View Full Version : Info about a hub?

02-09-2016, 01:31 PM
I picked this clock up at a local thrift store. I got it for the Chelsea Clock mounted in the hub. I originally thought it was a car clock, but after some research I figured out that it was an airplane clock dated December, 1917. That's when I realized that it was mounted in a propeller hub, and not some random chunk of wood (it's obvious to me now, but I didn't see it that way at first...)

I know that you're not supposed to cut up old wooden propellers to mount a clock, and before anyone chastises me about it, let me make it clear that I found it this way at a thrift store, I don't know who did it, and whoever did it has likely been deceased for years. Thanks for your patience...

Anyway I'm a clock guy. I took the clock apart and cleaned/oiled it and it's now in tip top running condition. But I don't know much about propellers. From what I've been able to find online, this is a Curtiss hub that fits an OX-5 engine (8 bolt holes, Center Bore is 2.67", Bolt Size is 0.375", Bolt Circle is 5.25" and hub thickness is 4") I'm guessing that it's a piece of an old Curtiss JN4C propeller. I ruled out the Hartzell Liberty Signal Corps Prop because the font on the numbers stamped on this hub more closely match what's on the Curtiss props.

It's stamped with the following: 1, X11, and 2; (and at the very top there looks to be the letter "X" cut off where the propeller was sawed through). Given the indentation and wrench marks, I believe this was actually used on a plane. I think it's made of mahogany, but I guess it could also be walnut, it's hard to tell through the varnish; either way it's heavy...

The cap nuts are likely original (again, just my guess) given the slightly yellow tint to the nickel plating on them.

All that said, Does the research above sound right, and is there anything else I should know about it? Also, any idea of the value? I know the value of the clock by itself, but no idea how to value the hub, or the whole thing. Thanks in advance for your time and information!

02-09-2016, 05:02 PM
My thoughts:

1. It's likely for an OX5, as you guessed, but the likelihood of it fitted to a JN4 is much, much lower. There were a lot of planes that used an OX5 engine.

2. The "1" and "2" are simple blade markings to differentiate them, since otherwise they look identical. The "X" was often used to designate "experimental", and there were lots of experimental props made and destroyed in the development process.

3. The circle around the bolt holes are "witness marks" that indicate the presence of a pressure at one time, which confirms the likelihood of it being mounted on an aircraft or a testing machine.

4. I don't think that the cap nuts are original. I think basic hub design always included standard nuts, since you would not want any limit imposed to their torque when being tightened to adjust to wood shrinkage.

5. The hub is not very "valuable" for much other than holding the clock. I would almost consider it disposable, since I think finding a buyer would be difficult.

02-09-2016, 05:17 PM
Thanks so much for the information! Your insights make perfect sense to me, especially the cap nuts comment. I had no idea that the "x" meant experimental.

I was afraid that a cut down and modified hub like this would have little value, but the clock itself is collectible, so not a total loss.

Thanks again