Wet Blending of 3 Colors on Fokker Dr.1's

[Welsh Dave]

Taz- I'll be in touch.

On such relevant samples as have so far been discovered, there was blue tinted dope on the undersides, clear dope on upper and side surfaces.

I'd say it's possible that the F.I machines had tinted dope overall, but there is only anecdotal evidence to suggest that. I wouldn't bet on it.

On production machines, it wouldn't do to vary the weight too much, and tinted dope would be heavier than clear. The blue on the uppersurfaces of 588 and another Dr.I for which I have a British capture report but as yet no identification, was, I think, more probably the underside paint with added clear varnish to make it translucent like the regular streak paint, and similar in density.

We can only speculate on the reason for using underside paint that way, but it was apparently done, and on a considerable proportion of aircraft if the presence of two reports out of a small total is anything to go by.

Alternatively, perhaps one of the uppersurface paints used a blue dye rather than olive.

[Welsh Dave]

Hi, Sreiko.

Yes, streaky camo carried straight through onto the D.VII.

The only D.VII sample we have is from 368/18, and it has a paint that is pure bright green where it has been brushed out onto the pale fabric, plus a darker shade of the same green. As it is overpainted in Jasta 18's white and the sample is small in any case, the full range cannot be determined; the dark grey mentioned by Karl Timm and now available as a sample from DR.I 144/17 may have been used for the darkest streaks.

It is impossible to know whether the pure green replaced the olive green before or after the end of Triplane production, or indeed if they alternated or were used together at some point. Small samples, remember.The Bill of Materials for the Dr.I does not specify a shade for the aniline dye, only a quantity.

Now, as we have two distinct colour samples from 144/17, a dark grey and an olive greenish brown (or vice versa), it follows that colouration was left to the paint shop staff, who presumably used whatever was available.

The amount of dye by weight was important in working out ordering for the production run, the colours less so. Some historians have said that colouring materials were in short supply, so it should not be surprising if different coloured dyes were obtained, as long as they could be used to make camouflage paint.

Incidentally, I find it rather offensive to contemporary observers who used terms such as "scumble" (an oil painting technique) and "wash" to suggest that they were not "trained in color". The generation so tragically depleted in WW 1 was at least as well educated as we today, and much better in many cases, particularly in the arts.

[RAGIII]

Originally Posted by Taz

RAGIII- I was about to answer your query, but glad to see you found what you wanted. Dave Roberts, Dan-San Abbott, and Manfred Thiemeyer have the most experience with actual samples of Dr.I fabric and their knowledge eventually adds up to a very close appriximation of how a Dr.I was finished. Alan Toelle offers the most scientific analysis of the samples he has examined. As Dave says, the green streaking turned brown over 90 years or so and this explains Dan-San's Methuen references, which are, I believe, too brown. Dave's theory that a dark gray was the dark streaks is plausible. Manfred has the whole picture if he decides to enlighten us. He has had more access to WW-I pilots, fabric samples, etc than anyone because he has been interviewing WW-I participants for over four decades. Any information we get from him is invaluable.

Taz
Terry Phillips

Attachment 8257

Taz, thanks for the picture. I can't argue about the return evident in the photo. That being said if Daves statements and documentation of the undersurface Blue tinted Dope are examined in conjunction with the field observation of the crash.could a WET Blending of green and blue still show the return of the Blue undersurface? I am just not prepared to discount that report totally, 90 years later. I find the existence of another sample showing Dark Grey to be interesting in that Acer mentioned 3 pigments in that previous thread. considering the size of the samples it seems although not probable, combinations such as mentioned in the fokker Anthology can not be wholly discounted. Like you, I wish your friend would share his knowledge.
I know most of us would love to catergorize everything as being Black and White but it seems that discoveries continue to be made, even in locations long thought to be searched thoroughly! I never thought another DR1 streaking thread would shed new light on the subject but you and Dave certainly have made this interesting... AGAIN
RAGIII

[Welsh Dave]

It appears that 588/17 was painted in the usual way, except that some form of blue was used on the top and sides in place of the lighter shade of olive. It would, no doubt, be wet blended.

