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MrSunu
10-16-2015, 06:23 PM
Hi everyone,
I am trying to identify the following propeller. There are no number left on the hub. I am interested in the potential makers would could have manufactured that one. Its height is a 160cm and the Hub diameter is 15cm.
Attached a couple of pictures.

Thanks for the help!

Dbahnson
10-16-2015, 08:39 PM
No decal, no numbers, and no hub - all (unfortunately) make accurate identification nearly impossible.

Bob Gardner
10-17-2015, 06:16 AM
It is related to Jakes's propeller blade in the thread below.

It dates from the late 1930s to the late 1940's, is probably British and is one of three or four blades on a hub which allowed the pitch to be varied from fine to coarse.

I've copied this description below from my reply to Jakes. which describes the manufacturing process;

These propellers were the next generation of the laminated wooden propellers used during WW1. Your prop blade is an early example of the use of composites, which were far stronger than laminated propellers. The process was called Hydulignum. Google should give you a detailed description.

In outline, several thin laminations of birch were compressed at a high temperature and pressure whilst immersed in resin. It had a black coating which was a resin-soaked cloth stocking slid over the blade and covered with a rubber sheath. The blade was then compressed under pressure in resin at 80 deg F for twenty minutes by which time the stocking and rubber sheath had become part and parcel of the blade. It was a superb almost indestructible coating.

The value of yours has been reduced by removal of the original black sheath but the appearance has been improved! If you polish it every few months with pure bees wax the appearance will improve considerably and the wood will be preserved.


The shaft of the blade, now missing, had a steel sleeve where the drawing number identified which aircraft it was for.

With kind regards,

Bob

MrSunu
10-19-2015, 03:23 AM
Thank you for your replies, I know I had very little information.

MrSunu
10-19-2015, 08:05 AM
Bob,
I was wondering then, based on your comment from Jake's thread and some more research on the web, is it likely to be a Rotol manufactured blade? I mean before they became Dowty rotol i guess.

Alex