Simple Z-Bar front end

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    Dean McGinnes

    Good evening all,

    I am attempting to make a simple front end to put a folding prop on my grandson’s P-30 to convert it to a Mulvihill.

    I am planning to use a Z-bar prop hub for simplicity and lightness. I understand there is a compound angle which will give a good prop fold.

    If memory serves (seldom 🙁 ) the angles are 15 degrees inward and the same backward. I don’t wish to get into a loooonnnng process of calculation, I am looking for a “close enough” solution.

    If he sticks with it, we can invest in Montreal front ends, etc. 🙂

    Am I on the right track ??

    Bill Shailor

    13 and 13 works pretty well from my experience.


    Some people shoot for having the tip of the blade flat against the fuselage side (built-up fuselage). To accomplish this fold, you’ll need to know the tip blade angle then use the same number in the z-bar bend! 13 and 13 would be perfect for a prop with 13 degrees tip angle, 15 and 15 works perfect for props with 15 degree tip angles.

    Don’t forget that to do this type of folding, you have to drill your prop accordingly!!!! Without a good fixture this is sometimes harder than it is worth!!! You might note that famous gumbander Bob White’s Beau Coupe and Twin Fin props didn’t “bother” with it! Just used a flat Z-bar and an easy to drill hole in prop. easy if you remember to drill it before carving the blank which takes away a flat reference plane to use.

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