CrabMaze 1

Based on the “FASTMAZE” metal puzzles by Dan Fast, this is a similar, but original maze puzzle which you can 3D print. There are 3 plates and 3 pins. The pins are square in profile because the maze can be solved by only using X & Y (linear) movements. No rotation of the plates is necessary, but likely the plates can mechanically be rotated at your own peril. In general, the square pins will prevent rotation at most points in the maze. Because parts are made in plastic, movements could be forced … breaking edges or pins. However, very little force is necessary and often a slight jiggle of the plates can bring them back into alignment. 

The maze has a Level of 42 (18.10.4.6.4). This means there are 18 linear movements to free the first pin. Then 10 moves to free the next piece. 42 movements can free all 6 pieces. 

Each plate is 6mm thick which I've printed in both PLA and PETG. The pins are 18.4mm between the knobs which allows the plates to move freely. The plates have 1 to 3 holes in their sides to indicate orientation and position. The starting position has the plate with 1 hole  on top, 2 holes in the middle plate and 3 holes in the bottom. The holes should align for proper orientation when starting. If you get stuck, you can dismantle the pins, align the plates and redo to the starting position described and shown in the picture above.

The most complete pin design uses a 12mm M3 screw in the pin bottom for strength and an M3D5L4 heat insert on top to allow the knob to fasten. The knob uses a 10mm M3 screw with a square M3 nut. I find the pins print best with PETG but PLA also works fine. There is an optional “basic” pin provided that only requires a single 10mm screw that goes thru the knob and will screw directly into the plastic of the base pin. This basic pin will require a screwdriver to undo and reset the puzzle. If you install square nut into the knob, you should be able to unscrew it, even if you don't use a heat insert. The insert makes the knob much easier to remove. 

I printed all parts with 0.2mm layer height. I used 70% infill on the plates to give them a more solid feel. I used 4 walls for Top & Bottom.  The pins were  printed with enough perimeters to basically make them solid. I allowed for a 12mm M3 screw to install into the base bottom for extra strength. This is totally optional and may not be necessary, but I wanted to make it somewhat bulletproof in strength. 

This puzzle only uses 3 pins, while the FASTMAZE series uses 4. And so this puzzle can be a good introduction to Dan Fast's offerings, should you want to consider similar challenges. 

Hopefully, you will find the puzzle challenging. It helps to play with the maze for some time before one understands how the plates interact. It is not designed to be solved quickly and could take a few/several sessions to work out a successful path. 

In the model above, I used PLA plates and PETG pins. I printed on a rough sheet and used a manual filament change for the red icons.