I am trying to balance a 11X3.8 SF APC prop using a magnetic balancer.

The prop will rest at either 2 or 10 oclock position randomly ( either blade can be at the top) . This the prop in its original condition with no attempt made to balance it yet. What does this mean? Is the hub unbalanced? Is this good enough ?

Normally I would balance the prop so it stops randomly at all clock positions but this stopping at 2 or 10 oclock is new to me so I not sure how to proceed.

Tks

With an 11 inch prop that sounds good enough. At any clock position is correct but an 11 inch prop it isn't that big of a deal.

I found the problem. The two cones did not grip the prop properly ( hub too thin) so there was some prop wobble. I reversed one of the cones so that the prop is sandwiched on one side with a cone for centering and the other side with a flat surface . Now thew prop behaves like it should .

On any brand balancer that uses two pointed cones on a balance wire when the hub is so thin that the pointed ends touch in the middle. One cone should be reversed so its large back end rests aginst the face of the hub and the second cone with the pointed end inside the hub does not interfere with the first cone.

John

I found this with every APC W-Wide prop. They have a very narrow center section. It's often a problem getting mounted tight on an engine too.

Good discovery TK.

Just learned something new - means it's a good day. Thx.

When I ran into this problem I just ground down the points of the cones so they would not touch.

Tacx that is fine if you never use engines with smaller shaft sizes say .20 and under or some electic props where the smallest taper of the cones is needed. Just turning one around is easy and just as effective Well that is untill your cone/wire set is so old and well used the cones slide to easily [X(]

John