Everyone knows that Veggie Sticks are stiffer than Sour Patch (especially blueberry flavored).
This is what happens when you try to bend them together:

This comes to show that the strength of a joint is shaped by the stiffer material, as long as we load them together.
As opposed to loading in series, like links in chain, or this:

Why the weird introduction?
It's my way of simplifying the key to making your next structure with 3d printed parts and other stronger and stiffer materials.
Going back to a more relevant example, my board serves me daily for the last 4 months.
The carbon tubes are perfectly capable of holding my weight (and then some).
But, there's no way to mount the trucks on tubes.
The 3d printed piece makes the mounting possible, and transfers the loads to the carbon tube.
PLA in this case is softer and weaker than the carbon tube, and it doesn't matter.
As long as the loading is in parallel, and there's a stronger part to hold the loads, carbon tube in my example.



Why not machine something stronger?
You could.
That means going custom and possibly investing in expensive equipment or ordering/paying high rates for small quantities/waiting for delivery.
Do you really want to invest your time this way?
How to make sure parts are loaded together?
Three simple tips:
-
- The fit should be tight, no slope or rattling.
- Achieve good bonding, roughen the surfaces before gluing, use a lot of epoxy.
- Make sure the load is transferred to both of the materials together.
Was this helpful?
What other structural things interest you?
Enjoy,
Dani
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