Tracing Lozenge

['14-'18aviationcollector]

Originally Posted by MicroSculpt

David:

Your tracings of the Knowlton airframe would be valuable in developing a map of how the aiframe was covered. Similar to those in the Albatros Publication's Fokker D.VII Anthologies. I don't have those publications at hand at the moment. I do recall a brief article on the Knowlton sample — but I can't recall if there was a drawing based on the lozenge layout. I think not.
Tom

I have been meaning to respond to this for some time, but I have become side tracked, and I was just looking through this thread again and I would like you to clarify this please.

When you say David, do you mean me? I assume that you do, but the research I have relates to the Albatros D.Va and the Pfalz D.XII, not the Knowlton Fokker D.VII. I have tracings of many pieces of the D.XII in particular. When you mention a map of how the airframe was covered, do you mean a scale drawing showing exactly which piece of lozenge fabric goes where, which way it was placed, where the seams were located, and other details of this nature? I have never seen the Fokker D.XII Anthologies, so I can't compare the information I have with what is printed in that publication. I suspect that what I have described is what you are referring to, and I have actually done that.

I drew the layout in 1:48 scale about 15 years ago, but I lost interest in this because my full size tracings don't necessarily make a lot of sense without a full sized original or replica frame to lay them over, or a set of good drawings from which I could construct a replica set of wings. There are many little features which were visible on the fabric, and which were easily traced and photographed, but they don't make a lot of sense unless you can work out exactly where on the airframe these particular features were located. Anyone who has done any work with lozenge fabric will know what I mean. It can be easy to get confused. There are any number of factors which can complicate the process such as the fact that some batches were different widths to others for some reason, and that each aeroplane was covered with a unique pattern, in the same way as I have mentioned previously that every Fokker Dr.1 had a different streaky camouflage pattern. It is very easy to go cross eyed and to get more than a bit frustrated when you are trying to work this pattern out, and to work out how it is all applied to the airframe. Given good enough photos, each individual aeroplane should be able to be identified by its' unique pattern, but as we all know, finding photos in the sufficient quantity and of sufficient quality is often (but not always) difficult, if not impossible. As we all know, the Knowlton Fokker D.VII is an absolute goldmine of information, and mapping the unique pattern of this aeroplane would be relatively easy, given the number of photos available of this aeroplane.

There have been many interesting questions raised in this thread, and it would be very nice to see some more of them answered. I do have the 1:48 scale drawing in my collection, but I have not seen it for some time. I suspect that I made a few mistakes in the drawing, some areas are extremely difficult to work out, and others I had no data for at all. Some areas I only had access to photos of, and not the original piece to trace.

Cheers, David.

[MicroSculpt]

David:

OOPS, my mistake. I thought you had the Knowlton tracings as well.

I think a "map" of the Albatros and Pfalz coverings would be very interesting and informative. It would add to the knowledge base of the subject. Especially since there are few examples of airframes with the original coverings.

I hope there will be some sort of article from the AWM team on the D.V coverings at a later date. A "map" as well. I did come across this verbal description from the team on another site that I thought contained some very interesting points:

The finish of the upper wing at the time of capture, December 1917

The upper wing is one-piece, and has a light framed structure with ribs. Just to the right of the centre-line it has a large rectangular well to accommodate the engine radiator and its louvre system. The two ailerons are of steel tube construction. The timber wing structure was prepared for covering by securing narrow linen strips to the bottom and top of each rib and in several other locations. The strips were in fact a woven tube which was about 7 mm wide when flattened. They were not glued down, but were secured with stitches and, additionally in some areas, nails. As far as we have been able to establish, the stitching of the strips is very similar to that found and described from the NASM Albatros. Further strips of fabric, all of five colour lozenge in either the upper or lower surface variety, were glued down to the timber structure at various points. These additional strips were probably intended to protect the main covering from sharp edges etc. Many were very small - less than 10 mm wide - and irregular in width and were clearly hand cut.

The main covering of the wing was made up of two large sewn panels of linen fabric, one for the top surface and one for the bottom.

