I am trying to make custom parts that fit directly onto a servo. Doing this has proved more difficult than I've expected so far.
I was hoping to avoid incorporating the provided servo horns into the 3D printed part, so I've been trying this method out. Below are images of my current test - a 3D printed attachment to the servo, with an indentation for an M3 nut (the servo accepts an M3 bolt) for attachment to the servo. The plastic ring doesn't have the spline (I can't print that level of detail I think) but is tight around it. The top piece attaches to a 3/8" nut for use with the 3/8" threaded rod I had laying around.
So far, I'm having difficulty of this setup working with any level for torque and not just spinning in place.
So... is this the correct approach? Am I going to have to design a piece with the servo horn inside of it to get the servo to connect? Are there better approaches I haven't considered?