General Questions About Biplane Rigging

[Mark_C]

Hello Again,

 

Let me just ask - what are these things, and what purpose do they serve?

 

1)  The double-ended rod-shaped thing that appears to connect the front and rear sets of rigging between the wings.  The rather long one, which appears to be canted so the front end is slightly below the back end, based on other photos I've seen of this airplane.  It looks to me as if the rigging lines/cables somehow run through it.

 

2) Immediately above it, and hanging from the front two cables only is a much shorter apparatus.  I also see another one, which seems almost the size, quite low and close to the fuselage.  What are these for?

 

Thank you in advance for your help.

 

 

[Padubon]

Some biplanes were rigged with flat strips of metal instead of cables. These strips had threads at the ends for turnbuckle attachments. 
The strips produced less drag but due to their shape and flexibility, wind forces acting upon them cause them to make high frequency oscillations, that very likely would tear apart the rigging and as a consequence, the wing arrangement.

To stop the oscillations, a wooden or metal tube/rod was tightly secured the front and rear sets of rigging strips and to secure both sets together.
I have worked on biplanes and it is amazing how rigid the rigging becomes with the rod installation.

Edited December 22, 2019 by Padubon

[Tnarg]

You can see these rods on the Gee Bee racers or the P-26 and the P-26 even has a post from the wing up to the rigging tie rods which must serve to dampen specific oscillations. I think of the tie rods as like guitar or violin strings. They get pushed by the wind and are streamlined to pass through the air, but only if they are oriented correctly. The motion through the air should really get them vibrating and they could resonate like a guitar or violin string if they didn't have some form of dampening.

 

Tnarg

[Mark_C]

Thank you both very much!

[RLWP]

You'll also notice the long rod is positioned where the lift and landing wires cross. The lift wires are doubled and take some of the lifting force from the upper wing down to the fuselage (or stop the wing rising up in flight if you prefer). The landing wire is to stop the wing drooping on the ground and is single

 

The rod is dropped onto the intersection and bound to the wires - that would be the easiest and neatest way to install it too. That way it will stop the lift and landing wires from rubbing against each other in flight

 

I was hoping my 'Aeronautical Engineering' published by Odhams Press* might have a diagram, unfortunately not. It does tell you how to take the wing off a Beaufighter though...

 

Richard

 

*The more mature UK readers will be aware of Odhams publications - technical stuff published in the 1950s aimed at people who know nothing containing a lot of fascinating yet usually worthless information. Mine cost me £1 at a car boot

 

 

Edited December 23, 2019 by RLWP

[jimbo]

Great info. Aren’t these called “batons”?
 

jimbo

[RLWP]

1 hour ago, jimbo said:

Great info. Aren’t these called “batons”?
 

jimbo

 

I have just cut carrots into batons for Christmas dinner

[jimbo]

15 minutes ago, RLWP said:

 

I have just cut carrots into batons for Christmas dinner

Ha, “rigging” the Christmas dinner with vegetables LOL!

 

j

[RLWP]

10 minutes ago, Jennings Heilig said:

On a lot of airplanes the batons have openings through which the wires pass, so they’re not just “sitting” on the wires.  On the real thing, they’re made in two halves and screwed together (so you don’t have to run the wires through the holes). I’ve never figured out a way to do that on a scale model.

 

And even more complicated still, like the bizarre ones on a SPAD VII or XIII.

 

From the photo, the floatplane does seem to have the batons on top of the wires, if only at the front

 

Richard

[Mark_C]

12 hours ago, RLWP said:

 

And even more complicated still, like the bizarre ones on a SPAD VII or XIII.

 

From the photo, the floatplane does seem to have the batons on top of the wires, if only at the front

 

Richard

 

I was able to find a photo of the F6C at Pensacola, and it has good views of the batons:

 

https://www.flickr.com/photos/elaref/38054909002

 

The wires appear to go through the batons here.  This aircraft is sometimes listed as a "replica," so I don't know how accurate it is.

[RLWP]

I'd say this mostly shows assuming that the general applies to the specific can lead to mistakes. My interest is in early aeroplanes where what I described is often true, clearly not in this case

 

Nothing beats a good photo of what you are modelling!

 

Richard

Edited December 26, 2019 by RLWP

[mozart]

1 hour ago, RLWP said:

I'd say this mostly shows assuming that the general applies to the specific can lead to mistakes. My interest is in early aeroplanes where what I described is often true, clearly not in this case

 

Nothing beats a good photo of what you are modelling!

 

Richard

As always, check your sources and never assume!