husafreak

My Feedback: (3)

Just stuck a Xoar 16x6 on my YS110. I'm using a Dubro prop nut. Do i need to put a washer between the prop nut and the prop or is the prop nut supposed to go right up against the prop?

dmccormick001

I assume you're talking about one of the aluminum spinner prop nuts that Dubro sells. I never use one of those as an actual prop nut, I always secure the prop with a regular prop washer and nut combo, and then put the Dubro in top of that, using the Dubro part as sort of a jamb nut. I don't think they intend for you to use only the Dubro nut, since there isn't anything to lock the nut onto the prop, washer or not. Just substitute the Dubro nut for the outer jamb nut that comes with most engines. Just my opinion.

David

krayzc-RCU

My Feedback: (31)

let us know how u like that prop.....

husafreak

My Feedback: (3)

So I need a jam nut, thanks but that is going to look pretty silly. Guess I'll end up with a spinner or just hand prop it!!

dmccormick001

You need a jamb nut no matter what kind of spinner you choose to use. Only one nut, whether it's just a simple hex nut with a washer under it, or even the larger spinner-type nut like the Dubro, is just asking for a prop to come off in flight because of the rotation of the prop. As the prop bites the air, the drag is causing the prop to resist the effort of the motor to turn it, which can result in loosening of the nut. Not to mention if the engine happens to backfire, it will spin the nut (and prop) right off. That's why engine makers include a two-nut system (allright you guys, wipe those smiles off your faces) that lock the prop in place by jambing them together. And a wooden prop is more likely to cause problems, because as it gets some age on it, the wood tends to compress a bit and can cause it to loosen a lot. If you fly a wooden prop, get in the habit of checking it to make sure it's tight fairly often. Like I said before, in my opinion, to use just the Dubro nut is a mistake, I'd use it as the second or jamb nut. I have several planes with that arrangement, and I don't think they look silly. Good thing is, you have a solid, rugged spinner to push your starter motor on to that won't get scuffed up by the starter cone slipping, and they don't ever crack and come apart like the plastic spinners. How it looks will depend on the type and size of the plane.

David