A propeller for the Snoopy's engine

Suomeksi

The Aviation Museum Society’s donation, the OH-XEA Snoopy experimental aircraft, was without its Continental A 65 engine and the propeller. As far as we know, the engine and propeller had been given away, after the Snoopy’s flying days were over.

Photo by Esko Keskinen.

The problem of the missing Continental A 65 engine was solved when we were donated a damaged Continental engine of a plane that had crashed. It’s not airworthy, but it needn’t be, because the Snoopy won’t be restored to flying status. We’ll restore the engine looking complete and make the exhaust pipes, looking like those that were in the Snoopy’s Continental engine.

Photo by Juha Veijalainen.

We were also lucky about the missing propeller. We were donated a slightly damaged and struck off propeller, fitting the Continental A 65 engine. The wooden propeller is made by the German Hoffman Rosenheim works in 1986. One propeller tip is damaged. It’s both broken and has a dent in the leading edge.

The division between the six fastening bolts was exactly the same as in the propeller hub of the Continental A 65. The holes were, however, slightly smaller, so we drilled the holes with a column drilling machine to respond the to the fastening bolts of our Continental engine propeller hub. The compatibility was tested by fastening the propeller to the hub.

Because the propeller is mainly white, it doesn’t correspond to the Snoopy’s propeller in appearance. The Snoopy’s propeller tips were red. At the bottom of the red area there was a narrow white stripe. Otherwise the propeller frontside was blueish grey or the same colour as the aircraft itself. The backside of the propeller was, however, painted black between the white stripe and the hub.

We’ll repair and restore the propeller’s outer appearance like it was in the Snoopy. That’s why the markings and tapes were sanded off the surface of the donated propeller and anyway the propeller’s surface was rebuffed for the painting.

The crack in the other propeller tip and the dent in the leading edge had to be fixed before painting. We ended up fixing the tip crack with epoxy glue. So the crack was immersed in epoxy glue, after which it was pressed tight between two plastic plates with clamps. When the clamps were taken off after the glue had dried, the crack was well closed and the propeller tip was sanded smooth.

The dent in the propeller’s brass leading edge was first tried to straighten and then file smoother, but the metal turned out to be too hard to shape. So we decided to spackle the dent full with Lightweight Epoxy Filler. When the filler had been spread over the dent, the dent was covered with a plastic mould, shaped similar to the profile of the propeller leading edge. The mould was pressed with clamps to the leading edge.

After the filler had dried, the mould was taken off. It was noticed then that part of the filler hadn’t adhered properly to the dented area, but had come off with the mould. So we spackled the unsatisfactory part again, after which the leading edge dent became universally smooth. The propeller repairs had been accomplished and the priming of the propeller could be started.

Before starting the priming, the surfaces of the propeller were once more buffed lightly with sanding paper. The buffing dust was first wiped off with a dry cloth and finally with soft cloth immersed in a 50%/50% mixture of Sinol /water. The priming was done with a paint brush. As the paint, we had the same blue greyish Isotrol oil-based paint, that we used in painting the Snoopy’s wings, horizontal stabilizer and elevator plywood patches. The shade is the same blue greyish colour that was used on the Snoopy’s original surfaces. The priming will clearly show if the propeller surface will need any additional spackling. After the paint had dried out it was noticed that no more additional spackling or sanding was needed before the painting of the propeller to the scheme used in the Snoopys propeller.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation to English by Matti Liuskallio.