The underside would then be painted, again as usual, with a returned edge.

[ManfredT]

Welsh Dave,

was there really a need for a white PIGMENT like zinc oxide (or rutil titanium, or basic lead carbonate) for the upper surface of a Fokker Triplane when the fabric was nearly white and a translucent effect was wanted? Are you sure that the white spots you observed was "blooming" zinc oxide? An analysis would be welcome, even for a better protection of the assets in the IWM.

The aniline dyes were brillant, but in 1917 most of them were NOT stable, only the very expensive one, and it is very doubtful that Anthony Fokker used them, when we are looking at the surviving samples of fabric.

acer

PS I like the Juanita Franzi interpretation

[Welsh Dave]

acer - I take your point, but the darker streaks on the IWM sample, those now erupting in spots, are not as translucent as the lighter areas. You can't see the fabric weave through them. If the paint had no body, the weave would be visible throughout, and it isn't. Besides, the paint needed some pigment content to perform its role of protecting the fabric from ultra-violet light. Translucent was the watchword, not transparent.

Last year there were cloudy patches in the darker streaks, and now there are tiny white spots. On the transparent window there are corresponding dark olive spots where the dyed varnish medium has stuck and come away from the presumed zinc oxide. That is the only white pigment mentioned in the bills of materials. I don't see how the white spots can be a result of changes in the aniline dye or the varnish.

I am beginning to think that the olive dye has shifted hue more by itself than through browning of the varnish medium. The latter has certainly yellowed enough to turn the underside blue turquoise (though not nearly as strongly as some artists have rendered it) and to mask any colour in the dark grey paint, but not enough to turn a colour almost universally called green in 1918 into a borderline green-brown.

Fokker would certainly have gone for the best value for his money, and a dye that changed from one camouflage colour to another would have been no burden, especially over the short expected life of a front-line aircraft. I suspect that UV light caused the hue shift, as the only contemporary British report of a brown paint on a Dr.I, AFAIK, refers to a long-exposed wreck.

Given the IWM's rigorous security in the present climate, I very much doubt whether any sample would be made available for analysis. That, sadly, is not the British way with exhibits. They do, however, seem to be "conserving" the samples in such a way that they analyse themselves!

[Dan_San_Abbott]

Gentlemen:
In the Fokker wing drawings, the zinc oxide is listed with the insignia black and only on the upper wing wing drawing. It is not listed on the middle or lower wing drawings. The insignia black is also listed on the lower wing drawing.
The insignia black and zinc white were not mixed to produce a grey for any wing whatsoever, they were use to paint the white crossfields and the black crosses only.
What Herr Timm said, the triplane was painted in "earth color". The Methuen Handbook of Colour defines "earth color as 5F2, "The colour of half dry earth or mould of the kind used in gardens." Methuen Code 5F2 is very dark olive brown.
Paul Leaman codified the color of the IMW Fok.DR.I 144/17fabric from 3D8, olive yellow, in lightest areas, to dark as
4F5/6. These are very close to Herr Timm's description as "earth color". While I did not codify the Sample I saw in 1972 it complies well with Paul's examination and codification. The Fabric can only change if exposed to sunlight over a long period time. The sample s stored in the IMW are kept in dark storage. I don't believe the color shift is the result of exposure to sunlight and I don't believe it will change over time. My take is, Gentlemen, you are flogging a dead horse!
For the life of me I don't understand why you all cannot accept the facts from Paul Leaman. For those of you who have the ability to go to the Imperial War Museum, do it and see for yourself.
Blue skies,
Dan-San

[Taz]

Dave, Acer, Dan-San- You are (I am just an observer) narrowing this down pretty rapidly. Between the three of you, I think you have all the answers we need.

