t help. I ended up cutting out all the interior pyramids and that worked well. The next photo shows all of the sketches. In the lower right of the larger, green one you can see a remaining flap from interior pyramids that I cut out.

dec sketch December sketch

I created a pattern for the base and mechanism and printed them on Bristol, as I have done with all the other Studies in Black and White. As usual, the black isn’t very dark but matches the other cards in the series. Then I cut the mechanism out by hand. and assembled it.

dec lined up If you line it up, it almost disappears

Birthday Card

The animation at the top of this page shows the 2023 birthday card design.

Since 8 and 3 are essentially stacked circles I thought I’d have them overlap, then reveal 83 when opened. To do this I used a flap mechanism that when pulled, flips over the 3 to reveal 83. Of course, the mice had to get in on the action by pulling the flap. To add more movement, the pull tab also pulls a line of mice near the front of the card and an airplane with a banner flying over the trees.

This pull tab is one of the simpler ones I have done since all three moving pieces move with the tab. There are no levers or arms that move in other directions. Below is the back of the card before it was covered up. The moving part is outlined in green.

back of birthday card Back of card with pull tab mechanism

The base colors are from Michael’s cardstock, and the illustrations were done with PrismaColor pencils and Pitt Artist Pens. For the “present” I used some patterned paper. The flap that pulled it was blue, so I thought I’d be clever and put a matching piece of paper over that area, but just that thickness of paper stopped the flap dead when it tried to slide into the slot. I had to redo the flap, and then color it white to somewhat match the paper.

Why blue and yellow? I don’t know. When I made the sketch for this card I grabbed blue and yellow and it looked nice, so I stuck with it.

Everything was cut by hand aside from the numbers, which were cut by the machine.

Christmas Card

Ready to march out

I tried different mechanisms for the nutcracker but decided to use a simple parallel fold to make a standing figure as the card was opened. This is very similar to the 2016 Christmas card below.

2016 xmas 2016 Christmas

The 2016 card had no printing or coloring. For the nutcracker, I thought about using a similar method, but for the front alone, it would have taken over twenty separate pieces. Instead, I decided to use the Silhouette Cameo’s print-and-cut feature, which allowed me to use more colors and patterns. The cutting worked ok, but was consistently slightly off to the right (even though when running the calibration it was spot on). You may notice a bit more white on one side versus the other.

nutcracker-front nutcracker-back Front and back of the nutcracker

Designing the front and back of the nutcracker for printing did take a while, but assembly was very easy. Like the 2016 card, there’s a flap at the top that hides “Merry Christmas” and our signatures.