McCauley/Whirlwind Props

[Steve W]

This message is directed towards Whee and its discussion may be of benefit to others. Was wondering how you made out with finding a suitable McCauley hub and getting the blades installed at Whirlwind? I'm not even sure you did it or not but was following it on another forum. I am really interested in building a prop like this. I had a discussion with
Jermie at Whirlwind and this is still a doable avenue for a CS prop.

[whee]

I never went through with it for two reasons: I didn't buy the airplane that had the prop I was looking to change, which is the main reason. The second reason is after further study of propellor harmonics I determined that I wasn't comfortable using a experimental composite prop. Composite props suffer the same vibration issues that metal props do unless they have some form of internal damping.

I have talked to WW a couple times and they can fit their blades to modern McCauley hubs. The blades are retained in the hubs by tung and groove; sometimes the groove is in the blade and the tung in the hub and sometimes it is the other way around. You can either send them your Mac hub and they will make and fit blades but the lead time is like 10 weeks. Or you can tell them if your hub has the grooves or the toung and they'll make the blades. Once they have the blades done you can pull your prop down a send them the hub. Turn around time is still several weeks. More recently I asked about a prop for my Continental and they said they didn't have a hub for it. If I sent them a hub, in my case a C203, they would install their blades on it. The hub I was going to use on the Lyc O360 was a C214.

[Steve W]

Hi Whee.
Thanks for the update. Have been in the bush the last few days.
From what I understand, the damaging harmonics from the composite prop is extremely less destructive than metal props mainly due to the weight and the material absorbing the vibration. This is more so in the composite over wood blades. Having a composite blade in hub that is rated for an aluminum blade should, and I repeat should be bullet proof. That's kind of where my train of thought is right now unless I learn something different.
I have an I0-360-C1D6 for my Patrol which is counter weighted which will add that much more absorption for harmonics.The engine came with a three bladed Hartzell prop and I was hoping WW would have blades to fit. Like you said, the only hub they can re-blade is the McCauley.