The top panel was assembled from eight sections of plain un-printed linen, sewn together with seams oriented to run parallel to the ribs (‘chordwise’). Six of these sections were about 1250 – 1270 mm wide, and two were located at the tips and were narrower at about 500 mm wide. The seams were carefully spaced so that they did not lie on top of a rib.

The lower surface panel was a mainly a single span-wise piece – over 9 metres long - of lozenge printed fabric of the five colour lower surface type. It was a little too narrow to cover the chord width, so an 120 mm wide strip of lozenge was attached with a sewn seam along the long side closest to the trailing edge of the wing.

The lower panel was applied to the wing first, and at the leading edge wrapped right over to the top surface for about 50-70 mm. It was unevenly trimmed off and secured down to the ply skin in this area. The original width of the five colour main panel is hard to judge accurately, but must have been at least 1450 mm in total. The top surface fabric came next. At the leading edge it was sewn down along the centre-line to make a neat horizontal seam. At the trailing edge the top fabric was wrapped over to the lower surface, sewn in position and trimmed back to about a 10 mm overlap.

After the main covering was secured by nails and stitching, it was reinforced with more machine made fabric tapes. On the upper surface, there were plain 10 mm tapes along each rib. On the lower surface, a combination of 7 and 10 mm tapes of a dyed purple colour were used. The 10 mm was applied to most ribs; the 7 mm size was apparently used only on the ribs adjacent to the radiator. Further 30 mm wide purple tapes were used to seal the leading and trailing edges and a few other areas. It is worth noting that there was apparently a system of tapes employed on this aircraft, with a special narrow one for a special purpose. The entire surface of the wing was finished in clear dope.

Both original coverings for the ailerons are missing, but photographs show that the left one had printed fabric on the lower surface that matched the adjoining wing fabric. The right aileron had visible lozenge fabric top and bottom, and the covering panels are believed to have been the five colour upper and lower surface versions respectively. The method of applying the fabric is believed to be same as that for the the elevator, which is of similar construction.

The upper surface of the wing, including the left aileron, was painted with purple and green camouflage colours before capture. The lower surface remained clear-doped. The demarcation between the upper surface colours was a sprayed edge, blending from one shade to another over about 20-30 mm. These lines were not completely straight, and were slightly angled so that the trailing edge end lay to the left of the starting point at the leading edge. The lines were located roughly between Ribs 6 and 7 on the left side, and Ribs 5 and 6 on the right. The sequence of colours, from left to right, was green/purple/green. The horizontal demarcation on the leading edge was not particularly sharp, but was fairly level rather than wavy.

Metal fittings, including the strut attachment brackets and the radiator, were painted in the medium grey-green finish. The maltese crosses at the upper wing tips conformed with official dimensions, and each consisted of a black cross 1400 mm square with a 50 mm wide outline all around, giving an overall dimension of 1500 x 1500 mm.

The only other known markings were of a technical nature, and included the four digits of the aircraft serial number on the ailerons. Little clear detail of these markings has been found, but they are faintly visible in some photographs.

A substantial amount of the 1917 fabric covering of the upper wing has been examined, but quite a lot is badly damaged and some parts were removed during early AWM repair work. Some areas have been patched and re-doped using British materials. The later solvents and dope have penetrated the under-lying German layers. The surfaces have also been varnished and partially over-painted at various times.

The good news is that the full chord width survives at the centre and continues for about a 1-2 metres outboard on each side. Continuous fabric across the entire span is also present. This means that the widths and placement of the major sections can be determined. Many smaller details have also survived. The general location of the upper surface paint colours can be confirmed from the fabric, but the exact placement and dimensions of the demarcations is currently based on photographs and study of similar paintwork on the lower wings.

Pretty thorough. Huh?

I'm not sure, even with all the photos of the Knowlton D.VII, that it could be easily mapped just from photos. But I agree that it would be a valuable and interesting endeavor to map it and compare it with the application methods illustrated in the Anthologies. In particular it would provide evidence as to whether there was an effort to orient the panels to a specific method of application.

Cheers!

Tom

['14-'18aviationcollector]

Originally Posted by MicroSculpt

David:

OOPS, my mistake. I thought you had the Knowlton tracings as well.

