The surface treatment of Snoopy?s fuselage framework

Suomeksi

The fuselage framework of the experimental aircraft OH-XEA “Snoopy”, currently being restored  by the Tuesday Club of Aviation Museum Society Finland, was without its fabric covering when the Society received its ownership. When and why the fabric covering had been stripped off, is not known. Anyway, Snoopy had been stored without its covering for a long time, as its fuselage framework, welded of 13 mm steel tube, was in such thick rust.

The first stage of restoring the fuselage framework was to clean it from rust. Cleaning the steel tubes until clear metal appears is however unnecessary, as removing the superficial rust will suffice. When the tube surface feels very smooth to your fingers, it is clean enough. For the purpose, we used sandpapers of various grades as well as scrubber sponge. The grinding dust was wiped away carefully with rags of fabric and solution mixed of Sinol spirits and water.

Not grinding the fuselage framework until clear metal shows is because for priming the tubes for their surface paint, we use the clear Isotrol lacquer (Klarlack Grund). This lacquer penetrates through possible rust to the surface of the tube, stopping the rusting process. The surface can then be painted directly on the lacquer.

After the whole fuselage framework was cleaned from surface rust, we then treated it by a thin coat of Isotrol, covering fully the steel tubes and other metal parts and giving the tubes a nice shiny surface.

After the lacquer had dried, the fuselage framework was painted with Isoqaurd Panzer, an alkyd oil paint for metal. Originally in the 1960’s, the fuselage framework had been painted with red Ferrex anti-rust paint, still visible as residues in the tubes. Simulating the red Ferrex, the Isoquard paint was tuned to the same tone of red. An exception was the landing gear that was painted with black Isoquard, according to its original black paint.

The fuselage framework surface treatment is now done.  The restoration work of Snoopy’s fuselage will next proceed with the cockpit, as well as measures priming the fabric covering of the fuselage.

Photos by Lassi Karivalo.

Translation by Hannu Mononen.