Markforged revloutized 3D printing with a new material.
Since the launch of the new Onyx filament, Markforged’s applications team has been testing the limits of this industrial strength 3D printing material and are still discovering new ways to use it.
Let’s take a look back at the frist part printed in Onyx: 3D printed shock absorber springs.
So let’s start from the beginning.
As you may have seen from the reinforced living hinges post, I (Alex Crease) have been experimenting with the flexibility of the filaments. While Onyx is stiffer than Tough Nylon, when it is not reinforced it is still a bit pliable. When originally testing its overhang tolerance to showcase dimensional stability.
Originally to show how it handled overhangs and realised…it also functioned as a spring!
It turns out that Onyx is strong enough and flexible enough in the Z direction to actually allow for 3D printed springs, both for extension and compression.
By altering the dimensions: thickness, coil diameter, pitch, etc, I figure you can adjust the spring constant to create different damping behaviours, but this has yet to be tested.
The compression spring was just a 3D printed coil with no support material, while the extension spring I actually designed with two coils, essentially making two springs in parallel. Both were printed without support material, so in the extension spring design, each section of coil is actually resting on the section below it.
Taking it another step further to create the shock absorber. Instead of printing the springs exposed, I enclosed them in a cylinder and added a shaft and mounting holes. Everything in Onyx is actually a single part, so it is all connected.
Note that there are actually three parts in this shock: the largest part is the main body, which includes the cylinder, shaft, and spring all connected and printed as one piece in Onyx.
I was concerned for the friction between a few of the surfaces – including the spring contacting the inside wall of the cylinder, and the shaft rubbing against its hole through the top of the cylinder, so the other two pieces are printed in nylon, as Nylon is a bit smoother than our Onyx filament, and nylon is commonly used for bushing material.
And there you have it, a fully 3D printed shock absorber.
Read more about the original article and see the full 3D printing process – Click Here.