by Mick Cherry
This is the 1/6th scale Kinner Radial, there is one in 1/4 scale but my lathe is too small for that size. This engine is by Mr David Johnson and he did the design while he was an engineering student.
You must excuse the cylinders being held in by sticky tape, it was just a way of holding it together for the picture.
This engine looks too simple to be a scale radial with it’s heritage in the 1920’s. However, but when you read about Bert Kinner he was aiming for simplicity.
Winfield Bertrum “Bert” Kinner imagined that if he could produce aircraft cheaply enough they would be as common as the family car. In 1926 the new Air Commerce Act required licensing of both pilots and mechanics, restricting this futuristic plan. Nevertheless, the 1930s “Golden Age” of aviation was ready for Kinner’s improved and less costly aircraft and engines. There were a lot of “ups and downs” along the way. During several months of 1925 Bert Kinner was too ill to work, and a thief broke into his hangar stealing all of his tools and spare parts. Bert Kinner and Kinner Airport in East Los Angeles were out of business — but not for long. Although he was physically ill, Bert Kinner had an unsuppressed healthy imagination. During recuperation, he focused on designing an air-cooled, five-cylinder radial engine.Bert Kinner: The Ups and Downs, AviationPros
These are views which show the general set up. I thought I would include a picture of the crankcase. This was a nice thing to make, plenty of different set-ups and a few fixtures to make with the rotary table earning it’s keep.
You will see in the pictures of the assembled crankcase that it has a dull finish. The reason for this is quite simple. I would not have thought that in the 1920s these engines would have been highly polished, so all I am trying to achieve is the appearance of a casting.
by Mick Cherry
The crankcase for the Kinner is a work of art in it’s own right.
Ken goes into the detail of machining the crankcase. Starting with a 120mm diameter billet that is 50mm thick and then the removal of 90% of the material.
The carburetor is a delight to see in steps.
As with most of us model engine makers Ken makes a lot of jigs and tools along the way. A good example of this is sensitive drill press.