Weblog > Cmetric Classic
elogIQ is a company based in the USA and founded by mathematicians, educators and psychologists that work together to bring us original and creative brainteasers. Dror Rom, inventor of the Cmetrick Classic, which I’m reviewing today, patented his creation in 2004 and since then three other versions have been produced by elogIQ: the Cmetrick Classic Mini, the Cmetrick Too and the Cmetrick Too Hard.
The Cmetrick Classic is a sequential movement puzzle consisting of nine identical spheres arranged in a 3×3 frame, with each sphere having six different colors. The mechanism of the puzzle is comprised of twelve cogs that connect the spheres in such a way that when you rotate a single sphere in one direction, all three spheres pertaining to that same direction will rotate in sync. For example: if you rotate the top left sphere horizontally (left or right), only the three spheres in that row will rotate as well. On the other hand, if you rotate that same sphere in a vertical direction, then only the spheres in that column will move. The object is to mix the spheres and then return then to the same orientation with all colors pointing to the same direction.
The mechanism of the puzzle is quite ingenious, but at the same time a bit rudimentary, which can be very frustrating at times. The movement of the spheres can be anything but smooth, as they get jammed or misaligned pretty easily at the slightest mistake. In order to prevent this, you need to make sure, at every movement, to have all sphere holes perfectly aligned, or else disaster happens. Rotating two spheres at the same time in the same direction also helps. If you get to the point of no return, and believe me when I tell you, you most certainly will, there’s a quick fix for it though, sort of…
The designer of the puzzle knew of this setback in the mechanism and thought of a simple way to fix the problem, instead of leaving you with a broken puzzle. On the edges of the frame there are clips holding the two sides together. These are very easy to come off and when you do so, just hold the sphere that is not out of sync and by rotating the one that is, you should be able to fix it.
With the out-of-sync problems out of the way, let’s move along to the actual playability of the puzzle. Getting the spheres all mixed up is a piece of cake and actually quite fun. The challenge begins when you try to get them in their original arrangement. To get a good sense of the puzzle and how the sequential algorithms play, you can attempt to solve it by the top color only, regardless of the orientation of the side colors. After practicing this less complex task, you can move on to the actual challenge by getting all colors with the same orientation. There are much more complicated sequential movements here and even for me they’re a bit tough to grasp. I’ve managed to eventually solve it, but not in a way that can be solved again without a struggle.
I wish the mechanism of the Cmetrick Classic was a bit more sophisticated, but jammed movements and out-of-sync problems aside, it is a fun puzzle to play with and a great challenge if you love this type of brainteasers. If you can get past these minor issues, it’s well worth a try.
Jaap Scherphuis has a comprehensive analysis on this puzzle and a step by step solution at his website.
Check out this animated video of a Cmetrick Classic being solved.