Hello all:

Does somebody knows if the four bladed Rottol propellers used in the Spitfires Mk IX & XVI were wooden or metal made ?

I´m working on a Mk XVI and I want to chip the paint of the spinner and propellers, so I need to know what would show through.

I´ll appreciate your help.

Bit of a difficult question - the XVI (essentially an IX with a packard engine) is mentioned in Shackladys "Spitfire" as having a Rotol 4-blade - no ore info is given. So assuming the blades are the same as the IX then they could be Duralumin, Wood, Hydulignum or composite!

Most references appear to point to Hydulignum or Dural as the main types - but that is just the impression i get from flicking through the book. With that in mind, take your pick .

Hydulignum and Jabroc are wooden composite structures........

Too be blown away by technical comparisons see here -

http://naca.central.cranfield.ac.uk/reports/arc/rm/2357.pdf

Lee

Spitfire Mk VI
Propeller: Rotol 4 blade constant speed, variable pitch, Jablo type R2/4F5/1 (Jablo) or R2/4F5/2 (Dural) 10ft 9ins dia
Spitfire Mk VII
Propeller: Rotol 4 blade constant speed, variable pitch, Hydrulignum
Spitfire MK VIII
Propeller: Rotol 4 blade constant speed, variable pitch type R3/4F5/2 (Dural) or R3/4F5/3 (Dural) or R5/4F5/4 (Jablo or Hydrulignum) (Merlin61 or Type R12/4F5/4 (Jablo or hydrulignum) (Merlin 63 / 63A) 10ft 9ins dia.
Spitfire LMFK VIII
Propeller: Rotol 4 blade constant speed, variable pitch type R12/4F5/4 (Jablo or Hydrulignum) 10ft 9ins dia.
Spitfire HMFK VIII
Propeller: Rotol 4 blade constant speed, variable pitch type R12/4F5/4 (Jablo or Hydrulignum) 10ft 9ins dia.
Spitfire Mk IXb
Propeller: Rotol 4 blade constant speed, variable pitch type R3/4F5/2 (Dural) or R3/4F5/3 (Dural) or R5/4F5/4 (Jablo or Hydrulignum) or Type R12/4F5/4 (Jablo or hydrulignum) all 10ft 9ins dia.
Spitfire MK IXc
Propeller: Rotol 4 blade constant speed, variable pitch type R3/4F5/2 (Dural) or R3/4F5/3 (Dural) or R5/4F5/4 (Jablo or Hydrulignum) or Type R12/4F5/4 (Jablo or hydrulignum) all 10ft 9ins dia..
Spitfire Mk IXe
Propeller: Rotol 4 blade constant speed, variable pitch type R3/4F5/2 (Dural) or R3/4F5/3 (Dural) or R5/4F5/4 (Jablo or Hydrulignum) or Type R12/4F5/4 (Jablo or hydrulignum) all 10ft 9ins dia..
Spitfire LFMk IXb
Propeller: Rotol 4 blade constant speed, variable pitch type R12/4F5/4 (Jablo or hydrulignum) 10ft 9ins dia.
Spitfire HFMk IXc
Propeller: Rotol 4 blade constant speed, variable pitch type R12/4F5/4 (Jablo or hydrulignum) 10ft 9ins dia
Spitfire HFMk IXe
Propeller: Rotol 4 blade constant speed, variable pitch type R12/4F5/4 (Jablo or hydrulignum) 10ft 9ins dia.
Spitfire LFMk XVIc
Propeller: Rotol 4 blade constant speed, variable pitch hydrulignum.
Spitfire LFMK XVIe
Propeller: Rotol 4 blade constant speed, variable pitch hydrulignum.

Hope that some of this will help you Carlos.....

Lee & Jan. Thanks for the info.
Now, what is Hydrulignum ??? Is some kind of alloy ?

No, Hydulignum is 'densified' (compressed) laminated birch wood. Its still used today for a multitude of engineering purposes.

Lee

So as for the info I must assume that if there was some chipped paint, no metal will show through in the prop. blades. Right ?
Another one, ..........what colour must be seen ?

Here is a pic of a hydulignum blade - I cannot say if its from a Spit but it should give you an idea -



Lee

Many thanks for the info fellows.

Any time Carlos....

Something to keep in mind is that on composite props (anything but aluminum (dural) or steel), there is almost always a metal strip formed aound the leading edge of each blade, and on most high horsepower propellers the entire blade is covered in a fabric and resin over the wood. Unless there is major damage you would not often see the wood. I think your best guide for weathering of model propellers is that old standby, photos. If it's a light color, an aluminum color is most likely. The fabric/resin covereed areas that I have seen are all dark. Maybe someone else has direct experience with Spitfire propellers. That was a great list that was put up a few posts ago!

Dural blades were often stained semi-matt black, before being painted matt black. Steel was heat-treated, finely sand-blasted, then sprayed black. Wooden blades were laminations, impregnated with resin, then bonded using tremendous pressure and heat. A fine metal mesh covered that, with a plastic coating over that, which was finally painted black. Any weathering, of metal blades, showed as an anodic grey, not bright silver, and wooden blades simply looked rather more matt, on the leading edges, than usual, with the possibility of a hint of brass, at the tip, from the leading edge sheathing. In the RAF, this effect was not allowed to go very far, before the propellor was sent for repair.
Edgar

This is why this site is fantastic. Thank you guys

Gathering all the info I dicided to show metal through the chipped paint only on the spinner, not on the prop blades.

I´ll post some pics.

Gentlemen:
During WW2, I was stationed at Dum-Dum Aerodrome out side of Calcutta, India. The RAF were our hosts, and the Air transport Command was based their. On one part of the Airflied was a Spitfire overhaul factory. One day I was wondring around the factory facilities and I was approached by the Factory Superintendent. Wanted to know what I was doing. I told I was very interested in the Spit and was curious what they were doing here. Anyhow he took me a conducted tour, Spit disassembly, component repair, engine and propeller overhaul. He showed me a Rotol prop blade that had been cut in two. What I had thought was a steel prop was thin laminations covered with a fine wire mesh soldered on the trailing edge and the leading edge capped with brass. I had never seen wood propeller blades so thin. The mesh was filled with something like bondo and the blade was painted black with a chrome yellow tip. Beautiful workmanship.
Blue Skies,
Dan-San

Gentlemen:
During the visit in the tear down area, I asked the Superintendant how many hours before overhaul, 5000, is what we do? He said the average is 125 hrs! I was astounded! He said RAF Fighter Squadrons are highly mobile, they can move in one day. There is no maintenance, glycol, fuel and ammunition and and occassional tire. There is one tool box to each Flight. All the AMs use a Florin to open the Dzuz fasteners. The Florin was about the size of our quarter. They did not have all the trappings of our Fighter Squadrons with their base facilities.
Blue skies,
Dan-San