Barcode Burr

I’ve finally gotten around to playing with Barcode Burr and what an amazing design it is.  It consists of 6 mostly identical pieces that form a mostly complete cube.  Mostly identical, because the pins and mazes on each make them unique.  Mostly complete since there are grooves in the pieces.

Barcode Burr was developed by Lee Krasnow and was originally made in wood with metal pins.  Each piece had an identical pattern on the outward facing sides that meshed with the other pieces to provide an amazing pattern when the cube was assembled.  It was entered in the 2004 IPP Nob Yoshigahara Puzzle Design Competition where it won an Honorable Mention award.  Stiff competition that year.

To provide a more economical means of providing puzzles like this to the puzzle community, Lee eventually created his own 3D fab lab to print his fabulous puzzles.  Not only was Barcode Burr made available but also other code burrs using the same overall format but different mazes.  There are now 17 different designs in the Barcode Burr family.

For these puzzles, each piece is comprised of 3 components.  There is the main body of the piece that makes up the outer shell of the cube and 2 other components that allow for customizing the maze and pin configurations.  One is a long protrusion that mounts to the main body and the other is a plate that mounts onto a shorter protrusion on the main body.  Each of these pieces supports interacting with an adjacent piece on 2 sides providing a total of 4 other pieces that each piece interacts with, i.e., all but one other piece.  Since pieces on opposite corners move along the same diagonal line, albeit in opposite directions, it is not possible to have them interact via a maze.

Not wanting to bite off more than I could chew, I decided to start with the rainbow colored Barcode Burr.  Why rainbow colored.  Because, I was a bit concerned that if all the pieces were the same color, it would be more difficult to determine where each piece goes and the order that they have to go together.  AND, there are 3 solutions with 2 being non-intended solutions with shorter solution paths.

To be honest, once I started playing with it, the colors and the expected movements took away any intimidation I had expected.  It was just fun.  I’ve taken it apart and put it back together several times just for the fun of it.  When the pieces start coming out, it does get a little fiddly but never falls apart.  At some point, I’m going to have to try the single color version and scramble the pieces to determine how difficult it is to solve.

As of now, Barcode Burr appears to still be available in Lee’s shop Pacific Puzzleworks if you want to get a copy of your own.  It’s well worth playing with.

Three Caterpillars

How many caterpillars does it take to make a butterfly?  No clue!  But apparently, it takes more than 1 to make a symmetric shape.

Three Caterpillars is a 2D symmetry puzzle designed by Alexander Magyarics.  You may never guess that it consists of 3 caterpillars that need to be arranged to make a symmetrical shape.  The type of symmetry is not specified.  And if that is not enough, each pair of pieces can be used to make a symmetric shape as well.  Four challenges for the price of one.

The pieces are 3D printed and the heads are a different color than the rest of the body so you know which way they are looking.  The colors have no relationship with the symmetry constraints unless I completely misjudged it.

The 3 challenges for making a symmetrical shape with 2 pieces are not that difficult and make for nice warm-up to the main challenge.  The 3-piece challenge is a bit more involved than the 2-piece challenges but I didn’t find it as tough as some of Alexander's other symmetry puzzles.

Update: Alexander contacted me and indicated that the solutions do indeed have to take into account the symmetry of the colors. 

One Match Left

I recently had the opportunity to acquire some 3D printed hand-me-down puzzles from a kind soul on the Mechanical Puzzle Discord (MPD).  Among the nice selection of puzzles was a copy of One Match Left.

One Match Left is a 3D packing puzzle designed by Jorgos Anastasou.  It consists of 3 pieces that need to be packed within a cubic tube.  Both ends of the tube are open and there are 2 protruding obstructions on the inside that keep the pieces from simply falling out.  One is single voxel and the other is a double.  Two of the pieces look like burr pieces and the third is in the form of a match.  The version that I received was printed with extra attention to detail to make the match piece look like a match with a white body and black tip.

This puzzle is one of Jorgos’ easier puzzles and not difficult to solve.  Determining how the 2 burr pieces are oriented within the box and where the match goes is straight-forward and once you have that, putting them all within the tube is a quick process.  One Match Left is a great introduction for this type of puzzle and good warm-up for tackling more difficult puzzles of this type like 4 In Frame (Foreign Fame - 4 In Frame) or Wheel Lock (An Impediment to Rolling Along - Wheel Lock).

 

Gears

Not being much of a gearhead, I was a little apprehensive of tackling Gears designed by Hirokazu Iwasawa (Iwahiro).  It is a 2D restricted-opening packing puzzle made by Constantin Puzzles that Iwahiro used as his exchange puzzle at the 41st International Puzzle Part (IPP).  It consists of a frame with a hinged door on the side that can be opened to allow gears to pass through.  There are 9 gears in all.  2 of them are fixed in the center of opposite sides of the frame and can rotate freely.  The remaining 7 loose gears are the same size and have the same number of teeth as the fixed gears except for 1 that lacks teeth.  The frame also has a large opening in the clear acrylic top in the shape of an I to provide a means of manipulating the pieces when they are inside.  Lastly, there are a couple of pointy bits in the frame to throw a wrench in the gears.

The objective is to add all the gears to the frame and close the door.  I started to putter around with adding gears but it took a while to get the gears turning, in my brain that is.   It all starts out easy enough, but as more gears are added, they need to rotate as they pass through confined spaces eventually leading to gears disagreeing on which direction they should be rotating.

Shifting my brain into high gear, I finally settled on where the toothless wonder needed to be.  Of course I tried all the other places to rule them out for certain.  Even then it was not obvious to me how to proceed.  Eventually, I shifted gears and tried something a bit more complex that set the machine in motion and allowed the lid to close with all the gears inside.  A very nice AHA moment.