The Magis Spun chair is a weird piece. It’s basically a kind of seat with a round conical base that stops it from sitting still in one place. Instead, it rolls and pivots around when you sit on it, which is apparently quite fun. They’re expensive though, which gave [Morley Kert] a neat idea. Why not 3D print one instead?

Obviously 3D printing a sofa wouldn’t be straightforward, but the Magis Spun is pretty much just a hunk of plastic anyway. The real thing is made with rotational molding. [Morley] suspected he could make one for less than the retail price with 3D printing.

With no leads on a big printer, he decided to go with a segmented design. He whipped up his basic 3D model through screenshots from the manufacturer’s website and measurements of a display model in a store. After print farming the production, the assembly task was the next big challenge. If you’re interested in doing big prints with small printers, this video is a great way to explore the perils of this idea.

Ultimately, if you want to print one of these yourself, it’s a big undertaking. It took 30-50 print days, or around 5 days spread across 15 printers at Slant 3D’s print farm. It used around $300-400 of material at retail prices, plus some extra for the epoxy and foam used to assemble it.

The finished product was killer, though, even if it looks a little rough around the edges. It rolls and pivots just like the real thing.

We don’t feature a lot of chair hacks on Hackaday, but we do feature some! Video after the break.