Early Wooden Propeller. 6 Holes, Chauvier type

[jschoppaul]

Hello,
I bought this at an antique store a few years ago in the states. The owner bought it at an antique store in France in the 70’s.
1) There are NO identifying marks.
2) 6 holes, a distinguishing characteristic.
3) Does appear to have been mounted various times.

Tip to tip 82 1/2” ( 209.55 cm )

Holes appear to be 5/16” ( 0.794 cm )

Hub thickness 3 1/4” ( 8.255 cm )

Shaft hole 2” across ( 5.08 cm )

[pmdec]

Hi,

It is not a Chauvière. Could you post pics of the sides of the hub?

Regards,
Pierre-Michel

[Bob Gardner]

And it doesn't look like a British made prop. The apparent pitch and the diameter of 2095mm suggest a small aircraft with a comparatively low powered engine, I think.

Over to you Dave!

With kind regards,

Bob

[jschoppaul]

Early wooden propeller

Thanks for the replies,
I’ll try to be quick on my end.

[Dbahnson]

And it doesn't look like a British made prop. The apparent pitch and the diameter of 2095mm suggest a small aircraft with a comparatively low powered engine, I think.

Over to you Dave!

With kind regards,

Bob

I don't know what it is either, and I doubt that it can be identified. Note that on the side view it appears to be a solid piece of lumber, unlike most other propellers, which are laminated.

[pmdec]

Hi,

No laminations, no flared side of the central hole and very small bolts... It could be a very very early prop, or, more probably, an amateur construction. Perhaps not for an aircraft.
I don't see how it could be identified... Do you know which wood it is made of?

Has your phone or tablet a built in clinometer? Do you know how to measure the pitch?

Regards,
PM

[jschoppaul]

Early wooden propeller

Hello,
Thanks again for all your help.
1) Yes, it is a solid wood propeller, no laminations.
2) It does look like it was used. There are hub markings from compression, tip damage ( slight ), and leading edge wear.
I tried to measure pitch. Bear with me on my math.
I used to formula of:
PITCH = 2.36 x diameter height / width.

I measured “diameter height” of 1 7/8” or 1.875” at the 75% mark.
I measured the “width” at the 75% mark as 7 3/8”, or 7.375”
So, 2.36 x 1.875 / 7.375 = .6

Does this sound reasonable?

Thanks again for everyone who is trying to help. Even an “age” range would be nice.
John Schoppaul

[Bob Gardner]

Looking at the photographs of the side of the prop shows it be thinner than I expected.

I doubt if we can offer any more help. You might wish to explore photographs of every early aircraft you can find on the internet, starting with the Wright Brothers; and also Google early hand-carved aeroplane propellers. Let us know if you find something.

If your prop is an early hand-carved American or European propeller it is of historical importance.

And I enjoyed looking at your cat. When I was writing my books on British WW1 props about ten years ago, I took illustrative photographs outside in natural light and was always accompanied by one or more of our cats who joined in the process to see what the human tin-opener was doing.

With kind regards,

Bob

[Bob Gardner]

A postscript: you might also wish to find a dendrologist at a local university who would be able to date the wood from the rings, but they would need to bore a hole to obtain a sample.

Bob

[jschoppaul]

pmdec

Hello,
After your comment ( appreciated ), I re-measured the bolt holes.
I was mistaken, they are actually 3/8” ( not the 5/16” I quoted earlier ).

Thanks again everyone.

[pmdec]

Hello,
Thanks again for all your help.
1) Yes, it is a solid wood propeller, no laminations.
2) It does look like it was used. There are hub markings from compression, tip damage ( slight ), and leading edge wear.
I tried to measure pitch. Bear with me on my math.
I used to formula of:
PITCH = 2.36 x diameter height / width.

I measured “diameter height” of 1 7/8” or 1.875” at the 75% mark.
I measured the “width” at the 75% mark as 7 3/8”, or 7.375”
So, 2.36 x 1.875 / 7.375 = .6

Does this sound reasonable?

Thanks again for everyone who is trying to help. Even an “age” range would be nice.
John Schoppaul

Hi, I do think the pitch you measured is (meters):
pi x 0.75 x length x 1.875/7.375, that is 3.14 x 0.75 x 2.10 x 0.25 = 1.25 (= 49.4").

What I have in mind was not measuring the "true" pitch of the prop, but measuring it at different distances, say (from center) at 10, 20, 30 and 40" from the center. If it is a real prop, the pitches have to be quite the same.

Regards,
PM