My version of a pivoting hitch with minimal rattle. I don't know if I would do it again vs. buying a lock-n-roll but was a fun challenge. I used fj60 bushing eyes off of a frame, 60 bushings and 3/4 bolts which need to be downsized if you don't have old bushings for the U joint and 7/8 x 1 5/8 DOM with a 7/8" bolt for the pivot. This is for my M416 .
That part is the fj60 bushing tube cut down, welded to another cut the same but welded together with a 1/2" stub x 1" wide, then turned 90 degrees . A simplified version would just use a solid chunk of steel with holes in it. It is basically a U-joint. There are several commercial and home made versions of this. I liked the idea of rubber bushings for ease of replacement but I don't think it is necessary
What I meant was how is the rotation about the trailer frame center-line done? Pitch (Up/Down) and Yaw (Left/Right) are pretty clear on how they're done. I used OEM rubber FJ60 spring bushings for the engine mounts in my aborted V8 swap, so I fully appreciate what you're doing there & agree with it.
As mostly design exercises I've messed around quite a bit with designs similar to what you've built. I've pretty good idea of the challenges you ran into. Even tried once to see if I could design to use two of the HF Clevis Pin sliders as the basis for cheap, easy to build at home kit. The "wrist" or chassis center-line rotation part has been the biggest problem in all of my approaches.
The centerline-articulation must be happening. I assume here it's a factor of the combined Pitch and Yaw, but can see how friction/resistance in the rotating assemblies could cause problems. Is this where articulation is a problem or you anticipate it to be? I know some use a rotating receiver mount, similar to how a pintle or lunette rotates, to deal with this.
I'm sticking with my pintle for now, but like to keep up with the alternatives.
Notice the nylox nut poking out of the one yoke, there is a 7/8 bolt with a square washer tacked on then its sleeved by 1 5/8 x .250 DOM welded to the 2" tube- the bolt doesn't rotate but another piece of DOM welded up to the yoke does. Its a cozy fit, no wobble. A grease zerk would be a nice touch. I found a similar design somewhere utilizing parts from Tractor Supply. It's tough to find the right sized parts without having to have stuff made or the tools to make it yourself- like a lathe.
Notice the nylox nut poking out if the one yoke, there is a 7/8 bolt with a square washer sleeved by 1 5/8 x .250 DOM welded to the 2" tube- the bolt doesn't rotate but another piece of DOM welded up to the yoke does. Its a cozy fit, no wobble. A grease zerk would be a nice touch. I found a similar design somewhere utilizing parts from Tractor Supply. It's tough to find the right sized parts without having to have stuff made or the tools to make it yourself- like a lathe.
Big drill bits aren't cheap, hole saws aren't too expensive but these are costs to consider. I like the simplicity of that design. I really like the quick release option but a hitch pin will work too in the receiver.
I'd be making sure I had trailer chains with that 2nd link. The "very strong tee" doesn't look that strong to me.
Edit: so posts below make sense. The 2nd link I mention refers to the "Under $50 DIY 3-axis coupler" hyperlink above.
If it swivels and turns the real stress would be bumps, stopping and accelerating. I'm no engineer but the little pins that hold the hitch pin seem hokey but they work.
I'm a mechanical engineer with enough machine design experience. I wasn't judging yours, but rather the one linked with the really thin walled tubes welded into a tee. Yours appears thicker and more up to the task.
