🥧The Pi(e) Equation: a Pi-Pie Inspired Chocolate Gift 🥧

I wanted to bring together my love for design, modeling, crafting, and sweets into one delightful surprise: a jar topped with a realistic mini pie that hides math-inspired chocolates 🧁➕🔢

The result? A playful fusion of art, baking aesthetics, and math geekery — perfect for Pi Day, a nerdy gift, or simply to celebrate creativity.

Follow each step carefully to create your own punny pie filled with symbolism (and chocolate)!

1. 1 round jar with a twist-off lid
2. Modeling clay
3. Small drill or rotary tool
4. Thin wire
5. Acrylic paints (red, reddish-violet, sandy beige, white, brown, black)
6. UV resin and UV lamp
7. Glitter or mica powder (optional, for the shiny filling look)
8. Silicon brushes and/or clay modeling tools
9. Autodesk Inventor (or any 3D modeling software)
10. 3D printer
11. Mold-making silicone
12. Disposable cup
13. Small screwdriver
14. Chocolate and white chocolate for melting
15. Water
16. Small pot and bowl for double boiling
17. Refrigerator

I used a round jar with a twist-off lid — the circular shape felt perfect for a pi-inspired pie!

I drilled six small holes into the lid using a rotary tool and a fine drill bit. The holes were arranged in three pairs, spaced evenly near the edge.

I then inserted small pieces of wire into each pair of holes, twisted them a few times, and left the ends sticking out. These wires will hold the pie topper firmly in place later on.

I kneaded some modeling clay and pressed it onto the lid, creating a rough, bumpy surface to mimic the texture of a real pie.

Using a clay-sculpting tool, I added more defined details to enhance the rustic, homemade look.

Once the clay had dried completely, I painted the entire surface with red and reddish-violet acrylic paints. This creates the base for a juicy fruit filling look.

After the paint dried, I mixed UV resin with a bit of shiny powder pigment and gently spread it over the top.

I then cured the resin under a UV lamp. This gives the filling a glossy, fruity sauce-like effect that catches the light beautifully. 🍓

Using Autodesk Inventor, I designed a cookie cutter in the shape of the Pi symbol (π).

To do this, I pasted the Pi character into the “text” feature and tried different fonts until I found one I liked.

I extruded the symbol, hollowed it out from both the top and bottom, leaving 0.4 mm walls (to match my 3D printer nozzle size), and added a grip around the edges.

I exported the file as an STL and 3D printed my Pi-shaped cutter.

To create a more accurate and reusable edge for the pie, I designed a second cutter with a curved, wavy border using Inventor.

While this part could be cut manually, I preferred the precision (and reusability) of a custom cutter.

I also created a circular cutter to define the inner edge of the border of the pie.

I rolled out more modeling clay and cut thin strips — almost like little pasta ribbons.

Then I wove them together just like a traditional pie crust lattice.

I placed the circular cutter over the woven lattice, not to cut directly, but to mark the area.

Using a clay tool, I carefully cut around that circle.

I used the Pi cutter to cut out a symbol from the center-top area of the lattice.

Then I placed the woven crust with the Pi cutout onto the jar lid — now painted and coated in glossy resin.

I added small bits of modeling clay beneath the Pi shape and smoothed them out with a silicone brush and a little water.

I flattened more modeling clay and cut a circular piece for the base.

I placed it over the lid and used a clay tool to gently texture the outer edge, simulating a pie crust border.

Using the wavy-edge cutter I designed earlier, I trimmed the border.

To add a cute face to the pie, I created two small holes for eyes and used a bent paperclip to carefully press in a simple smile. 😊

I added more texture to the border using a modeling tool, giving the crust extra dimension and a more baked look.

Once the clay was fully dry, I painted the entire surface using a sandy beige color mixed with a bit of white.

This gave it a soft, pastry-like appearance.

Using a sponge with very little paint, I dabbed sandy beige over the top of the pie crust.

Then I added a touch of brown in the same way to give it a toasty, baked finish.

I made two small balls of modeling clay for the eyes, placed them into the holes created earlier, and painted them black, same for the smile.

In Inventor, I created 3D designs for chocolates in fun math-inspired shapes: the Pi symbol, the digits of Pi, circles, and an infinity sign.

I extruded them and added open-box outlines around them to use as mold frames.

I exported the mold files as STL and printed them in 3D.

I filled the printed mold with water and poured it into a disposable cup.

I marked the water level on the cup, then dried both the mold and the cup completely.

I made a second mark at the halfway point between the bottom of the cup and the water line.

Then I poured silicone part A up to the first mark, and silicone part B up to the second mark.

(Note: The ratios may vary depending on the brand of silicone used, always follow your supplier's instructions!)

The next day, once fully cured, I removed the silicone mold. I gently loosened the edges using a small flathead screwdriver, then pulled it out by hand.

I melted chocolate in a double boiler and poured it into the silicone mold.

After 15 minutes in the fridge, I repeated the process with more chocolate — this time including white chocolate too.

Once everything is dry and set, place your chocolates inside the jar and screw on the pie lid.

Now you’ve got the perfect Pi(e) Day surprise — a geeky, sweet gift with a clever twist.