Octahedrik Puzzle

Six pieces, all different, can be assembled into an octahedron.  This puzzle was invented many years ago by Rik Brouwer, who has approved its appearance here. Rik made several in wood and more were manufactured and sold. I include the document which was included with the wood version (translated from French into English courtesy google translate). I use the same piece numbers as this document.

Pieces 2-4 do not need supports.  Pieces 1, 4 and 6 have an edge against the bed, and need small support areas.  The enclosed 3mf files are for printing the pieces in pairs.

The assembled octahedron has an edge length of 6 cm and is beveled.  The pieces have an offset of 0.05 mm.