Exploration: Curved Fold Limits

(Materials: Bristol board; Designed on Illustrator, cut on the Zund cutter)

To see how I further developed this exploration, also check out my wearable sculpture:

Mountain and valley folds, the foundational folds of classic origami. With just a combination of the two folds, sheet material is transformed into all sorts of intricate, dimensional forms. What will happen if we introduce curved folds as a new fundamental? What new forms can be created from the ability to make folds with drastic direction changes? What are the tension limits for how steep a curve can be? If an origami design requires curved folds, how should we reinvent origami folding instructions to document them effectively?

With these curiosities in mind, I proceeded to prototype a range of curved folds — some flatter, some pointier, some with inflexion points — to study how paper behaves when folded along different curves (especially when adjacent to each other). Unlike straight folds that can be directly pressed down to secure, curved folds need to follow a scored path. This means that mountain and valley curved fold equivalents must be planned in advance and lightly cut on both sides of the paper, leaving little to no room for improvisation, introducing a bunch of potential alignment issues.

After lots of trial and error with hand scored mini experiments, I translated the curves that performed the best into an Illustrator drawing. The vector file was then sent to a Zund cutter, a computer controlled blade, to cut and score the design. One of the challenges was calibrating the machine so it would create a score path that is deep enough to release tension but shallow enough so it would not cut through the material or lead to too weak of a fold. This was quite challenging as the machine was not precise enough to make such small incremental changes, not to mention that the cutting bed was not entirely flat to begin with. Thus, even if the blade depth control was perfect, the paper could not lie flat and would as a result be cut at different depths too. For a first attempt at curved folds, this was quite a challenge!

Overall, the exploration was fruitful and helped me identify many essential areas for further investigation. I look forward to more paper studies and hope to eventually devise a system to test curved folds systematically. Since this exploration in 2017, Jun Mitani has published “Curved-Folding Origami Design” (2019). It is a must-read if you are interested in curved folding!