Hi, Yvon....I went to the hangar to try to find the Sensenich specs for
proper bolt torque, but Hurricane Ivan had blown the hangar doors in, and
apparantly blew the instructions into the next county.
     I asked the Canard Aviators group the same question, and I received
several different answers, but most all of the replies have things in common
such as:
     The torque values are dependent upon how many laminates the prop has.
Multi-laminate props such as Performance Propeller will tolerate and require
higher torque numbers than props with only 8 or 10 laminates.
     Also, the thickness of the hub can alter the torque requirements. (7
inch hub versus 6 inch hub)
     There are other variables, such as the hardness and type of wood and
glue used, etc.  25 ft lbs seemed to be a good ballpark figure from which to
start, but if your prop is multi-laminated, it will go up to as much as 35
ft lbs.
     Almost all who replied stated that it is important to adhere to the
recommendations of the manufacturer of the prop, because of the many
variables that could effect proper bolt torque.
      I hope some of this information is helpful. Attached is a Word
document from Hertzler propellers covering their torque recommendations, as
well as an informative article covering the proper care, balancing, and
repair of a wooden prop.  Sorry for the delay in responding....it took me a
little time to inquire and get responses from others, especially Mr.
Hertzler, who manufactures wood props. Take care,  Paul Conner

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