An invitation went out on Fakebook to join a “fold along” session with Fergus Currie and, although it was after 11pm local time I thought why not:

Fergus taught the module then construction of a 4-part modular Frustum (a truncated pyramid) – an ingenius and “frustrating” model in that the lock between modules is accomplished using a “latch crimp” tab inside the bent gusset pocket, making the actual construction a little fiddly.

I found I needed to ease the 3rd and 4th modules in place using long-nosed tweezers, when it sits right it locks tight but requires a bit of a controlled jiggle to get it to be seated just right. The final module is a bit of a challenge to insert without dislocating the two either side of it.

Patience and tweezers finally won over and the top half finally was locked tight and tidy, then a simple weave on the bottom flaps complete a lovely truncated pyramid. Material thickness is an issue here – the tab-pocket system assumes material of negligible thickness. If you use heavier paper you need to fractionally adjust either the pocket depth or the tab length – fortunately there are a couple of fold junctures that make this easier.

I can see many uses for this – particularly if folded in monocolour – it would be a good base for another origami. It is unusual, I have not seen a geometric form folded like this one before and, as usual, Fergus’s modules originate from squares and are really tidy – a module completes an entire face, with deep positive pockets and one kinked tab that hooks around a gusset inside the pocket. Nice simple landmarks, you can see the basis of the face almost immediately which helps in orienting the tab/pocket and hiding all the other paper away.

It was nice to be among some absolute legends in the class (Brill and Bascetta), the pace was good and the video record makes going back over the landmarks easy. Thanks Fergus for the opportunity.