abufletcher

The trick with the other method is to keep the tabs as short as possible to keep the edge visually clean. The scallop in the test photos doesn't look too bad, but it's not shrinking to the wire so it's not forming a sharp edge.

abufletcher

But, you know, maybe it's good enough. And the clean, scale look not to mention the ease of the heat-shrink method is appealing. Also I notice that I don't have quite as much curve on my CI TEs as on the test piece.

pimmnz

Abu, I have used Koverall and nylon chiffon covering, painted the wire with thinned Balsaloc, trimmed the bottom covering about 1/4" past the wire, then pulled and rolled the covering over the wire and ironed it on. A bit more Balsaloc over the fabric around the wire (letting the Balsaloc dry each time, of course) then do the same with the upper covering. The trimmed edge gets covered with the reinforcing tape either before paint, if its a 'normal' model, or with whatever colour tape (blue, pink, torn lozenge etc) after the lozenge camo colours are applied. The tapes themselves I apply with dope over the straight bits, and Balsaloc again on scalloped trailing edges. all doped over, of course.
Evan, WB #12.

gabriel voisin

Dear Don,
I see you have it done.
It's still not perfect, but a little bit more exercise.

You make one little mistake.
Make the flags shorter, only 5mm on the tissue.
And I use only "Coverite" .....I can sew it.

Tomorrow I'll look for a photo of one of my models at work.

I hope I could help you,....Matz

abufletcher

I'm really torn regarding which method to use. The one-piece/heat-shrink method is easy and more scale...but doesn't work perfectly with solartex. The two-piece/attach-to-wire method described by Evan and Matz (and which I used for my first test) solves the scallop problem but the non-scale "tabs" are visible. Matz is right that I did my test too crudely and that the tabs only need to be maybe 5mm, which would make it look much better.

The other thing to bear in mind on the CI is that I won't be painting the wing (as Evan perhaps did with his model). Paint (not to mention edge tapes) would almost completely hide the tabs around the wire. But on the early CI that I'm modeling the CDL covering was highly translucent (and in fact, I can't see any evidence of edge tapes either, though these could be there). So the tabs, even 5mm ones would be easily visible (and even highlighted by my use of a coffee-laced clearcoat).

gabriel voisin

Abu,
at the original planes all the wire edges was sewn.

There were various methods in Germany to "Eintuchen", depending of the wing design. But never the fabric was in one piece drawn around the edge, because it was not possible.
At the time, the largest width of fabric, was 244 cm and many were placed diagonally, therefore, not possible.

For fabrics with deep "scallops", like on your albatros, at first the tissue was cut in the scallop form.
Then, the lower tissue was drawn around the wire and sutured.
With covers in "Natural", these seams, joints and cover strips were always visible.
Today you see nothing on the replicas , because everything is perfect covered with high tech materials and painted.

For you I've uploaded one small piece of my high-resolution photo.

greetings Matz


There are exceptions, such as the Fokker Dr.1. and the wire has so much tension on the trailing edge that first was sewn a cloth shell.
Then was pulled over the wing, everything sewn and then zelloniert. (Painted with Dope), these machines had only very small scallops.

abufletcher

That's fantastic information, Matz, and exactly what I needed!

gabriel voisin

Don,

itisabsolutely not a problem for me.

Of course, I know it only from the German documents and I have no information how it was done in England or France. But I think it was the same principle.

pimmnz

Abu,
Type in 'The Vintage Aviator Limited' to your browser and see how the full size guys replicate the original methods. These guys do not use 'modern, space age ' materials, they got flax linen made for them. Heck, you could even replicate the proper stiching around the wire...
Evan, WB #12.

abufletcher

I've visited the Vintage Aviator site many times and it's one of my favorites. Their approach to replica building is obviously very authentic. But Matz is right that there are also a lot of replica builders out there who aren't so concerned about original building techniques and materials.

I've striped the covering off my test wing again and will try the "tabs" method again.

allanflowers

After going through the book on Poly Fiber (Stits) coatings, I am convinced one can use the notch method but keep the slits farther away from the edge, and heat work the fabric over the edge avoiding the obvious slits in the final results.
This model is fantastic by the way.

abufletcher

Thanks for the suggestion, Allan. Well, here's the result from a second somewhat more careful attempt with the tabs method. It does produce a nice, sharp edge. But, vtisually it's not so neat and to be honest this is a royal butt-load of work...even on the four bays on my test panel. By the way, I can't possibly imagine being able to edge an edge strip to this using solartex. Possibly I could simulate it with a strip of moistened silkspan, though.

The photos below show the top and bottom on this second attempt. It's better than my first (and I think as good as it's going to get) but it's still not great. So it seems like each method has its pros and cons. The biggest pro of the 1-piece method is that it's EASY. The biggest con (so far) is that I can't get the fabric to pull tight against the wire. The pro of the 2-piece method is the sharp TE and the cons are the intensive effort required and the somewhat ugly tabs (mostly visible on the bottom).

abufletcher

To be truly scale, the rib ends should really be more pointy. But at this scale I felt that would weaken them. It's a compromise I can live with.

