We continued a little with the spoilers. My idea about the linkage is that the best linkage is not linkage, so what we did is use a magnet to close the blade, and the same servo with a modiffied arm push up the blade. To retract the servo move down the arm and the gravity, the wind when the sailplane is flying and the magnet at the end close the blade...
I used this system before on my E-BOT and work flawless..., so this is what I did is to follow the principle of KISS;
( Keep simple stupid...)
We glued a magnet to the inner face of the blade, close to the center and also build a little tray for a screw. You can turn the screw and this way it is possible to accurate adjust the heigh of the blade to close flush with the wing surface.
The magnet hold the blade so strong that you can put the wing inverted and doesn´t open, but still have a light pressure to not overload the servo...
In this video you can see how works this aproach on my BOT....
The little delay between one and other blade at closing when the plane is flying doesn´t exist cause the wind slipstream flow equal on both blades and close at the same time the two spoilers.