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Biplane Scratch build construction

#1
I decided to start building a depron biplane using the known flitetest build techniques. searching the internet on how to construct a biplane the right way, I found several differtent aspects to be important:

size and angle of the horizontal stabilizer
angle of main wings
angle of thrust
getting the cg right
Airfoil

The cg seemed to be the easyest to get right. One needs to make sure that all weight is located as far in the front als possible. In addition, adjust the length of the nose to get the balance right.

Angle of thrust seems to depend on how main wing and h. stabilizer are built and how the motor is located between the two wings. In most models the plane needs a few degrees of down thrust, since the lower wing is closer to the motor.

The angle of attack is what is puzzeling me the most. The way I understand it is, that one can have differtent angles on the main wings to soften the stall tendencies. Preferably the wing with the ailerons needs to have less aoa than the other wing, so it will still have enough airflow if the other wing already stalls, right?

Asuming, the upper wing has the ailerons, is it best to give this wing a neutral position (angle) and the lower wing a positive position or should both wings be positive (leading edge pointing up)?

If I change the angle of the horizontal stabilizer to a positive angle to counter the lift of the main wings and to get the tail up, the aoa of the main wings will change als well during flight. So, if there is a positive aoa on the main wings the angle may get more neutral in flight.

All in all, there are quite a few aspects one may consider. But what is important? What can be neglected for an average parkflyer? What needs to be done?

Would like to learn from your experiences.

Tnx,
Pero