I mentioned in my last post on the Miss Severn build that I had been filling the time between sanding sessions developing some CAD projects for possible later builds. Here are a few CAD renderings of the models just to give you and idea of what’s been going on at MBIQ Mansions.
Hispano-Suiza 8Ab 180hp direct drive.
This is one of the early versions of this engine. 11.8L and 180hp. It looks very similar to the Wright-Martin H3 engine that I have already featured on this blog, but is actually quite a bit smaller. The Wright-Martin was a licence build of the H-S 8F and was enlarged to 18L and 300hp.
Hispano-Suiza 8Be , 220hp reduction gearbox drive.
The next is an Hispano-Suiza 8Be which developed 220hp and was one of the last developments of the 11.8L version of this engine. It achieved the extra power by increased compression and higher RPM. In order to keep propeller speeds down the unit was fitted with 0.75:1 reduction gearbox. This was a bit of an achilles heel of these engines as the gearbox was prone to failure and there were several instances of the gearbox and propeller leaving the aircraft before the pilot had finished using them.
Post war the engine featured in a number of racing boats following another marine conversion by Auto Engine Works of St. Paul, Minn. The conversion included updating the magnetos with coil ignition and replacing the reduction gearbox with a bespoke unit featuring a reverse gear. I am developing a converted model as time on the Miss Severn build allows.
Wolseley Viper 4.A*. 200hp Direct Drive
The next model is a Wolseley Viper 4A*. This engine developed 200hp and was directly driven, thus avoiding the problems of the later H-S 8. The design was a licence build of the Hispano-Suiza 8 engine, but many improvements were introduced during the process and the engine is different from the original version in quite a few areas if you start looking closely.
Le Rhone 9C, 80hp Rotary
The final model I’ve been working on is the Rhone 9C engine. Sometimes known as the 80hp Rhone to distinguish it from the later 9J which developed 110hp. The engine was fitted to a number of aircraft, including the Sopwith Pup which is where my interest comes in. I have a long term aim to build a 1:8 Sopwith Pup to go with my Hasegawa Camel model and this will be a key part of it. The work on the main engine is complete, but I haven’t drawn any of the ancillaries yet.*
* Update: The CAD model of the engine is now complete, as you may have deduced from the opening image on this post.
So, those are some of the background projects bubbling along. All have been designed to be built at 1:8 scale as that is my preferred format. When or whether they will ever appear on here as builds is anyone’s guess!