ORIGINAL: Deandome
I don't get it; how on earth could drilling SIX holes (or four) in such a small prop be creating something that is safer than a single bolt?
Everything I, and clearly many others, have read is that single bolt hubs are plenty capable at dealing with the torque-loads of engines under 50ccs...and probably more safely, too. I trust OS; they clearly think smaller engines are fine w/one bolt, too.
ZDZ40 also has a 6 bolt prop install. What a royal pita even with a hole drill guide. To me, the props are not as strong when multi holes are drilled in the hubs, but I've never seen nor heard of the wood failing either.....
BME had it right. Their 102 twin cylinder used a single nut to hold 26'-28" props. 10mm shafts are plenty strong enough. OS and SAP have it right currently with single nut installs straight from the factory.
The single nut adapter is great except it's kinda heavy. I looked at the VVRC single nut adapter for my DLE55 about a year ago but realized it weighed more than 2X what the 4 bolts weighed. Single nut set-ups are best made at the factory. On the other hand, if a warbird needs nose weight, it's one quick way to do that
Edit: 4, 5mm bolts weigh around 1 1/2 ounces; the steel single nut adapter around 3 ounces. Extra weight makes a difference in my app. YMMV