Late-war Fw 190 painting observations

[MDriskill]

In this recent thread on another forum, I learned about "Lionoil": a WW2-era tinted varnish coating. It was used on aluminum sheets prior to final fabrication, to seal the surface, provide scuff protection, and help highlight scribed work markings. It was typically (though not always) removed before permanent corrosion protection or finish paint was applied. A similar process is common in aircraft construction to this day.

 

https://www.tapatalk.com/groups/hyperscale/ww2-aircraft-sheet-metal-question-t527181.html

 

These images, from Osprey's Production Line to Frontline, Focke Wulf Fw 190, suggest that German wartime construction did something very similar:

 

 

 

This might be of interest in the ongoing debate re: late-war German fighter painting. If the well-known autumn 1944 directions to simplify aircraft finishes affected applying - or perhaps more importantly, THE NEED TO REMOVE - this type of coating, that might have some visual repercussions. 

 

Example 1: This photo may show the coating remaining on the inboard underside wing panels. They look much different from the adjacent bare metal on the outer wing, fuselage underside, and access hatches. And note how some of the rivet heads are highly visible as lighter spots - not unlike the shot above of a lower wing in the assembly jig:

 

Example 2: Coating remaining on the rear fuselage, could explain the odd dark appearance of these un-camouflaged underside panels...

 

 

...or this dark "mini swoosh" on the side:

 

It would be interesting to know what color(s) the German coating material was. I'm guessing some shade of gray (or at least not bright blue like the Curtiss version). 

Edited December 21, 2021 by MDriskill

[dov]

Hallo

 

Whatever the exact components of Lionoil are, it is an oil.

So, consequently you must remove it, before applying a coat of color.

No matter which one.

It is the same effect as on your model, the color would separate from the surface.

I have no idea in which form: Stripping, or flaking or reacting with the coat above.

Lionoil on the sheet makes a fabrication process possible.

Bending, cupping, deep-drawing etc.

The photos you show, example 1 here we have according literature unpainted sheets.

Here I assume the Lionoil would not be removed.

Example 2 is a guess only.

No fact really.

Shades from light also exists.

It is an interpretation beyond facts.

Example 3 the same, guess only.

 

Happy modelling

[MDriskill]

Thanks Dov. One correction to start please - in spite of the company name, the "Lionoil" Prussian blue shop coating is not any sort of lubricating oil. It was a varnish - a durable coating that dried hard and took a solvent to remove. And it was possible to apply paint over it, though that was not often done on exterior surfaces of US aircraft.

 

The HyperScale thread that I linked above describes details of the material and how it was used. Here is a another great article, with many color photos  (originally published during the war in "Life" magazine) - you can see Lionoil stayed in place on P-40's until they were ready for final finishing.

 

https://inchhighguy.wordpress.com/2021/09/22/curtiss-wright-p-40-warhawk-production-color-photographs-part-i/

 

I'm only speculating that in the late-war days of simplified German aircraft painting, they might not have always taken time to remove similar shop coatings, at those exterior areas not requiring finish camouflage painting.

Edited December 7, 2021 by MDriskill

[Werdna]

2 hours ago, MDriskill said:

I'm only speculating that in the late-war days of simplified German aircraft painting, they might not have taken time to remove a similar shop coating, at exterior areas not requiring camouflage.

 

In the spirit of 'speculation', I've been reading recently about the 'swoosh' on other forums (and mentioned above).  Is it possible that it's not actually a 'painted-on' feature, but rather what remains after the fuselage camo has been painted over the aforementioned lionoil-type coating?  (am I making sense?).  Some late war camo pattern drawings (there's a couple on one of the old Ta152 threads) seem to suggest that kind of demarcation with the underside in a bare metal finish.

[MDriskill]

I was the miscreant who also started the HyperScale "swoosh" thread... 😜

https://www.tapatalk.com/groups/hyperscale/more-late-war-fw-190-fun-the-swoosh-t527476.html

 

There we kicked around two ideas: that the swoosh was either deliberately added, or was "left over" from a reduced application of paint on the fuselage sides. We found some that were incontrovertibly the former (paint visibly overlapping the fuselage cross, etc.)...but I still wonder if others were the latter.

 

And here is something I recently stumbled into, to reinforce that idea - a November 1944 painting diagram for the Ta 152:

 

Note the demarcation line on the rear fuselage. Assuming contemporary "official" patterns for the 190A and D were similar, swooshes may not be accidents or sloppy work, but actually the byproduct of a "textbook" factory finish.

Edited December 8, 2021 by MDriskill

[Werdna]

That's it - that's the drawing I had in mind.  If that's the case, then it does seem possible that it was indeed some kind of unpainted, 'darkened' metal finish....perhaps....

[GiampieroSilvestri]

The colour description of the drawing says the fuselage had to be painted in RLM 76 with the upper part in RLM 81 Braunviolett.The complete fuselage under the waved line does not show the symbols for the camouflage colours so it is probable that the fuselage sides were left unpainted partially.