Dave, Rick- I am convinced (and it sounds like you are, too) 588/17 (583/17 for years in publication, since Wenzl's 178/17 was assumed to be 588/17 for some reason) was painted in standard Dr.I colors and had no blue overpaint. If blue was one of the three pigments Acer mentioned, it would be on all Dr.Is. I have heard no mention of that in any source and believe the 588/17 report is just being misread or was poorly written, and the blue referenced was on the bottom and the streaking referred to the returned blue paint.

Acer- If two of your pigments are olive green and gray, what is the third? If it is blue, that would answer a lot of questions. If so, though, that would imply the Fokker M series biplanes and the AEG C.IV were similarly painted by Fokker.

Dan-San- The actual quote from Timm was "erdgrau", which is earth gray, whatever that is. As I said, that color covers a lot of possibilities.

Dave- I agree that the blue overpaint of the F.Is is purely supposition and based on no facts. The similarity of contemporary Fokker M series and license built AEG color schemes blows that theory out of the water.

Incidentally (and completely off the subject), a photo of 178/17 shows the serial number (178) on the left side of the elevator, not the WN 1896, which is only on the right side of the elevator. Wonder if there is any other photographic evidence of this marking scheme?



Taz
Terry Phillips

[Dan_San_Abbott]

Acer:
Where are you getting the grey? There is none listed on the wing bill of materials? On the middle and lower wing, zinc oxide is is not listed on the bill of materials. On the middle wing bill of material there is no black listed. There is no grey listed on any of the wing bill of materials.
I would like to know where are you getting grey?
Blue skies,
Dan-San

[Welsh Dave]

If you can, Dan, go to the IWM and see for yourself the dark grey streaky fabric now also attributed to 144/17, and the white spots erupting out of the darker green/brown streaks. They will not disappear
just because you deny them from 6000 miles away! I heartily recommend anyone within range to go and confirm them.

I don't have the list for the middle wing before me, but here are the lists for the upper wing

750 gr. Terebine or Rapid. Quick-drying varnish or accelerating additive
800 gr. Überzuglack (Libelle) Top-coat varnish (Libelle brand)
700 gr. Blaue Lackfarbe Blue enamel paint
13.5 kg. Emaillit Emaillite cellulose acetate clear dope
1.5 kg. Verdünnung Thinners (composition unspecified)
10 gr. Anilinfarbenpulver Aniline dye powder
300 gr. weisse Decklackfarbe White finishing enamel paint (for insignia)
100 gr. Signierschwarz Insignia black
200 gr. Rostschutz Rustproofer
1 kg. Zinkoxyd Zinc oxide (white powder pigment)

and the lower wing.

500 gr. Terebine oder Rapid
7 1/8 kg. Emaillit
1,5 kg. Verdünnung
500 gr. blaue Lackfarbe
5 gr. Anilinfarbenpulver
300 gr. Weisse Lackfarbe
500 gr. Überzugslack (Libelle)
1 kg. Zinkoxyd
250 gr. Ultramarinblau
100 gr. Signierschwarz



As you can see, both have white enamel paint and insignia black, neither present in the middle wing list if I remember correctly. These are in about the right proportions for painting the national insignia with the full white field.

There is a whole kilogramme of zinc oxide for each wing, more than three times as much as the white paint that already accounts for the insignia!! What on Earth were they doing with that much of the stuff if they weren't using it to extend and lighten the blue varnish, just as Alan wrote, and to give a slight body to the streak paint? Note that the varnish is blue, not turquoise, a colour rarely found in the sky. Turquoise came with yellowing of the varnish.

Note the ultramarine blue in the lower wing list, compiled on a different date.
It's probably for tinting the second layer of dope, but why doesn't it appear in the upper wing list? These lists are snapshots of what was considered to be required at a given moment; like aircraft drawings in general, and as a museum worker I've seen hundreds, they probably evolved along with the airframe design and as the practicalities of production emerged. There may have been versions that did give colours for the dye powder. I cannot believe they were set in stone, with all their inconsistencies of content and quantities, for the entire Dr.I production run.