There was a mistake gluing gussets to the trailing edge of the aileron. It is no summer anymore and temperature in my shop is around 15-16 degrees C. with humidity around 40-50%. L20 Epoxy in the summer has to be mixed according to the mixing table and left alone for 1 hour (that’s different temperature and humidity in summer). Then is has to be applied and left to soak for 15’. During this time cotton wool flakes has to be mixed into the epoxy. The mistake was, that I took too much cotton flakes (it has to be one teaspoon to 100 g of mixture) and I did not accounted for the low humidity and low temperature in my shop.

Next morning my gussets came off with gentle pull. You can see this in the pictures. Today I have made a “green house” with electric heater for my aileron and properly mixed epoxy with cotton flakes.

In general, it takes 70 g of Epoxy mixture to glue all the aileron’s gussets