I do - it is false. I called them to ask about a batch of pylon props I received with very badly located through-holes, i.e. off-center enough I could spot it at arm's length. They do not balance props before shipping, nor do they drill the hole at the CG. The recesses in the hub are molded and absolutely on center. But the holes are post-drilled, and APC admitted to me on the telephone that the process is subject to error.

To perfectly center an APC prop a bushing is needed, but one that centers in the molded recess in the rear of the hub, NOT one that derives it's indexing from the drilled hole, or else you are back where you started. Or else you need to balance them by centering the balancer shaft on the through-hole, not pinned by the cones - no guarantee the cones are concentric with the through-hole.

I admit I am a fanatic about balancing - many of them run reasonably true off the shelf ( "reasonably" and "many" are the key words here, they are much different than "very" and "always"! ). Thousands of people use them that way. Then again my engines run really smoothly and don't shake the crap out of the airplane and everything attached to or contained within it.

MJD
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Good info!

I did notice that the electric props have the inserts for smaller shafts and ensure things are centered as well.

somegeek