 

Saluti

 

Giampiero

Edited December 6, 2021 by GiampieroSilvestri

[SafetyDad]

Very interesting and a great spot there.

I've skimmed the HS thread (while dodging the adverts - grrr) so I think I've absorbed the differing viewpoints.

I was tempted by the 'propwash throwing up mud' idea, especially on 'White 61', but, while plausible in my view, it's hard to promote this as a single explanation given the consistency and apparent uniformity of the 'swoosh' on all the pictures posted. I decided to widen the views for this 'mud' hypothesis, and looked at Bf109 pics to see if the 'swoosh' could be seen there - if it's mud then perhaps it would be seen? Although the propwash pattern would be different. No Bf 109 swooshes so far.

 

I do think that your Lionel coating hypothesis has merit though, both here in the case of the fuselage 'swoosh' and perhaps even more so in your suggestion of underwing tonal variations.

 

SD

[tank152]

Personally I think you're just seeing what you want to see.

A bit like the NMF finished Fw190's people are obsessed with, which is a perfect example.

 

All more than likely due to tricks of light.

 

 

[tempestfan]

12 hours ago, GiampieroSilvestri said:

The colour description of the drawing says the fuselage had to be painted in RLM 76 with the upper part in RLM 81 Braunviolett. The complete fuselage under the waved line does not show the symbols for the camouflage colours so it is probable that the fuselage sides were left unpainted partially.

 

Saluti

 

Giampiero

No, it doesn't say Braunviolett, it says "Farbton 81" 😉 BTW, there are also some 82 areas prescribed on the fuselage.

As the sections near the tail would probably count as Flugzeugunterseite, it would seem plausible that "bleibt ohne Sichtschutzanstrich" extends to them. 

[SafetyDad]

2 hours ago, tank152 said:

Personally I think you're just seeing what you want to see.

A bit like the NMF finished Fw190's people are obsessed with, which is a perfect example.

 

All more than likely due to tricks of light.

 

 

 

Are you referring to the Lionel coating suggestion or the 'swoosh' pattern on the rear fuselages here?

 

SD

[tank152]

2 hours ago, SafetyDad said:

 

Are you referring to the Lionel coating suggestion or the 'swoosh' pattern on the rear fuselages 

The Lionoil coating is just guess work. The patterns etc mist likely tricks of light etc. I'll refrain from using the swoosh as before long it'll be used as if it's an official term. We all know how these things get out of hand as time goes on on-line

All of this reminds me of the nonsense of German Armour being sent out in red primer towards the end of the war.

This is fine if taken in the context of "What If"  and for a bit of fun.

[Werdna]

The 'swoosh' proposal/theory (the name isn't ideal, but then neither are names like RLM84, but it's still clear what is being referred to) does seem to fit in terms of unpainted panels and late war camo patterns, as demonstrated above.  There are enough pictures out there (mostly b&w admittedly) which seem to show this feature, all taken from various different angles, which would seem to rule out the 'trick of the light' defence.

 

So at the moment, we see a number of pics of (mostly, I think) Fw190s, all apparently with the same or similar tonal/colour variation at roughly the same section of the fuselage, while we also have evidence of a RLM camo pattern diagram, which - if followed correctly - might actually produce an effect similar to that seen in the pics - especially if the panels in question had received some kind of protective/anti-corrosive treatment.  I'd say that's at least worth looking at further.

 

The other alternative is that we all just accept the notion that knowledge of luftwaffe colours and paint application has already peaked and there is nothing more out there to discuss.  Stuff like this is often hiding in plain sight - discussion is harmless and it might even lead to something, or it might not, who knows.

[Wulfman]

My theory is that the so called RLM 84 is varnish 99 painted over poor quality RLM 76 to preserve it, albeit completely unfounded !

 

Wulfman

[MDriskill]

Withdrawn 

Edited December 20, 2021 by MDriskill

[Werdna]

I was expecting a pic of Lionel Messi then, tbh.  That just demonstrates my preconceived ideas about 'Lionels', unfortunately...  

[MDriskill]

Well OK then. Now that the most important point has been established (that I am too stupid to know a "trick of the light," LOL); back to the other question at hand - does anyone know details of how Lionoil-like sheet metal shop coatings were (or were not) used for aircraft manufacturing during the war, outside of the US?

 

Technical details like this can be very interesting, and relevant to modeling in unanticipated ways.

Edited December 20, 2021 by MDriskill

[SafetyDad]

1 hour ago, Werdna said:

The other alternative is that we all just accept the notion that knowledge of luftwaffe colours and paint application has already peaked and there is nothing more out there to discuss.  Stuff like this is often hiding in plain sight - discussion is harmless and it might even lead to something, or it might not, who knows.

 

That's so true.

 

A great example is Dave Brown's epublication exploring the camouflage and markings of Fw 190A-6 'Brown 6' of II/JG26. We've all seen the pictures of it stood on its nose and you would now think it rather unremarkable. But Brown dissects the available evidence, and very convincingly proposes the use of RLM77 as one of the upper surface colours using the photographs that we've all seen before.

