Week 7: On Painting with Big Things

Inspiration & Early Ideas

This week, I explored the idea of “painting with big things.” My initial inspirations included Louise Bourgeois’s spider sculptures, kinetic mobiles by Alexander Calder, and the playful scale of KC badminton installations. I wanted to build something large, sculptural, and functional— perhaps a huge planter, a modular chair, or even a sundial.

Ultimately, I decided to create something for the TPP lounge—something playful yet useful. I considered options like a big chess set, a low table, or a rocking chair to watch movies on. The idea of a rocking chair stood out for its balance of engineering challenge and comfort.

Designing the Chair

I began by researching various rocking chair designs for inspiration. My goal was to create a chair that could be CNC milled from plywood sheets, using interlocking pieces without the need for screws or glue. I sketched several concepts, focusing on modular designs that could be easily assembled and disassembled.

Circular cutout chair design sketch — Cutout Chair Design Inspiration

Modular interlocking chair design concept — Modular Chair Design Inspiration

Laser-cut plywood chair concept — Laser-cut Chair Design Inspiration

Alternate laser-cut chair design — Alternate Laser-cut Chair Inspiration

I was inspired by the oval rocking chair design by Andrew Doxtater, who provides a rounded construction kit online. I recreated the oval form from scratch in Fusion 360, adding cutouts for the seat and backrest, and later experimented with armrests. To strengthen the structure—since OSB isn’t particularly strong—I added reinforcements to the bottom and backrest.

Reference image of winning rocking chair design — Winning Rocking Chair Design Reference

Fusion 360 Chair Design – Initial Shape

Learning to Mill

Once my design was complete, I moved on to CNC milling. I began with calibration tests— making a comb joint to check material tolerances. Many thanks to Geoffrey, our amazing monitor, and Chris, the woodshop manager, for their guidance and endless woodworking insight.

Comb joint test cut for slot fit — Comb to Test Fit

Loose comb showing oversized slots — Example of an Oversized Fit

Properly fitting comb joint test — Example of a Good Fit

Measuring plywood stock dimensions — Measuring the Stock

Since the design was parametric, I easily adjusted the slot size in Fusion and exported the DXF for milling. Chris helped me adapt it for Mastercam, which the architecture machines use. I also learned about using “trees” to support small pieces during milling.

Notes on cutting small parts using tree supports — Design Notes for Milling Small Parts

CNC milling setup screen in the lab — Milling Setup on the Computer

CNC milling machine in the shop before operation — Milling Machine Ready to Start

CNC milling process cutting plywood sheet — Milling in Progress

Milling Process Video

After milling, I snapped the parts out of the onion skin and used a router to round the edges.

All milled plywood chair parts laid out on the table — All Milled Parts After Router Clean-Up

Assembly & Adjustments

First step in assembling the rocking chair — Assembly Step 1

Chair assembly showing mismatched bottom slot — Assembly with Incorrect Slot Size

Here’s where problems began—the bottom piece didn’t fit properly. I realized I had parametrized one of the slots incorrectly, making it too small. The chair rocked, but slightly off-balance.

Rocking on the First Chair

With some help from Gert and Chris, I tried fixing it using a hammer. Unfortunately, OSB isn’t very sturdy—and this approach caused more damage than progress.

Damaged OSB chair parts after hammer adjustments — Destruction by Hammer

Eventually, we cut out the damaged part and milled a corrected replacement. The new version worked perfectly!

Completed rocking chair in OSB after reassembly — Final Chair

Finishing Touches

I wanted to personalize the chair by adding text inspired by my mom’s favorite song, “Dance Little Sister” by Terence Trent D’Arby. Unfortunately, I couldn’t get the laser cutter to cooperate, and the transfer paper didn’t work as expected.

Typography mockup planned for the side of the chair — Planned Sticker Design

Failed vinyl transfer paper test for lettering — Failed Transfer Paper Test

In the end, I decided to leave the chair as-is. It’s charming, imperfect, and comfortable—especially with pillows.

Finished rocking chair with pillows placed for comfort — Chair with Pillows

Happy Rocking on the Chair!