Plywood surfaces of upper sides of Myrskys wings are ground and painted with undercoat paint

Suomeksi

When the lower sides of VL Myrsky II’s (MY-14) wings had been painted at the Tuesday Club with undercoat paint, the wings were turned around and the undercoat painting of the upper sides was started.

The procedure follows the undercoat painting of the lower sides of the wings. First the plywood surfaces are painted with Tikkurila Oy pale grey TEMALAC AB 70 alkyd paint which contains aluminium flakes, using fine rollers. The flake paint is used to make the plywood surface very smooth. The aluminium flake alkyd paint is covered with a layer of TEKNOS Oy adhesion primer Futura 3. The wing surfaces are painted with several layers of both paint types and after each layer the surface is ground smooth with sandpaper. The adhesion primer has a darker shade of grey than the alkyd paint, so that it can be seen when the lighter grey layer of alkyd paint becomes visible when the adhesion primer surface is honed.

Before starting with the aluminium flake alkyd paint, a couple of plywood seams were spackled on the upper side of the wing. Then the plywood surfaces were ground as smooth as possible. A disk grinder was used, with 180 grinding paper grit. The disk grinder also removed the grinding dust. After this the plywood surfaces were vacuumed and wiped with an alcohol solution which removes grease. The solution contained 50% Sinol and 50% water. Then the damp surfaces were dried with a heat blower. Then the grinding was repeated, now manually and using 240 sandpaper grit. Then the surfaces were cleaned again.

Photo: Jouni Ripatti.

Photo: Jouni Ripatti.

Photo: Jouni Ripatti.

Photo: Jouni Ripatti.

The aluminium flake alkyd paint was applied on the upper sides of the Myrsky’s wings with mohair rollers. In spite of this the paint surface quality wasn’t acceptable – it had some uneven “orange peel surface” parts. Therefore the first layer of paint was carefully manually ground smooth. The surfaces were painted again, this time with aluminium flake paint, thinned to 80%. This is how the desired quality of the painted surface was reached. The upper sides of the wings will be painted with another layer of TEMALAC aluminium flake undercoat paint before the Teknos Futura 3 adhesive primer is applied.

Photos: Lassi Karivalo except when separately otherwise mentioned.

Translation: Erja Reinikainen.