 

Discussion is not just harmless - it's essential if we seek to better understand any subject. If any given idea is contentious, then reasoned, thoughtful debate using evidence can test it.  Ideas are adjusted and amended accordingly. Occasionally they are discarded.

If I recall correctly it was this analytical process that led Thomas Jentz to move away from his previously-held view that late-war German armour appeared partially or completely painted solely in primer? 

 

 

SD

 

[tank152]

The difference is people such as David Brown have use of the actual print and not something that has been shared countless times over the Internet each time of which would have altered the tones etc. 

Discussion such as this is fun and nothing else i'm afraid. 

 

As someone who has worked in the steel industry all my life I can assure you that by varying the angle of what you take the photo the same piece of steel can be made to look polar opposites. Also the grain in a sheet of steel would also make the sheen look completely different if it was at 90° to another sheet. So you could have 2 panels cut from the same sheet and look completely different to each other when photographed. That is my take when you see photos of wing under surfaces.

[dov]

Here I have to add a side step:

 

Aluminum is according to latest medical research reports from ministry of health in Austria responsible for breast cancer and Alzheimer diseases.

I found it right now, accidently, because I look for old reports of manufacturing processes with duralumin.  

 

https://www.sozialministerium.at/dam/jcr:98ac593d-80e4-46b5-b8fd-5943427d32ac/aluminium_studie_2014.pdf

 

Equivalent reports may exist in other countries too.

This one is in German.

 

The aluminum was transferred from the aero industry toward the civil market after the war.

Consequently all utilities were produced with this material.

Another wonder material post war was plastic.

Aluminum was used widely.

At this time started with dishes, bottles etc. and today with foil.

In each case takes this report a spot on and checks it.

The drinking from aluminum bottles or cans, as it is used in automates today, yes they carry this poison in it.

 

Happy modelling

 

[Graham Boak]

Before anyone rushes to replace their pans, this is an old scare which has yet to be accepted (except apparently in Austria).

[MDriskill]

I appreciate everyone's comments on this. The points regarding variations in old photos and internet reproductions are certainly true, and well-taken.

 

But the spectacularly clear underside photo of "Yellow 14" is vastly better than the average wartime shapshot. Its many crisp details include the demarcation lines on both wings (whose dihedral helpfully puts them at different angles to the light) between the dark finish on the big inner panels - whatever it may be - and the adjacent bare metal (the most telling spot may be the short panel line at the outer gun bay: same material, same angle, two different colors).

 

 

To illustrate the point - another shot of the same machine. The differing angles of the airframe and light add useful counterpoints, but the lesser technical quality of the image of course lessens our ability to describe details (yet the darker inner wing panels are still evident).

 

 

(Career notes now apparently being relevant...I practiced architecture for 45 years, 25+ of them managing sizable projects. Color questions; "tricks of the light;" interpreting drawings, regulations, and photos; and understanding real-life appearance of many different materials; were my literal stock-in-trade.)

Edited December 9, 2021 by MDriskill

[GiampieroSilvestri]

18 hours ago, dov said:

Here I have to add a side step:

 

Aluminum is according to latest medical research reports from ministry of health in Austria responsible for breast cancer and Alzheimer diseases.

I found it right now, accidently, because I look for old reports of manufacturing processes with duralumin.  

 

https://www.sozialministerium.at/dam/jcr:98ac593d-80e4-46b5-b8fd-5943427d32ac/aluminium_studie_2014.pdf

 

Equivalent reports may exist in other countries too.

This one is in German.

 

The aluminum was transferred from the aero industry toward the civil market after the war.

Consequently all utilities were produced with this material.

Another wonder material post war was plastic.

Aluminum was used widely.

At this time started with dishes, bottles etc. and today with foil.

In each case takes this report a spot on and checks it.

The drinking from aluminum bottles or cans, as it is used in automates today, yes they carry this poison in it.

 

Happy modelling

 

Another proof that "scientists" contradict themselves.Around two months ago I saw a report on a German TV channel that new research brought out that aluminium is not cancerogen.Ask four scientists and you get five different opinions.

 

Saluti

 

Giampiero

[Rolls-Royce]

20 hours ago, Graham Boak said:

Before anyone rushes to replace their pans, this is an old scare which has yet to be accepted (except apparently in Austria).

And aluminum cans are coated inside with polymer to seal the aluminum away from contact with the material being contained...

[dov]

Hallo GiampieroSilvestri

 

The thing is, to understand and interprete things correctly.

Here I can tell you, that news agancies are realy stupid.

By all means.

This people have no education in science, engineering or anything else, and explain you the world.

This is the matter.

Good journalist are starving.

In the matter of aluminum: The cancer probes of the breast have more as double concentration of aluminum.

All over the world!

The brain of Alzheimer autopsy also double concentration of aluminum or higher.

All over the world!

Maybe aluminum does not initialize it, but without aluminum it would be no problem at all!

This are facts! Really!

 

Make your own conclusio...

 

Happy modelling