I think a "map" of the Albatros and Pfalz coverings would be very interesting and informative. It would add to the knowledge base of the subject. Especially since there are few examples of airframes with the original coverings.

I hope there will be some sort of article from the AWM team on the D.V coverings at a later date. A "map" as well. I did come across this verbal description from the team on another site that I thought contained some very interesting points:



Pretty thorough. Huh?

I'm not sure, even with all the photos of the Knowlton D.VII, that it could be easily mapped just from photos. But I agree that it would be a valuable and interesting endeavor to map it and compare it with the application methods illustrated in the Anthologies. In particular it would provide evidence as to whether there was an effort to orient the panels to a specific method of application.

Cheers!

Tom

That's ok Tom! I wish that I did have tracings of the Knowlton Fokker D.VII. It is a fascinating aeroplane, and one of the very few which retains its' original fabric (well most of it at least). I will see what I can do with the maps of the Albatros and Pfalz. It has been my intention to do these for quite a while. I spent many years compiling the information, but I found it to be a difficult and incredibly time consuming task. It is also easy to make mistakes, and as I have pointed out many times, my tracings don't always make sense, because for example there are some distinct (although at times subtle) markings, outlines of fittings and other features which really don't make any sense (to me at least) in the absence of a decent set of drawings, or a structure to lay the drawings onto. I do have some drawings, but I don't know how good they are, and I certainly don't have any space to start building anything. I am currently negotiating some hanger space and hopefully some workshop space with two land owners in particular, and I certainly don't have a shortage of willing volunteers to help me to construct some parts. There are no promises that either of these negotiated sites will become available, so I am limited to my lounge room floor, at least for the moment. I certainly do not have any intention of constructing a full sized set of wings at home, I just do not have any space whatsoever to keep such a structure. If hanger space is granted, that could be a different story.

Yes Tom that is a very thorough and informative description. I can assure you that yes there was a conscious effort to orient the panels to a specific method of application. There were however some exceptions to the rules, and I noticed on one of my tracings that there were for example, two panels which were laid the same way, ie. they did not alternate direction, as was usually the case, and every other panel (I am going from memory here but I am fairly certain) alternated in direction, when compared to the panel on each side of it. I put that down to wartime conditions in the factory, and as I have stated, lozenge really was applied quite roughly. Dan-San said the same thing IIRC, and it is true. It was generally fairly roughly applied, and was often pulled at awkward angles. Further, the dope must have added to the distortion. The pulling at angles is not excessive, but it certainly is noticeable if you look closely enough, and if you know what you are looking at and are looking for.

Cheers, David.

[Dan_San_Abbott]

'14-'18 aviationcollector:
Yes Ross sells the fabric, I am not sure of the price per yard, I think it is around $50.00/yard. He has it printed in linen, Grade A cotton and one of the synthetics aircraft fabrics. You can e-mail Ross at, ross@avcloth.com
His telephone number is: 502-349-1429, Fax 502-349-1428. He has tapes, waxed cord, etc.
When I finished working on the five color pattern, I checked a few points on the NASM pattern in the Albatros book. They are fairly close.
Blue skies,
Dan-San

['14-'18aviationcollector]

Thanks for the reply Dan-San.

I had been meaning to reply to this for a while, but it had slipped my mind because this thread had dropped off the list when I pressed the Forum button. You know how it is, sometimes there are many issues being discussed, and some threads disappear temporarily. There doesn't seem to be much being discussed at the moment and I found this in the camouflage and marking section.

$50 / yard is very reasonable, and I might actually purchase some of this fabric. I think it would be very useful as a reference, and to see how the colours and pattern compare to the samples I have seen. When you say that the pattern you developed was fairly close to the pattern printed in the NASM book, how close was it? The pattern in the NASM book is close to the pattern I posted the photos of, but it is clear to see that there are differences. Presumably the pattern you developed is closer to the pattern printed in the NASM book than the pattern I posted the photos of. Is this correct? If I purchase some samples of the fabric I will be able to see for myself, but for the moment I would be very interested to hear your comments, if your research work is readily accessible.

Thanks Dan-San. Best wishes, David.