Questions about mounting a composite prop spinner

by Brad Kunkel

Sep 25

I have a Sensenich prop spinner that I'm modifying to use between a gear reduction unit and an IVO prop hub. I was initially advised to get a UHS spinner but it appears that they are out of business.

1. Can the spinner backplate bulkhead be mounted between the metal gear reduction and prop hubs and be torqued down without damaging the composite?  I've never worked with this material before.

2.  The predrilled holes in the bulkhead are around 5/8", way bigger than the AN6 bolts in the hub.  Are there bushings that I need in order to reduce the hole size and perfectly center on the hub?  Even if this spinner bulkhead were mounted with a Sensenich prop, it looks like bushings or something else would be necessary.  

Thanks,

Brad Kunkel

  • up

    John Austin

    Just speaking from personal experience, I would say the answer is "yes" to both your questions.  I have a Sensenich carbon fiber spinner (and prop) and the backplate is also carbon fiber and bolts between the engine's prop flange and the prop hub without damage.  My spinner backplate also has oversize holes (oversize for the prop bolts) to accommodate the aluminum drive bushings that are inserted from behind the engine's prop flange, through the backplate and insert into the prop hub, keeping everything aligned and centered.

    I have found Sensenich very helpful with support (however, all discussions were with all-Sensenich components).  In the past, they have supplied me with a custom prop spacer and over-length prop bushing material that I could cut-down to the proper length since I needed slightly longer bushings with the spacer - and at very reasonable prices, I might add!  The Sensenich plant in Florida is the one to contact for both the wood and composite props and composite spinners and support.  Don Rowell is the manager there and also provides technical support.

    John

    N750A

    1

    Sep 26