Modern cubes are have now advanced to the point where customizability is available in all price brackets, whether it be the budget or the most expensive flagships. The main adjustment system present in modern flagships is the spring adjustment system, a great tool for customizing your cube. Here we explain what the spring adjustment systems do, and the different forms of the spring adjustment system that are available on the market.
What do Springs in Cubes Do?
Most, but not all, modern cubes include springs in each of the center pieces underneath the screws, totaling in at 6 screws per face for standard NxN puzzles. When the center piece moves upwards, the spring places a force downwards onto the center piece, allowing the cube to stay in shape. Without springs, cubes become a floppy unenjoyable mess. However, these springs can have other effects on turning, as in recent times spring swaps and now integrated spring adjustment systems are highly prevalent in the 3x3 speed cube hardware scene in particular.
What is Spring Tension?
As long as not stretched or compressed beyond their elastic limit, most springs obey Hooke's law, which states that the force with which the spring pushes back is linearly proportional to the distance from its equilibrium length:
x is the displacement vector – the distance and direction the spring is deformed from its equilibrium length.
F is the resulting force vector – the magnitude and direction of the restoring force the spring exerts
k is the rate, spring constant or force constant of the spring, a constant that depends on the spring's material and construction. The negative sign indicates that the force the spring exerts is in the opposite direction from its displacement
So what does this mean? The higher the force exerted from the spring, making a puzzle more stable. Different springs have different values of k, changing the force output and in turn changing the stability and speed of a puzzle. Similarly, by increasing the x, the displacement factor, the force increases as well.
Different puzzles have different adjustment systems, which all change the forces that the springs exert, resulting in a more flexible or more stable turning experience.
What difference does this have to tensioning the screwhead in a regular cube?
When tightening the screwhead in a regular cube, it reduces the distance factor of the spring, making the force the spring exerts larger. However, this also reduces the full distance that the center piece can move upwards, resulting in worsened corner cutting in some cases. By having seperate systems, it alows for both parameters to be adjuusted individually.
MoYu debuted its first iteration of a spring adjustment system, which they named their dual adjustment system, as a purchasable extra for the WeiLong GTS (version 1). The distance of the spring is changed in the system, modifying x, the displacement vector resulting in a change force, and change in stability, when the tension is changed.
Source: MoYu-Cube Facebook
This system only made a return in a more robust, integrated form in the third GTS puzzle, the WeiLong GTS 3M, where again the distance can be adjusted in order for a change in stability and speed versus corner cutting and overall performance from screwhead distance.
MoYu have continued to use this mechanism in their following flagships, and budget cubes, in the WeiLong WR line in the 2019, 2020 and 2021 models, although a shift to MagLev technology instead of springs may be occurring in the near future with the WeiLong WR M MagLev.
GAN was a leader in the advancement of adjustable spring tensions, with the 356 Air the first of its kind have a robust interchangeable spring system, named "GES" (Gan Elasticity System) where each nut contained a spring that had a strength spring, changing constant k in hookes law. This became even more popular with cubes such as the Gan 356 Air Master, UM and SM, which came with multiple sets of springs that change the tension of the cubes. These required a specific tool to rotate the GES nuts.
The latest GAN puzzle to feature the interchangeable GES nut system was the 356 X, which was incredibly popular and also featured an adjustable magnet system.
GAN has traditioned to a dual adjustment system similar to that of MoYu's, where the spring distance and the height of the GES nut, which acts a screwhead, are adjusted individually. This was first featured in the GAN 356 XS, and carried over to the 356 X V2 and the GAN 11 M series.
However, in their own Pyraminx, Skewb and Megaminx, GAN have also included their interchangeable GES nut system for similar spring adjustment options that are present in their 3x3s.
QiYi were slightly late adopters spring tension hardware craze, with only their subbrand X-Man producing a flagship puzzle that has some form of spring tension adjustment through their own dual adjustment system.
A newer manufacturer to the speed cube scene, MS-Cube also has their own form of dual adjustment system in their flagship MS3L and MS3L Enhanced magnetic puzzles, with 3 spring compression options.
DaYan also has its own form of dual adjustment spring compression system in their Dayan Tengyun V2 M, the successor to the widely popular Tengyun V1. However, this puzzle did not gain as much popularity as the first version. DaYan also released a revival to their older Zhanchi line, the Zhanchi Pro M which uses the same spring adjustment mechanism as the Tengyun V2 M.