Re: RLM 81/82 – More secrets unveiled
 

Thanks for that, I'll look into purchasing that book. But AFAIK, the RLM regulated the use of as pilot said, nitrocellulose lacquers (clear) with added pigments (colours) & thinners, not epoxy. The Zinc Chromate used on bare metal surfaces was almost clear, with a slight tint of green.

Cheers

Re: RLM 81/82 – More secrets unveiled
 

Salut!

The most used Luftwaffe paints were not epoxy nor nitrocellulose.

Flieglack 7012 and 7122 were both based on phenol resin ("Phenolharzverkochung in aromatischen Kohlenwasserstoffen") and Flieglack 7155 was based on polyvinylchloride ("Polyvinylchlorid und Antimon in aromatischen Kohlenwasserstoffen").

See documents: http://www.rlm-farben.de/en/products...-coatings.html
(Kiroff paints)

Phenol resin is inherently flame retatrdant. Antimony addition probably does the same for the polyvinylchloride.

Of course there was other paint systems used on Luftwaffe planes. Although I certainly do NOT remember any epoxy paints. It would have been poor choice anyway because it chalks easily outdoors. Compare some modernish sailplanes like SZD Jantar.


Cheers,
Kari

Re: RLM 81/82 – More secrets unveiled
 

Hello Kari,

Perhaps they used phenol resin to mix with the nitro lacquer to make it flame retardant, but certainly not as a paint by itself I would think.

Re: RLM 81/82 – More secrets unveiled
 

Kari Lumppio- IG Farben also produced paints and coats, do you have any additional info about it? Thanks for links above :)

Re: RLM 81/82 – More secrets unveiled
 

""""Flieglack 7012 and 7122 were both based on phenol resin ("Phenolharzverkochung in aromatischen Kohlenwasserstoffen") and Flieglack 7155 was based on polyvinylchloride ("Polyvinylchlorid und Antimon in aromatischen Kohlenwasserstoffen").""""

http://en.wikipedia.org/wiki/Epoxy - look at 2.4 Phenols

Chemestry is not my strong side, so might be misinformed or wrong ( I can take that, thats part of learning more ), I see PVC plastics there - but the "composite chemistry" of the paints was basically that Luftwaffe paints need hardener ?

SZD Jantar is rather old by todays standards ;-) and yes, Gelcoat (epoxy or polyester based) often chalks outside.

Re: RLM 81/82 – More secrets unveiled
 

Epoxy is always two part, I worked many years with this materials (composite construction as well painting (paints are two part also)). It would be nice to hear about early epoxy coat use

Re: RLM 81/82 – More secrets unveiled
 

Not as a rule, but indeed there were hardener activated paints. There is a brand name by "Hoechst" dated from 1928 called "Desmophen".

Later (in the 80s) there still was a type of paint called "DD-Lack" (Desmodur-Desmophen) used to for an undisclosed hardener activated paint.

BTW, there is a BIOS report #365, German Aircraft Paints. It deals with the types and technology of german aircraft paints. As i have understood it no epoxy was mentioned. Instead, Nitro-cellulose, phenolic resin, modified oils etc were used.

Re: RLM 81/82 – More secrets unveiled
 

Hello friends,

I have read the topic here a bit amused ... all reads in part, quite adventurous.

Downright philosophical ... and I've caught myself a few times when you smile ;)

I've learned that you can identify as correct colors of photos, only ... when combined with a standard color card, preferably with neutral lighting was added.

This is done for a long time in scientific photos ... for example, in space exploration, on the Moon, Mars or underwater.

Photos do not allow conclusions on the true color to ... if they have not been included along with the respective standard color chart.
Just so the colors can be exactly determined.

The color photos or color negatives of our WWII pilots are simply too old that you could not determine exact shades with them.
They are corrupt, at best as a rough approximation helps visual orientation.

If you try color photos, color correct without categorize these tools, I look at the window-dressing, an illusion.

Even color samples of 3-D material in the form of painted wings or fuselage sections say nothing about how a color 80 years ago really looked.
Because ... Colors dry out with time, eg permanently lose Petro-liquids and other chemical substances ... regardless of whether they were exposed to UV light or not.
The surface structure of a color change over time.

This then changes the color and tonal value of a color, the aging process, some quite significant.

Tschüss :)
Heli

Re: RLM 81/82 – More secrets unveiled
 

Maybe not exact.. but damn close I would think :)

Re: RLM 81/82 – More secrets unveiled
 

Heli... nobody take color image or preserved sample as direct match, this is just guide where to search more. Any serious determination could be made with spectral analyze or with preserved original production specification. Also, it is well known that from black and white image can not be determined correct real color (this is double sword used among enthusiast to discredit others work...).

At least, it is good for health to laugh :) Welcome on forum:)