Found myself a variable propeller and acquired it.
It's not servo controlled, but seems controlled by rpm.
It starts at a setting of 3.5 , and seems to go up to 10". Now guessing what power it can handle, and what engine I'll need to drive it. It's a 14 -3.5/10. Produced by Modelbau Wanitcheck.
Concerning strenght, with manual bending, it seems in the same class as a Master Airscrew.
How does it works ? it seems like two cylinders are forced out, when rpm gets higher, pushing the most forward disc around, this takes along the blades, changing the speed. When the rpm drops, two feathers force the system back. Maybe I'll review the working later
More pics will be posted along, after demount and cleaning .

Does anyone off you have seen or used such thing ?
I would appreciate pics/details of the Mk variable prop as well.
It seems the guy who machined these is still active, we maybe could make a hybrid between the Mk and this one ?