Building a U-Joint

So, I determined it was time to replace the U-Joints on Missouri. The U-joints that came with Seydlitz were pefect for the job, so I went out in search of a matching pair this morning. Unfortunately, I got met with blank stares at my local RC Hobby shop (repleat with boats, planes, helicopters and cars - but a U-joint for a scratch-built boat.... unthinkable!), so I scoured the racks in search of suitable parts to make my own. 

The white U-joints are the models taken from Seydlitz, the black parts are the U-joint sub-assemblies I was able to acquire. There are also 4 lose (and 4 pacakged) 5/32" collars, a 1/8" brass tube (top) that matches the prop-shafts and the output shafts from the motors, and a 5/32" brass tube that fits inside the collars, and outside the shafts.

Here we see a cut-down U-joint end, with a lenght of the 5/32" tube. I force-fit the 5/32" tube inside the U-Joint base. There is a notch cut in the end of the tube, allowing the set-screw to press against the inner shaft, and provide rotational lock with the remainder of the assembly.

Full sub-assembly.

The other half of the assembly.

Fully assembled.

Since I didn't quite get these U-joints as short as the originals, I decided to use the originals in Missouri, and installed these longer replacements in Seydlitz. If the force-fit of the brass tubes winds up slipping, I can later put a pin through the assembly ends to prevent slipping.