More work completed. Stuffing tubes fabricated Fitting to the hull. The vendor advertised these nylon props as 1.5" dia but are actually 1.75. These are probably the same as the Vac-U-Boat props. Debating whether to use them or not. Trying these cool compression fittings. Going for a direct drive if I can get the alignment perfect enough. If not, there's room for dog bones.
The props were 1.75" in diameter. I wanted 1.5" so what to do? Trim them of course! Rough cut and finished. Before and after.
For general cruising those props should work well and look scale. For combat though, I would definitely go with metal props. There are many times in which during combat a captain may accidentally hit shore or a submerged rock. We've seen plastic props sheer blades by just starting and stopping often.
I hear you on the plastic props. The counter point is that these props are 1/3 the cost of metal ones from Strike or BC (let alone the cast stuff). A rock that could shred plastic could also do a number on the soldered props. These are nylon, stiff and yet flexible so should be somewhat damage resistant. I'll give them a go for a season and see how they do. I've got plenty of spares!
Cast Bronze is the only prop I would put on a boat. When you are going at half speed or no speed the clock ticks very slowly, and 5 minutes feels like a century.
No doubt cast is the strongest but at $30 a prop, the $60 for two is outside my budget on this build right now.
BC props are affordable and a magnitude stronger than plastic. A metal blade is stiff enough to bounce off the rock with little damage yet malleable enough to bend instead of breaking. After the sortie is done, the captain can bend the blade back into place and continue battling for the rest of the day. Well worth the little extra cost.
First shaft gets bonded in. And who needs dog bones? Not this Barham! Set the shaft, then set the mount plate in a bed of epoxy paste and viola! Perfectly aligned motor. Now to the other side.
mechanical fasteners needed to hold motor to hull, all the torque is at that point. JB weld won't hold after it gets hot, but then again plenty of water will be entering in just a second, cooling these down while she settles
LOL! Actually I'm not finished with the mounts. I'll be adding flat head screws run from the inside of the curved mount plate through the outside of the hull. Additionally there will be 1/2" of ply water channeling overlaid around the mounts that will add stiffening and support to the area. The epoxy beds are mainly to provide the alignment.
Carl you've got me thinking. I think I'll get rid of the hose clamp and add a top clamp to hold everything down against the hull snugly.
hose clamp works well but screws are needed, the u clamp is a pain to change motors when you are in a hurry.
Decided to upgrade my motor mounts a bit. It'd be a waste to not use the excellent heat conductive properties of the aluminum motor plates so I incorporated some "heat pipes" to pipe heat overboard. The pipes are made from aluminum cable ferrules that have been counter sunk. Matching dimples in the motor plate ensure good metal to metal contact. Holes are cut in the hull for the pipes to pass through. The 4mm flat head bolts are inset far enough to clear the motor housing. Buttered up with epoxy paste for placement into the hull. After the epoxy hardens over night the bolts are removed and the heat pipes are cut/filed/sanded to the hull profile. A single large or two smaller 1/6" thick aluminum plate/s will be bolted to the pipes for heat dissipation. Two new RS-555PH motors test mounted. When installing the mounts, I was continually adjusting the placement until the shafts turned as freely as possible. Props are high and tight!
"Way over done"? Whats a Tyng build without some unneeded complexity? FYI, the mounts when through bolted are very rigid but they will be reinforced when the water channeling gets bonded around them.
C'mon Ming, show Steve some mercy (yeah, I know...."the Merciless", but still...)...he's not allowed a flux capacitor, so let him go a little crazy on the drivetrain
