Once again I've reached the limits of my experience. I'm designing a part and I need your help, obi-internet. Who knows how to build this right? I need to bounce this idea off you and see if it comes back sane.This is a side view cutaway of the anchor (bottom), shoudler (center) and boom (top left) of my latest attempt at an arm.This is a view from the rear, looking slightly down so you can see the holes and scale.The anchor is a lazy susan between two plates. The anchor bottom is bolted/clamped to the table. The anchor bottom and anchor top are bolted through the center and a small thrust bearing. The anchor top is (somehow) bolted to the shoulder. That's where I need your help.

I have a piston attached at the back of the shoulder and a bearing on the front of the shoulder. There's ~5N downward force on the tip of the arm. I want to be sure the shoulder isn't going to rip itself off the anchor. I want to be sure there's enough... bracing (?) so the shoulder doesn't fold over like a house of cards.

I haven't drawn the piece under the clevis because I have no idea if I'm working in the right direction.

Here are the dimensions of each part, in centimeters (cm).

This shoulder piece (above) is 1/4" wood. I can modify it any way I please. The large hole at the back of the shoulder provides access to the bolt that holds the piston on the clevis.
This clevis comes with a cotter pin and a bolt to attach to the piston. It's made of steel.
The anchor top is made of 1/4" wood. I can only make a few holes in the center, the rest is blocked by the lazy susan underneath.

I cannot yet afford a folding press and a water jet cutter. I have a 3D printer and I'm concerned anything I make will delaminate under moderate stress. My laser cutter can cut up to 1/4" on most woods. That means no folded pieces, no angled or sideways cuts into material.

So, mechanical turk internet experts, how do I do this with what I have?

PS: images hosted courtesy of imgur. Here's the gallery.