Geometry:
Tricopter 9DS is similar to my Tricopter 9 Pillow puzzle, but in this case the jumbling cuts have been moved deeper, and the non-jumbling cuts have been moved shallower. The puzzle has a total of nine axes, one at every edge. Moves on these axes can be combined in any order, and there is no overhang bandaging. This makes the puzzle extremely complex as it jumbles and shape shifts constantly.
Other Items Needed:
Dye: If you want the puzzle to be black, you can save money by dyeing the pieces yourself with a nylon dye such as RIT or Dylon. Or Shapeways can dye the parts for you at an additional cost.
Stickers: Template available in the instructions forum. If you want professionally cut stickers, I recommend Oliver’s Stickers. Use a hair dryer or other heat source to get the curved stickers to conform to the spherical surfaces.
Screws: Six 12mm M3 pan head screws required, available in hardware stores or on the web.
Springs: Six springs needed, available in web puzzle shops. I get mine from HK Now Store.
Degree of Difficulty:
Assembly: Inside-out core requires moderate dexterity to assemble.
Solving: Extremely difficult to solve.
Playability:
Tricopter 9DS turns easily, and the mechanism is stable.
Have fun!