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Early propellers were made from wood and they still are on some vintage/classic aircraft and reproductions. What types of wood are typically used to make wooden propellers?

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Historically, the following woods were used:

  • Mahogany
  • Walnut
  • Oak

Almost all wooden propellers are reinforced to add strength. Fabric or metal coverings can be added too.

enter image description here

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    $\begingroup$ What do you mean by "reinforced"? Do you mean by materials other than wood? $\endgroup$ – Sander Dec 10 '14 at 8:37
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    $\begingroup$ @Sander The URL I referenced mentioned that, the entire section at the bottom. I didn't include that here because it was verbose and not directly relevant to the question. $\endgroup$ – Farhan Dec 10 '14 at 17:13
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    $\begingroup$ Metal pieces like the one shown have a dual purpose. In addition to reinforcement, it protects the leading edge of the blade from damage when hitting birds, sand or gravel on runway, etc. $\endgroup$ – brichins Dec 10 '14 at 20:37
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Propellers should be made from the same type of wood as wing spars: In both cases the requirements are the same, and the wood should have the highest strength to mass ratio. Both need to be light and strong, especially in tension in the case of propellers. Using a dense wood will increase the inertial loads, so nordic spruce (wood from higher latitudes grows more slowly and has better strength) is a good material. There is no need to make both from the same material, however, and historically a wide variety of materials has been used.

Equally important is the glueing from laminated planks and shaping. The craftsmen at the worlds first propeller company, Chauvière, were first in the business of making toilet seats. Switching to propellers came naturally. Laminating helps to control the density of the wood planks and makes it easier to cut out imperfections, so laminated propellers are better balanced and will be 25% lighter because less allowance has to be made to account for imperfections.

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    $\begingroup$ Best of Aviation.se: "first in the business of making toilet seats. Switching to propellers came naturally" $\endgroup$ – rbp Dec 9 '14 at 23:07
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    $\begingroup$ Is it really that important for toilet seats to be that strong??? My goodness, what are you people doing to them? $\endgroup$ – Lnafziger Dec 10 '14 at 4:23
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    $\begingroup$ Key reason for laminating: wood will bend as it dries / absorbs moisture. By cutting it and re-assembling with directions reversed, you can effectively prevent this. So not only does it make the wood stronger (by criss crossing the main direction of the wood you make the strength isotropic; and you prevent crack propagation because there are no "preferred directions" any more), but you also preserve the shape which is very important for efficiency of the propeller. Edge "reinforcement" is there just for erosion control (dust, gravel, etc). $\endgroup$ – Floris Dec 11 '14 at 12:18
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    $\begingroup$ @Floris all agreed except for the isotropic part, which is not relevant for propellers. You want anisotropic strength and stiffness, i.e. all fibres more or less radial to counter the predominant loading. Which is just why wood with its strong anisotropy is (still) such a good material. $\endgroup$ – yankeekilo Dec 11 '14 at 14:45
  • $\begingroup$ @yankeekilo - the point is that you have control over the degree of anisotropy by changing the orientation (and layering). You may want more strength in one direction than another - and bias the lamination accordingly. At any rate, even a small fraction of cross fibers will reduce the chance of the wood splitting. $\endgroup$ – Floris Dec 11 '14 at 14:48
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Wooden propellers can be made of virtually any wood, I know Sensenich makes theirs of birch, and the company featured on this episode of "How It's Made" apparently uses maple.

I would assume that hardwoods (birch, maple, oak, etc.) are favored over something like pine or spruce that would be easily dented in operation if the propeller kicks up rocks on the ground, though I can't find a good reference on that.

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    $\begingroup$ I doubt lignum vitae would be a good choice though, makes the nose even heavier than it is already. $\endgroup$ – ratchet freak Dec 9 '14 at 21:20
  • $\begingroup$ @ratchetfreak Pusher prop? :-) It'd be pretty durable that's for sure! $\endgroup$ – voretaq7 Dec 9 '14 at 22:31
  • $\begingroup$ The prop should have brass plating in impact areas, so spruce is no disadvantage. Birch is good for lowly-loaded props, and maple a good choice for props with higher loading. $\endgroup$ – Peter Kämpf Dec 10 '14 at 20:57
  • $\begingroup$ @PeterKämpf Sensenich apparently uses urethane in place of traditional brass bindings for the same purpose on at least some of their props - the inexorable march of progress I suppose :) $\endgroup$ – voretaq7 Dec 10 '14 at 22:04
  • $\begingroup$ wood-database.com $\endgroup$ – yankeekilo Dec 11 '14 at 14:40
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Birch, maple, oak, mahogany or walnut are good choices.

Wing spar material is usually sitka spruce which is too soft for propellers.

I would not sit on a sitka toilet seat either as the slivers from it are toxic.

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