We use special technology for strengthened the spars in the models.
To achieve most strength we prepare plates of carbon with special epoxies.
Carbon fibre is a micro pipe. That's why it is necessary to use special solvents for epoxy to saturate carbon fibre better.
We make longerons in the special molds by the temperature of 150C and for this purpose we use epoxies that are used in aero-space technologies.
We create pressure to the carbon by screws and in addition silicon expands and create pressure of 30-50 Bar (Pic.2).

A ready plates we glue to the balsa of vertical direction with epoxy L-285.
We wind around the longeron with the kevlar thread to improve reliability.
We make carbon pipe for the wing joiner than polish it with the sandpaper, glue into the longeron and wind around with the kevlar thread.

We reinforce every balsa rib with carbon to improve reliability.
The trailing edges is a thin piece of carbon fiber for rigidity and strength.