I think the major reason that they want you to run a wood prop is the vibration dampening ability of the wood. Reciprocating engines inherently create power pulses, instead of a nice steady power output like, say, a jet turbine or electric motor.
You have this mass of a propellor up front that has a certain inertia to it, and when the power pulses are transferred, that prop tries to resist... This creates a torsional stress (a fatigue stress at that), and if it gets bad enough for enough time, it will break something (usually the crank). The wood prop tends to dampen these pulses out (not to mention the inertia of the wood prop is USUALLY less than that of a composite or metal one). If you want to run a composite or metal prop (read something other than wood) then you really "should" have a dampener of some kind in the system.... Type IV rear drive units sold by GPASC come with an elastomeric dampener, and a lot of gear reduction drives have some kind of dampener built in. In general, it's not a good idea to run anything other than a wooden prop on an undamped direct drive setup... (unless of course the crank is designed with that fatigue cycle in mind) Matt --- Colin & Bev Rainey <crain...@cfl.rr.com> wrote: > I have read for several years about only running wooden props > with VW direct drive. Alittle research shows that the main > reason was the crankshaft failures near the keyway on the tip > of the crankshaft wear the hub is. The Force One hub was > designed to prevent this type of failure. If I have a Force > One, then I should be able to run any prop I want since this > is designed to eliminate the breakage problem at the snout of > crank. I would like to run a ground adjustable Warp Drive > prop. > > Colin & Beverly Rainey > Apex Lending, Inc. > www.eloan2004cr.com > crai...@apexlending.com > 407-323-6960 > _______________________________________ > Search the KRnet Archives at > http://www.maddyhome.com/krsrch/index.jsp > to UNsubscribe from KRnet, send a message to > krnet-le...@mylist.net > please see other KRnet info at http://www.krnet.org/info.html > ===== ------------------------------------------------- Matthew Elder Orangeburg, SC http://www.infinigral.com/melder
