Rod ends for SBU shifters

Did not see anything on Belmetric site, but McMaster-Carr has a pretty large assortment of ball ends, assemblies and rods. Might be easiest to just make what is needed.


One possibility from that link:


Don’t know if the ball stud is threaded, or a peened over interference fit, but one could always drill and tap for a slightly larger thread size for the ball stud.

All FWIW

Lee

Hmmm.....

My take is that load limit of the part is not too important. The force applied is basically aligned with the rod, via the metal ring of the joint, and not perpendicular to ring or rod (totally different situation). This means the plastic piece is a bushing, transmitting a (probably light) compression load from the ball stud center point into the ring, and longitudinally down the rod to the next ball joint, and onward as above. The ball end allows for angular movement of the joint/ rod, but keeps the forces centered. There is little or no force that would try and pull the ring off the ball stud, as evidenced by the lack of a "keeper" on the OEM part.

My bigger concern (and it is not a big one at all) is the bending strength of the connecting rod, to resist the compression loading (tension not likely to be a problem, no bending there). On my truck, the moonlighting M-B mechanic who installed the working gears while the truck was still in Belgium made a a linkage using a fairly small diameter threaded rod, and not even grade metric 10.9, at that. No issues whatsoever, I have looked at this and thought "I should do this up right", but when it works for thousands of miles, that task falls pretty low on the list (meaning: not done, not even thought about agaIn until now).

Take a look at the gas struts for hatchbacks, etc. Some of those have really high pressures, and rarely fail; when they do, it is usually loss of gas pressure. My RW1 drop sides have 250# struts, and they are not of massive diameters, rod or ball, and the only non OEM (after 35 years) one is the one I busted apart by doing something really stupid (sideways).

All FWIW

Lee

I am kind of a fan of the "brute force method", that is, just figure out what is needed and go knock it out, step by step. In cases like this, I think it is quicker and less brain strain than trying to finesse a solution with "proper" parts.

Faced with this problem myself (which I am supposed to be, see earlier post), I would get a set of ends and compatible ball end studs from our favorite source, and then drill/ weld/ etc as required to mate the ball studs to the shift arms. I would try for a lefthand/ righthand threaded pair of ball ends, to give the turnbuckle effect in the finished assembly, but that is not essential to the concept.

As for the rod, I would also order up a piece of steel tubing with an ID greater than the OD of the threaded rod ends of the ball joints, and a pair of grade 8 nuts (hopefully left & right hand threads), or possibly a pair of rod couplings, to match those threaded ends.

Cut to length, then (TIG) weld nuts/ couplers on each end, let cool, install, adjust. Done.

A trick on the welding: run a smaller diameter threaded rod through the tube and the nuts, add washers and nuts on each end, tighten. If cuts are square on the tube, this jigs everything up nicely.

Lee