When you think of a puzzle lock and how it should be solved, the first think that comes to mind is probably: how do you unlock it? What's its locking mechanism? It's a fair assumption, given how puzzle locks have been presented before. However, designer Jin-Hoo Ahn (who also designed the Cast G & G) takes a completely new approach and makes us think of puzzle locks in a whole different manner with the Cast Padlock. The theme for this puzzle is "obstinacy".

Although it appears like a regular puzzle lock, the Cast Padlock doesn't have a functional keyhole. You won't be unlocking it, but rather taking it apart. Four pieces make up this intriguing design, but in order to solve it, you'll definitely need some "obstinacy". What's more, the solving process is not at all straightforward, so be prepared for a tough challenge.

One aspect of the puzzle that stands out immediately is its tiny size. This a puzzle that measures only 4.3cm x 3.3cm (1.7" x 1.3"). IT's a tiny devil, is what it is...

The four pieces that comprise the puzzle can rotate freely around the common central point. But, alas, rotating the pieces alone won't get you anywhere. You need to find an exact position that lets you separate the round semi-circles, but for that the two elliptical pieces in the middle need to be positioned correctly as well. It's a discovery journey in itself, as you learn how the inner mechanism works and keeps the pieces interlocked.

I found this puzzle extremely difficult to solve. It took me a few days to completely understand how the pieces interacted with each other. As if taking it apart wasn't a hell of a challenge, putting it together again is no small feat. This is rated as a level 5/6 by Hanayama, but in my opinion it's definitely a 6/6. If you like your puzzles crazy difficult, I can highly recommend this one, and you won't be disappointed.

Solution: If you need the solution for this one, you can download it here.

Closing Comments:

The Cast Padlock is unique. There is no similar design out there and so, nothing to compare to or take hints from. It's a beautiful and awe-inspiring design, and therefore another worthy member of the Cast family.

Availability: You can easily find the Cast Padlock and all the others in the Cast series at PuzzleMaster.