yeap, instead of switching, he could just make a planar spring (like a sinusoidal slender segment) and you should be fine. PLA makes quiet good spring (because of their comparative high young modulus, you need less mass to store the same energy compared to other plastics) if you design them well (limit max deformation to low values (no more than 6%)) and in applications where the spring forces only matter at transient states (so you avoid creeping)

@@giuseppebonatici7169 yes but that kind of deviates from my initial consideration. The shape you are mentioning, and pretty correctly, would be a spring itself. I'm talking about rigid parts. If you can call them rigid. He he he

@@giuseppebonatici7169 Very important last bit, was gonna comment on that, PLA having as much creep potential as it does, any PLA spring would be necessarily unloaded most of the time to be reliable in the long therm (heck maybe like, days). I always go with ABS whenever possible for any part that stays loaded in a way or another, when not possible PETG is my go to material.

something something everything's a spring

@@satibel indeed it is. However the trick in this is the balance and harmony of plasticity and elasticity. Given that you can't change the parameters at will, you have to go through the design route. And that requires some knowledge on materials and/or "touch".

Do you have some links who explain all of those mecanism ?

What other systems do you use?

While many people say a bigger nozzle can produce stronger prints i've found the opposite to be true bc of the reason you stated, i speak from experience working with figurines, tended to prefer bigger nozzle sizes until i realized it.

Do you mean have air gaps between perimeters? It makes sense that it would bend easier, but will it really help with elongation?

@@polycrystallinecandy Yes, that's what I meant. And the answer is "kinda". As stated, PLA is awful when it comes to being a spring. But material structure is quite intruiging and the finer you go with a given material, the more "springy" it becomes. The best example are modern phones, or to be more precise, their accelerometers. These are nothing but nano scale silicon parts that flex with amounts that would shatter the same material if it were a millimeter thick. Same way how the fine stranded copper wires can be bend and twisted fine (within reason), while the single strand versions, meant for permanent placement, would work harden and break rather quickly from the same bending and twisting. Obviously, when printing springs with this approach, it comes with the cost of less stiffness. So experimentation is needed regardless. But the lifetime of the flexing parts would be drastically higher. Another benefit, more related to PLA in particular, would be that it's likely that only one spring "strand" would fail at first, and not the entire section. Since PLA often tends to reach critical failure with little warning, it would help to have several points that all are stressed differently in the same section, that way some can fail first as a warning before all have failed. But this depends highly on the design and applied forces. One design might even be better off, once one or a few strands have broken, another might overload all of them at once.

Agreed.

He really is haha. He’s a teacher.