Internal combustion is a nice framed burr puzzle available in a number of formats. This version, available from Puzzle Master is made from a block of aluminuim. Other versions are available, and I have seen copies of the puzzle made in wood. The object is to remove the four ‘pistons’ from the frame. Thanks Puzzle Master for sending me this puzzle to review.
At 2 1/3″ square by 1 1/3″ high, this is a pretty solid little puzzle. Given that the version I have is made from aluminium, it’s a heavy little puzzle, and really feels good when you’re solving it. I was pleasantly surprised when I started playing with this puzzle that the fit of the pieces was fairly good. I had expected it to be a lot less precise as a mass manufactured puzzle, however that wasn’t the case at all. The movement of each of the internal pieces is smooth and makes the puzzle easy to work with and fun to solve.
As the name suggests, the movement of the pieces when you’re solving the puzzle is much like that of an engine. Each of the pieces is required to move back and forth much like the pistons of an engine to free each other piece, and eventually remove the first piece, then each of the other pieces in turn. I really like the movement when solving, it has a rhythm to it that you can’t help but enjoy.
It took around 20 minutes to solve the puzzle, then return it to its starting state. Puzzle Master rates it as Level 8/10 – Demanding, which is a fair rating. It’s certainly tougher to put back together than to take apart, especially if you leave the pieces jumbled for a while before going back to re-assemble it.