Question about WWI fabric coverings

[BiggTim]

Was the dyed fabric coverings on WWI planes translucent? I know that doped plain linen certainly let a lot of light through, and painted linen tended to become pretty opaque with successive layers of paint, but what about the dyed fabrics, such as the German lozenge patterns? How much light got through those?

 

Tim

[D.B. Andrus]

Good question, Tim.

 

Cheers,

Damian

[thierry laurent]

The reproduction of a lozange camo fabric I had in my hands many years ago looked very opaque even if, in full scale, things may appear to be very different. Nonetheless, I'm remembering that if it was quite common to see the wings markings through a doped linen wing the same was not applicable when the fabric was dyed.

[BiggTim]

1 hour ago, thierry laurent said:

The reproduction of a lozange camo fabric I had in my hands many years ago looked very opaque even if, in full scale, things may appear to be very different. Nonetheless, I'm remembering that if it was quite common to see the wings markings through a doped linen wing the same was not applicable when the fabric was dyed.

I'm very curious if anyone has pics of the inside of a cockpit or through a wing that might show how much comes through. If it does, I think it would be fun to emulate that on the fuselage sides around the cockpit, and I have a couple of ideas on how to do it. I used to do something similar in architectural modeling to represent stained glass using vellum. 

[BiggTim]

I found a couple of pics that demonstrate the question. The first shows a reproduction D.VII where the painted labels on the outside of the fuse and a small amount lof light are visible on the left from inside the cockpit, suggesting at least some translucent properties of this repro fabric in sunlight.

The second shows a period fuselage side up against a piece of fabric with very distinct stripes, yet the stripes are not visible through the old fabric at all, suggesting almost no translucency without backlighting, even with things places directly against the linen. 

The third is another period swatch sandwiched in plexiglas. It also shows none of the background through it, even in a well lit room. I would love to see the other side of this piece to see if the markings are visible.

 

I think these pics only muddy the waters. I still don't see a clear answer.

 

Edited November 28, 2022 by BiggTim

[thierry laurent]

Actually, this is logical from a physics perspective. Adding varnish on a white tissue allows light to go through it because the liquid is clear and filling the small gaps in the weave. Do the same with dark colored paint and this is the opposite. With regard to dyed fabric, this depends how tight is the weave of the fabric. But the ones made for covering wings were very tight. And, last, that essentially depends on the sun light strength. At noon in the middle of the summer, there is no doubt the probability to see top markings or wing stringers was far higher than under a cloudy winter sky!

[LSP_K2]

Aviattic makes both interior and exterior lozenge, with the interior lozenge being lightened specifically to show the translucent effect of viewing the lozenge from the back side.

[thierry laurent]

50 minutes ago, LSP_K2 said:

Aviattic makes both interior and exterior lozenge, with the interior lozenge being lightened specifically to show the translucent effect of viewing the lozenge from the back side.

Indeed.  This makes sense because in that case light is going through one single fabric coat whereas wings have the top and bottom ones.

[jeroen_R90S]

I took this photo on a very sunny day at La Ferte Alais airshow a few months ago.

The effect is less noticable on the wings, though. Not this aircraft may have clear dope on it, and not brown varnish as was often done, at least according to the WNW instructions.

 

Note you can see the "Kuhlerklappe" stencil on the inside of the fabric. I think it was in the WNW instructions but I've seen cockpit photo's from this aircraft on the inside where you can see the weight table stencilled on the outside through the inside. Noto also the oil and fuel stains in the fabric are already less transparent but the angle isn't great for that (I just liked the effect and took a picture )

 

I also have photo's of this aircraft on cloudy days and then the effect is not there. Really depends on the weather and angle of the sun I guess -and also, this aircraft is kept really clean. If this stuff is brown varnished and covered in oil, fuel and dirt I guess it's not all that translucent any more...

 

Jeroen

 

[BiggTim]

7 hours ago, jeroen_R90S said:

 

I took this photo on a very sunny day at La Ferte Alais airshow a few months ago.

The effect is less noticable on the wings, though. Not this aircraft may have clear dope on it, and not brown varnish as was often done, at least according to the WNW instructions.

 

Note you can see the "Kuhlerklappe" stencil on the inside of the fabric. I think it was in the WNW instructions but I've seen cockpit photo's from this aircraft on the inside where you can see the weight table stencilled on the outside through the inside. Noto also the oil and fuel stains in the fabric are already less transparent but the angle isn't great for that (I just liked the effect and took a picture )

 

I also have photo's of this aircraft on cloudy days and then the effect is not there. Really depends on the weather and angle of the sun I guess -and also, this aircraft is kept really clean. If this stuff is brown varnished and covered in oil, fuel and dirt I guess it's not all that translucent any more...

 

Jeroen

 

A perfect example, thank you! I've seen interior shots of this bird, as well, but none from the outside.

 

As far as Aviattic's decals, I was aware of the two different interior/exterior shades, but I thought it might be fun to try actually making it slightly translucent at the cockpit, kind of like the old balsa & tissue models I used to make. I may never actually do it, since it would require the use of a separate frame and skin, but we'll see. 

Edited November 30, 2022 by BiggTim

[LSP_Mike]

WNW took this into consideration with their DVII kits. A few modellers have pulled off the CDL look with respect to sunlight showing structure of wings.

Good point regarding the color change of varnish due to photosynthesis.

[Oldbaldguy]

Everyone refers to the lozenge camo as dyed fabric but I wonder if this is true.  Dying fabric is a difficult and time consuming process.  I cannot imagine trying to dye long runs of yard goods in this specific hard-edged pattern made up of so many colors.  I would think the colors were silk screened onto the fabric much like designs and logos are silk screened onto modern tee shirts.  That would certainly be cheaper and much, much quicker.  The result would be a single coat of pigmented material forced into the weave of the fabric, making the pattern visible on both sides although the “top” side would be sharper than the underside.  The thinner the coat, the more light passes through.  I’ve never bothered to check, but I assume the pattern repeats?

[europapete]

yes it does.