💬 Re: 36" Maiami Crash boat used for camera boat.
Agree completely Doug, but I didn't want to muck about trying to make strut bearings etc. This way if the bearings clap out there are only 2 to replace and if all else fails, a pair of vice grips on the end of the tube gets the whole thing out real easy, chuck a new one in and you're away. Trying to replace a bush/bearing in a fragile strut (unless removable) without damaging something, would be a tricky operation I would imagine.
Most nitro boats in the past were made like this until cable drives came along (before cables, the only thing close to an open shaft on a fast model was a 'zip strut' which involved an underwater universal (see Seafury). The reason was mainly a torque issue, as if you just had a 'T' strut and open shaft, the torque from something like a hot .60 powered boat jumping out of the water was enough to bend the strut on landing, so you needed quite a substantial 'T' or better, a 'V' strut, (I even had heavy struts as well as the tube, -see pic,early 70s - strut was about 4mm thick on a .40 boat). Check out the cable drive strut size on a big model hydro or mono for eg.
A lot of kit manufacturers like Dumas,(see pic) used full length stern tubes for a number of their models
, - probably more for ease of building rather than going for the full 'scale' bit. The term I've always known the 'outer tube by is a stern tube but there are probably a number of variations.