In the past, people made the wheels
In the past, people made the wheels of the skateboards of clay or metal. But with the advent of new technology and alternative materials, the wheels have also seen changes. In fact, since the 1970s, the material that manufacturers abide by is polyurethane.
However, depending on the type of boards you are using, the wheel material's consistency and weight would differ. Thus, whether you are buying the best longboard wheels or regular skateboard wheels, you need to check the hardness. It is here where a durometer comes into play.
What Is A Durometer?
This instrument helps test the weight and hardness of different types of plastics and even rubber. Thus, it makes for the right tool to check the wheels of skateboards and longboards. There are twelve versions of these measurement devices for hardness. The main classification for ASTM D2240 durometers are Types OOO, OO, O, E, DO, D, C, B, and A.
How Does It Work?
The way that durometers works are very similar to the different types of hardness tests. It checks any indentation visible on the material after using a standard presser foot on it. After that, the durometer would calculate the depth of said indentation and figure out the material's hardness.
Depth
Many points allow for this depth to occur. The main points in this concern are the material hardness, the presser foot shape, the material's viscoelastic properties, and the test duration.
Hardness
The durometers of the ASTM D2240 variety find out the hardness of the material first. Then they get the new measurement from the indentation created over some time interval. The object keeps getting equal and continuous pressure during the test. Throughout this period, the indentation depth is measured by the researchers to understand the hardness.
Plus, in some cases, the tests for the hardness checks are timed. In these situations, the researchers give force for a little while only, and then the hardness is calculated. The minimum thickness that is suitable for this test is either 0.25 inches or 6.4mm.
Points To Consider For Accuracy In Reading Measurement
When using a durometer to calculate any of the materials above' hardness, some points can affect accuracy. Focusing on the following would help you get good readings.
Pressure
When one puts pressure on the material with a durometer multiple times, you must do so consistently. And that counts for the amount of tension you apply in each interval. If you press the durometer with different pressure each time, that will affect the overall reading. The measurement you get then is null and void, and you have to restart again.
Faster checking
When you are using the durometer to calculate the material depth, keep your mind on the speed. The steps to hasten the process are simple. Grip the durometer on the surface of the tire using a footpad in an angular fashion. Slowly roll out the footpad until it is lying flat on the tire. After that, you can check the reading quicker and note down the information.
Same spot
Indeed, consistency is critical when you are calculating the hardness of the material. And that includes the placement of the durometer each time. Just put the tool at the same spot it was at previously. However, this only counts for the duration of each reading on the same day. Please do not keep it for longer; instead, take it out quickly. Otherwise, the rubber around the spot would deform, and you would get incorrect readings.
Temperature
It is imperative to check the temperature of the tire material as separate conditions give diverse readings. After usage, the temperature of the tires would automatically heighten up. In terms of physical consistency, they are comparatively lighter than new tires. A pyrometer would undoubtedly help to check the temperature.
In case you are looking for genuinely soft tires, you need to get the durometer checks during the same environmental conditions.
For example, one tire is facing one side facing the sunlight and the other toward the shade. The durometer reading for both sides would differ even though they are the same product. Thus, it is essential to check the temperature uniformly.