Wooden Pitch Propeller

[dtchacos]

Hi everyone,

I happen to have purchased 2 wooden pitch propellers that i would like to identify off which plane / engine it came off.

Any help is greatly appreciated.

Thanks in advance

Dee

https://drive.google.com/file/d/152F...ew?usp=sharing

https://drive.google.com/file/d/1rrV...ew?usp=sharing

https://drive.google.com/file/d/1_90...ew?usp=sharing

[Dbahnson]

There are many, many possibilities and not enough information in those photos to tell.

I would suggest contacting Monte Chase at notplanejane.com for any help with variable pitch propellers.

[dtchacos]

Hi Dbahnson,

Thanks for the suggestion, i have sent them an email but meanwhile thought you could give me some hints of what further details are needed to have them ready when asked.

Hub size ? diameter ?, number of bolting holes ?, bolt hole sizes ? , propeller length is measured from up till the hub ?, width is variable depending on which part is required and so on, i am not an expert as i dont the criteria it depends on in detail.

Thanks

[Dbahnson]

I think that the stamped numbers may be all that he needs. If you know the manufacturer that's also usually helpful, along with photos of the blades.

[dtchacos]

Hi

I have managed to clean up a bit the hub to see the numbers stamped on it if that is of any help, attached some pictures, What do you think ?

[Dbahnson]

Still, contact Monte Chase.

[Bob Gardner]

It is a beautiful example of a prop made before or during WW2 by the Hordern-Richmond Company of Great Britain where Dashwood Lang was the prop designer.

The prop is made by the Hydulignum process, devised in Germany. It is the first example of what is now known as Composites. As can be seen, it comprises laminations of wood, often birch or beech.

Hydulignum comprises non-impregnated, densified wood laminates developed especially for a wide range of industrial applications. Selected beech veneers are kiln dried to a given moisture content, cut and assembled into packs with a film of synthetic resin coating the individual veneers. The packs are then subjected to extreme pressure and temperature, causing them to be bonded to form laminated boards.

The prop in this photograph has lost its protective coat, which is a cotton sheath pulled onto the blade and soaked with synthetic resin and again subjected to extreme pressure and temperature. It forms a very effective protective coat which is extremely difficult to remove, often impossible.

With kind regards,

Bob

[Bob Gardner]

The prop was made by Rotol. The part number RA100 62 RA indicates that it was a blade from a three bladed prop used on the Hercules aero-engine Mks VI and XVII, which powered the Vickers Wellington bomber, Marks XI, XII, XIII, XIV.

With kind regards,

Bob Gardner

[JR44]

Interesting as it didn't look laminated in the traditional sense.

[pmdec]

.../...
The prop is made by the Hydulignum process, devised in Germany. It is the first example of what is now known as Composites. As can be seen, it comprises laminations of wood, often birch or beech.
.../...

Hi Bob,

Very intesting! Do you know what is the difference with Micarta and Permali processes? Permali looks very similar (see attached pic), but the making process is perhaps different?

Best regards,
PM

[Bob Gardner]

Bonjour mon Ami. In 1954 the Hordern-Richmond Co merged with Permali. I am currently trying to find the name of the German Co who were unwise enough to sell the process to an English Company in the years leading up to WW2.

[Bob Gardner]

In 1954 Permali Limited purchased Hordern-Richmond Limited, both companies were manufacturers of densified wood laminates and Bakelized products, Permali under the trade names Permali and Dialam. Hordern-Richmond were manufacturers of Hydulignum wood laminates and other products.

In 1956 a new Permali factory at Gloucester was opened. This factory brought together the various manufacturing processes within the Permali group, which included Hordern-Richmond, Ltd., Hydulignum-Jabroc, Ltd., and Jabroc, Ltd., under the trade names Permali, Permawood,Hydulignum and Jabroc, together with "Dialam" Bakelized paper bushings and Permaglass glass-fibre laminates.
Permali companies in the UK were still trading in 2013 and probably still are today.

As new composite material technologies were developed and as older technologies were replaced, there have been a number of new companies formed as a result of corporate restructuring, mergers and acquisitions. Permali Gloucester Limited now concentrates on composite materials using glass and aramid fibres, and used in defence and medical markets, and is privately owned following a management buy-out in 1998.

Permali Deho Limited is owned by a German company, and continues to make laminated wood composites. Mekufa UK Limited
manufactures epoxy insulation products used mainly in electrical engineering applications.

[pmdec]

Hi,

Bob, thank you very much for these infos. The Ratier prop I showed was from 1938. It seems it was the first of this kind made by Ratier. There was some others between this one and 1944, essentially in 1939 and 1940.

Regards,
PM

[Bob Gardner]

Bonjour Pierre-Michel,

Did Ratier make props for Les Boches from 1940 until 1944?

With kind regards,

Bob

[pmdec]

Hi Bob,

Very soon after Germans entered in Paris in June 1940, the Ratier factory was under command of German officers. And yes, I think the factory made prop for Lüftwaffe aircraft and for French ones used by the Germans. We have very few archives for this era because it seems Germans took them and we don't know if they were destroyed or if they are somewhere.
We have just the prop registers where prop destination are written but without knowing if they were trully made nor, if they were made, how much of them.

From people who have worked there in this era, there was many "errors" during fabrication process... In Figeac factory, which stand not a very long time in "free zone", it was the same and there was a bombing by La Résistance in 1944 (see joined pic).

Regards,
PM