One Person – Three Body Problem

At this year’s International Puzzle Party (IPP), I overheard Girish Sharma say that people smiled when he told them the name of his puzzle, Three Body Problem, during the IPP Puzzle Exchange.  I know it didn’t make me smile – maybe cringe-worthy.  All I could think about was complex coordinated movements in physics with no general closed-form solution.  Turns out I’m just socially stunted and not tuned in.  3 Body Problem is the name of a series on Netflix based on a novel by Liu Cixin.  However, I may have been on to something since the puzzle does indeed require complex rotational movements.

Three Body Problem was designed by Girish Sharma and used as his exchange puzzle at IPP41.  The puzzle is nicely made with Maple, Cherry, and Mahogany by Brian Menold at Wood Wonders.  And dowels were used to reinforce end grain glue joints.

The stated goal is to interlock the 3 pieces within a 4x4x4 space.  It also promises some rotational moves in the solve.  Removing the 3 pieces from the box, it’s obvious that they are not going to fill the 4x4x4 space and won’t even cover the exterior surface like the many amazing turning interlocking cube (TIC) puzzles created by Andrew Crowell.  I used to see this as a sign of an unfinished design but to be honest, this puzzle is awesome.

Although this puzzle calls for 3 bodies, I thought I would tackle it solo.  However, it took me 3 times longer to solve than I expected.  I sat down with it several times before I finally had all 3 pieces packed together.

The final assembly was never really much in doubt, although I was required to doubt it a little since it took so long to find the solution.  However, the rotation supported by the half corner cube pretty much forces you to believe in the assembly.  It’s that crazy dance of the third piece that eluded me several times.  The problem is that you need to envision it from the end back to the beginning and there are so many steps, it’s not easy to run through.  Along the way, I found some interesting moves that I thought would be required but didn’t lead anywhere.  Eventually, I found my way to the final assembly.

I also enjoyed coming back to it a couple of days later and found that it took me several minutes to get it back apart.  To say that rotations are required is an understatement.  Being a fan of rotations, I really found this to be a great puzzle.  I’m sure the Netflix series plot has many twists and turns if it is anything like the puzzle.

 

All Corners, No Corners – 4 Piece Jigsaw

4 Piece Jigsaw was designed by Haym Hirsh and used as his International Puzzle Party (IPP) exchange puzzle for IPP41.  As indicated by the name, there are 4 jigsaw puzzle pieces that have to be placed in a square area.  Of course none of the pieces have a straight edge, making them all edge pieces without an edge or since there are only 4, all corner pieces without corners.

The puzzle was made by Nothing Yet Designs using laser-cut acrylic.  Going with the US based IPP red, white, and blue theme (as opposed to, for example, a bleu, blanc, rouge theme for France), the puzzle was made with a white frame and red and blue pieces.  The frame consists of 2 layers of acrylic that are bolted together with the bolt caps acting as tray legs.  Mine needed some tightening, so make sure you don’t unexpectedly loose yours.

Typical jigsaw solving starts with separating edge pieces from middle pieces and then pulling out the 4 corner pieces from the edge pieces.  With only 4 pieces, you would expect all the pieces to look like corners, but you realize that this will be a puzzle without a clean exterior edge.  All the pieces are middle pieces.  It’s kind of like asking for an Oreo cookie without the cookie part.  Admit it, you know you wanted to.  Just the middle please!

Each edge of the puzzle pieces has either a knob or a socket with each piece having 2 of each on opposite edges.  The knobs and sockets come in either single or double size and can be located in the left, right, or center position, or in the case of the double size, 2 adjacent positions, which always includes the center. And unlike a typical jigsaw puzzle, the pieces don’t have a designated top and bottom, so they can go either way.

The first stage of attacking this puzzle is to rule out some often-used packing tricks.  After getting those out of the way, you basically know how the pieces are going to be packed in the tray.  I was anticipating an expected Aha while pondering whether the Aha was that there wasn’t an Aha.  Trying both Aha and meta-Aha assemblies, I eventually found myself at the solution – Ahahaha!

Being a puzzle designer myself, after I solved the puzzle, just for the hell of it, for no particular reason at all, not that I would ever think about it myself, I checked the kerf angle of the pieces to determine if they were all aligned with the orientation of the solved puzzle and it looked to me like it was.  So don’t cheat and orient the pieces based on the kerf angle, not that you would ever think to do that.  This isn’t a real problem with laser-cut cut pieces like 4 Piece Jigsaw since you really have to go out of your way to determine which way the kerf angle is oriented, but it’s a huge problem if you 3D print the pieces where there is an obvious plate side and top side.

4 Piece Jigsaw is the first of a series of jigsaw puzzles designed by Haym and available at Nothing Yet Designs.  JIGS4W (all 4 pieces are the same color) appears to be the new name for 4 Piece Jigsaw and the next 2 in the series are JIG5AW (3 sets of 5 pieces) and J1GSAW (10 pieces).