Fabric covering of Caudron C.59 wings is being patched
Sunnuntai 12.9.2021 - Tuesday Club member
When the Tuesday Club activities were interrupted because of the Covid-19 pandemic in March 2020, the holes and tears on the fabric covering of the lower wings of Caudron C.59 (CA-50) were being patched. The damages on the lower port wing had already been patched. The tears on the fabric covering of the starboard wing had already been sewn and the patches had been cut from linen fabric, they were waiting to be glued with shrinking varnish. There are plenty of holes to be patched on the covering of the lower wings, about 50 on both surfaces.
Now the Tuesday Club can continue its activities again and the Caudron’s starboard wing is underway again. First the surfaces of the fabric-covered lower wing were vacuumed and the wiped with a damp cloth. Then the correct patch had to be found for each hole on the lower wing. Fortunately the holes and the patches had been numbered, so the pairing was easy. During the 18-month break the patches had been carefully stored and none were missing.
Each patch was placed on its matching hole. Then a protecting circle was taped around each patch so that the gluing varnish will not spread outside the patched area.
When all the patch areas had been surrounded with tape, nitrocellulose varnish (shrinking dope) was spread on the area inside the tape circle. The edges of each patch had been unravelled and the patches were pressed on the wet varnish. More varnish was applied on each patch so that the fabric and the unravelled edges became thoroughly wet. The unravelled edge will make the edges of the patch fasten better on the original fabric covering. This was the work method when the fabric covering was patched in the 1920s and 1930s.
The protecting tape was removed soon after the varnishing so that the glue of the tape won’t harden on the fabric surface. If the tape is left on the painted surface of the fabric covering for a long time, it is possible that the tape will leave a mark on the painted surface when it is removed.
When the varnish had dried, the patches had shrunk nicely on the holes and damaged areas. The surfaces of the fabric patches and their unravelled edges were ground smooth using a fine grinding pad. The patches will be varnished and ground at least a second time so that the surface becomes very smooth before it is painted. The patched areas will be painted greyish green to match the hue of the Caudron’s wing surfaces, which have been painted in the 1920s and gained patina during the decades.
Photos: Lassi Karivalo
Translation: Erja Reinikainen.