The CAD work on the licence built Hispano-Suiza 8F (Wright-Martin H3) is complete. The model has been made as per the aircraft version of the engine, but with some marine conversion parts added. The most notable and visible of those being the water cooled exhausts.
In addition to the exhausts I’ve also taken the liberty of moving the water pump from directly under the rear of the engine to the back. All of the marine conversions that I’ve seen have moved the water pump to somewhere else. I assume it’s to allow the engine to be mounted several inches lower in the boat, and so improve the C of G of the installation. I’ve also opted to keep the magneto driven ignition system at this point, though I may also draw up a more modern installation too eventually.
One area still to be resolved is the marine transfer gearbox. I intend to use the engine kit in future boat models and so have drawn up a notional modern style gearbox for those installations. I will also produce a period gearbox, but am waiting on some research information to do that.
With the CAD model virtually complete I’ve been in contact with a number of 3D Printing Bureaux to get prices and leadtimes, but in the current pandemic I assume they will be pretty heavily committed to work combating that.
In the interim I have been printing the parts out on my own entry level machine. It can be a bit temperamental, is very slow and the quality of the output isn’t good enough for the finished model, but… It does allow me to check the parts and how they go together before I spend real money getting them done professionally. A number of mods have been incorporated into the model as a result of this already.
It will also provide me with a rough prototype of the model that I can use as a buck for making parts to, and so minimise handling of the proper model. I also intend to use it to design the mountings in the actual boat.
Hopefully this rather techie phase will be over soon and I can get back to real physical model making.