I really don’t know if I could find a dryer subject to write about than industrial springs. At least a subject that sounded dryer, because when I actually started to read about them it was obvious that there is a lot more to a spring than most people would imagine. First of all, I’m not sure that most people really understand how many springs end up in products that we use every day. Just sitting at my desk I can see more than a dozen items that have springs in them, including ball point pens, various remote controls (the springs hold the batteries in place), a clipboard, the chair that I’m sitting on and even the keys on my computer.
They also find their way into just about every home appliance that you own, in life-saving medical devices and there are hundreds of variations of all sizes used in industrial settings. All of these these springs have just as much in common as they do differences. While they all may seem to be quite similar, they actually are made and function in completely different ways. Things like the spring’s diameter, the material it’s made from, and the number of coils that it has are all things that will completely alter a spring’s behavior.
One of the most common varieties of a spring is the compression or a torsion spring, which produces tension that can be used to produce a squeezing effect on an object. Think of the type of spring that you would find in a standard clothes pin, or on a clipboard. The force of the spring holds the clothes pin closed, but a simple push flexes the string and opens the pin. A tension spring is also extremely common, and they are used to stretch or extend as weight is applied. These would be found on a trampoline or a garage door opener. And of course everyone knows what a coil spring is as they make things like ballpoint pens function.
Since 3D printers are not really capable of producing a functional spring, what exactly does a 3D printer have to do with a spring? Rapid prototyping of course. The spring manufacturing industry relies on precision to make springs that function exactly as needed in the limited space that they tend to be installed inside of. Especially considering that there is a very good chance that most product designers are not even aware of exactly what sort of spring is required, or the function that it is intended to serve. Most spring manufacturers are generally consulted to fabricate a spring that performs a specific function, and must do so in a space with not even a spare millimeter clearance.
However 3D printing prototypes of the product has given spring manufacturers the ability to ensure that the spring dimensions are accurate, and once it is fit they can make sure that the spring can actually be fabricated. Not only does this pre-fitting process reduce waste as the spring makers no longer need to run through dozens of iterations, but it also saves valuable time and money. 3D printing is also regularly used to create gauges, or tools that make sure each spring is manufactured to the same size and shape. So after a new spring is manufactured it can quickly be compared to the gauge, which measures everything from the size, thickness or shape that is needed. This prevents the possibility of any slight variation that may make the spring itself work differently than required.
Ultimately there are multiple ways to manufacture a spring, each of them requiring specific machinery to correctly and accurately tool them. Most large-scale industrial quality springs are made using a CNC (computer numerical control) machine. The KCT680 CNC coiling machine manufactures compression springs, and allows the user to alter the size, number, and diameter of the coils, not to mention the distance between each of the individual coils. Some of the slight variations are so subtle, but can make each spring act entirely different, that they need to be color-coded so the wrong spring isn’t used for the wrong application.
I think the fact that 3D printing is becoming a very common tool for spring manufacturers is a testament to how remarkably versatile 3D printing can be. It is likely that within the next decade or two there won’t be a single industry that won’t have uses for additive manufacturing technology in some capacity. 3D printing is going to continue to reduce the time and cost of developing all of the products that we use on a day to day basis, and it is likely that one day they will even be used to fabricate the springs themselves. What do you think? Discuss in the 3D Printed Springs forum over at 3DPB.com.