I re-created this old (1911) puzzle from some youtube videos using Glowforge materials. You rotate each of the wheels until each of the 16 columns adds up to 40. It was a little tedious finding all the numbers through the videos, but it worked out. SolidWorks was used to create the profiles for the wheels, and Illustrator was used to lay out the numbers.
Matt
That is really cool!
Very cool
Very interesting puzzle! I like the mix of wood for this.
Clever and fun!!
Very impressive! What ever made you think to look up a game from 1911? Did safe crackers actually use something like this to practice? Makes you wonder doesn’t it? 
It’s a very popular/common puzzle for those into that kind of thing, available for as little as $3 online.
Huh! Never seen one of those…doesn’t look easy! Like Sudoku on steroids! 
(Great build!)
Awesome find
Matt,
Would you be interested in sharing your knowledge on how to understand the construction of the puzzle?
Craig
Sure.
First, there are lots of folks selling these puzzles online, so you can pick one up for $20-40 if you want. I have attached a spreadsheet that has all the numbers that go on each ring. The “Biggest ring” has an outer ring of 16 numbers and an inner ring of 16 numbers. All the subsequent rings are notched so the outer ring has 8 numbers and the inner ring has 16 as is reflected in the excel file.
Note that there are actually two puzzles I reverse engineered. one that adds up to 40, and another with one more ring that adds up to 50.
Artwork was done in Adobe Illustrator. I found the easiest way for me to deal with all the rotated numbers was to create a “00” number at top dead center, then copy rotate it 22.5 degrees 16 times. Then when they were all laid out, I just went back and edited each number using the spreadsheet. I created all the lines and notches the same way. Make sure your font is small enough to fit in the smallest ring!
The spreadsheet also contains an image of the solution to the “40” puzzle.
Matt
Safe Cracker numbers.xlsx (659.1 KB)
Thank you. I was looking for the challenge of making one as a gift for my son. He is a gamer!
Craig
This is so cool! My head hurts already 
Every time I see something like this I regret my dad never had a GF. He used to make and design his own puzzles, but mostly from wire - like an interlocking set of his initials. He loved working with wood,though.