By the way, I'd like to try this type of stitching:

http://thevintageaviator.co.nz/proje...g-albatros-dva

gabriel voisin

Hi Don,
I've looked at your photos and I've seen you cut the flags too wide.
As promised, I have uploaded some pictures of my models.
Please have a look on it, I make all things with Coverite and I hope it helps you.

Sorry for the bad picture quality, I've done it with Nokia mobile phone.

greetings Matz

abufletcher

Do you mean TOO WIDE or TOO LONG? I trimmed each of the edges about 5-7mm past the wire and then cut each into 5 strips. If we number them 1, 2, 3, 4, 5, then I folded over 3 first and then 2 and 4, and finally 1 and 5.

Do you mean that I should trim the "tabs" so that they just barely wrap around the wires?

gabriel voisin

I mean to wide. At transparent coverings, do it with more than 5 flags.
Do it with 8 or 10 and make always two flags together firmly on the wire with the iron. But ONLY on the wire and and not shrink.
Then make the upper tissue, pull the flags around the wire, Make it tight on the lower fabric with the iron, only on the wire. (maybe 2 mm more on the tissue)
Now cut all flags, but not more as 5mm long and follow the round contour.
When everything is fixed, then you can sew the edge.
After that step, you can shrunk the top and bottom fabric.

Matz

abufletcher

Here's a test for the German style rib stitching. First I laid down two 3mm strips of solartex on top of each other to keep the fabric from bunching up when the stitch is pulled tight. On the original, a strip is glued directly onto the rib cap before covering and then the fabric is, in essence, sown to this strip. I guess I could do the same and put the reinforcing strips directly on the ribcaps. Then, using a curved needle, a stitch is made across the three layers layers (including the covering), passed back across and under the diagonal thread and then feed through the same hole again for a double stitch. The thread is then pulled diagonally to the next position for the next stitch. Finally, a cap strip is added.

Once I got the hang of it, it wasn't too tedious. I suppose I could finish all the stitching in a couple of evenings. It looks a little "heavy and crude" to me right at the moment. Maybe I shouldn't use a doubled thread as I did here. Also I'll test to see how this looks with my coffee-clear finish. If it looks too course for this scale I'll just give the impression of stitching with some torn strips of solartex. Since I won't be painting the wing I need to be careful about it looks.

gabriel voisin

Now it is perfect, but the german tissue was light linen, unbleached.

abufletcher

Ah, I get it! The tabs are just for pulling and after they are attached to the wire they are trimmed short. Do you pre-coat the wires for better adhesion when attaching the bottom covering? How do you do the wire stitching? Do you have a thin thread that actually wraps around the wire (as I've seen Achim do on his DrI TE) or do you use an "up and down" stitching between the two sides of the fabric on the inside of the wire?

abufletcher

You mentioned in a previous post that the fabric was "zelloniert" which I understand as "coated with cellulose-based dope." From what I've read the Germans used a flax-based fabric that was lighter than Irish linen. But I've also read that the Germans also used varnish as a final coat and that this varnish gave the fabric a bit of a yellowed look (as on the EIII). That's what I'm trying to simulate with the coffee mixed with flat clear. How would you describe the color of a German doped finish?

gabriel voisin

Now you understand it.

I do it differently, but mostly just like in the photo of Otto biplane....with the up and down method.

The technique what you seen, (you know what I mean), its so not right.
Normally, the lower tissue was layed around the wire and sewn. (Such as a bag).
The Upper tissue was pulled to this bag and sewn together.(Up and down technique)
At the DR1 you can produce a complete "condom" and pull it over the wing, the seam is also there at the wire.

greetings

gabriel voisin

"Cellonieren" is actually the name of the method with dope (Spannlack). That comes from the French inventor company Leduc Heitz in 1911.

The French name at Heitz was "Emaillite" andinGermanyof the Dr.Quittner Company: "Cellon Emaillite".

All fabric surfaces of German airplanes were coated with cellulose-acetate lacquer ("celloniert"). Tissue+ stitch+ emaillite = flyable wing.
After the "cellonieren", the aircraft could be painted with oil color. That was not a must, was only for the purpose of disguise or of deterrence.

greetings

Nieuport nut

My Feedback: (10)

I am really enjoying this thread!

Thanks to both Don and Matz.


Martin

abufletcher

How would you describe the color of a "celloniert" only wing? Did it darken the fabric? Did it make it yellowish? Brownish?

gabriel voisin

Martin, enjoy it,...*smile*

Don, I've documents of the German Fliegertruppen, in there isthe describtion.

First is painted with colored pigmented dope.
After that, another 2 coatings with uncolored dope.
Dope is colorless and on the camouflage fabric onlycolorless dope.
The coatings with the first colored dope I know it only on the Fokker triplane.