rlm65 a bit confused

[Nick Millman]

During our interview with Warnecke & Böhm years ago they pointed out RLM 65 did in fact change. Their latest formula was dated 23 April 1942 and is as follows; KL 102H (Ikarol resin), Talcum 1727, Titanium dioxide, Lithopone white gloss Grillo,. Blue 1152, Yellow 420 N, Hydrated Chromium Oxide Green U 700 and a tinting with paste B. So I asked them with this formula could they reproduce the paint. They explained there was no way as these chemicals contained lead and were outlawed. Some variation in paint is, especially late war, due to the use of Italian manufactured paint using RLM specs.

Cheers, Jerry

Some of those pigments are still in use today and not outlawed at all. 'Blue 1152' and 'Yellow 420 N' don't identify the actual pigments. Titanium Dioxide, Lithopone and Chromium Oxide are all still in use. Talcum is hydrous magnesium silicate used as a matting agent, filler/extender and to impart other qualities to the paint. Still in wide use - not outlawed. As paint manufacturers W&B would be able to source an alternative if the yellow was Lead Chromate (Pigment Yellow 34 aka Chrome Yellow) so their excuse rings a little hollow. This factor did not prevent Jurgen H kiroff of Farben Kiroff Technik from reproducing the paints from their original formulae.

Just for the record here is the actual quote from your book 'The Focke-Wulf Fw 190 Dora' Volume Two' (page 304):-

"RLM 65 Light Blue was based on Chromium Green oxide, a stable, earthy, cool pigment."

It doesn't mention the other pigments you have now listed here (thank you) but presumably your statement that the colour was based on GREEN means that the Chromium Green oxide (sic) was the predominant pigment in the formula?

Chrome Green (Pigment Green 15) contains Lead Chromate but shifts colour with age. It is not considered stable.. Chromium Oxide (Pigment Green 17) is Chromium(III) oxide - a dull yellowish green to mid green much used in green camouflage paints due to various qualities.

Viridian (Pigment Green 18) is hydrated chromium III oxide, can be described as a cool, blueish green and may be the 'Hydrated Chromium Oxide Green U 700' pigment that you are trying to describe. Not really "earthy" though.

The change in formula might have been intended to counter the effects of exposure and chalking by deliberately deepening the colour saturation of the paint to begin with.

Nick

[Nick Millman]

Now then Nick, what are your thoughts on age yellowing off celluloid films the RLM test cards were produced on. I understand some paints will yellow if kept in the dark; the yellowing being a separate process to sun bleaching.

Herr Kiroff comments about this in 'Colour Charts' on page 2 of his German Paint Technology Appendix in Vol. 2 of the Merrick book. I can't really add much to that!

The yellowing is similar to the yellowing of varnish in old decals which can be corrected by 'sun bleaching'. Storage temperature is also a factor. The pigments can be affected by photo-chemical activity and other factors but that is pigment specific and can be both holistic and cumulative, impossible to summarise in terms of a predictive standard applicable to all paints and colours. Photo-chemical activity can cause colour shifts in paints composed of mixed pigments. Some pigments, counter-intutively, will gradually darken with UV exposure.

The artifact shown by Touvdal shows little obvious evidence of yellowing but it appears to be fabric and might therefore have been doped with a pigmented cellulose acetate butyrate. Characteristics of that dope are that it is clear rather than amber in tone and does not readily yellow with age. That being the case it is probably a useful example of the RLM 65 colour. I can't detect any turquoise or greenish undertone from those images but the W&B formula described by Jerry Crandall does suggest a turquoise element in that paint, depending on proportion of pigments. Hopefully he will share that with you.

The puzzle of RLM 65 hue goes back a long way. I remember following Ray Rimmel's mix for the 109 in his 1980s Scale Models magazine Battle of Britain series and being surprised at how deep a blue it was!

Nick

[Nick Millman]

Yes, there are different shades of RLM 65. Prior to late 1941, more of blue hue. After that, more of a green hue. Though two colors, it remained RLM 65.

Mark Proulx

Please provide actual colour values for those "more blue" and "more green" hues, thanks.

Nick

[Fernando]

Hi, gentlemen,

Without arguing in any sense the very knowledgeable statements made above in this thread, "thinking strictly in modelling terms and IMHO", I would say that a "rather strong sky Blue" is akin to RLM65 and that a "pale grayish light blue" is akin to RLM76 (making necessary allowance for the "even more pale grayish light blue" also known by some as Weissblau, typical of very late war night fighters). IMHO, in modelling terms, that is the difference to save, so to speak.

The picture in the beginning of the thread is a bit extreme, but we know digital colour pictures in computer screens are not to be trusted. I have used Xtracolour/Xtracrylixs RLM65 and found them a bit stronger in chroma than, say, Humbro 65 (has someone a funded knowledge opinion on the number of that paint? sheer coincidence or intentionality?), which, to my eyes, has a bit of green in it.

Regards,

Fernando

[PhantomBigStu]

Hi, gentlemen,

Without arguing in any sense the very knowledgeable statements made above in this thread, "thinking strictly in modelling terms and IMHO", I would say that a "rather strong sky Blue" is akin to RLM65 and that a "pale grayish light blue" is akin to RLM76 (making necessary allowance for the "even more pale grayish light blue" also known by some as Weissblau, typical of very late war night fighters). IMHO, in modelling terms, that is the difference to save, so to speak.

The picture in the beginning of the thread is a bit extreme, but we know digital colour pictures in computer screens are not to be trusted. I have used Xtracolour/Xtracrylixs RLM65 and found them a bit stronger in chroma than, say, Humbro 65 (has someone a funded knowledge opinion on the number of that paint? sheer coincidence or intentionality?), which, to my eyes, has a bit of green in it.

Regards,

Fernando

I have used xtracrylix and my 109 looks like the one I posted to the mk1 eyeball

same conditions this one in hum65

[Garry c]

A few questions about the aileron:

What colour are the ribs?

Is that red primer under the RLM 70?

The inside fabric looks pink, age or red dope bleeding thru?

Off topic I know

Just curious,

Garry c

[Jamie @ Sovereign Hobbies]

I saw a note in Kiroff's booklet that 7109.65 was supposed to be applied over red primer, so that would probably stack up for a Bf110B.

[Jerry Crandall]

Does anyone know the source of the formulas that Jurgen used for his chart? They weren't from W&B. What original formulas? I remember him telling us he got the colors from Eddie Creek. However I could be wrong. Some of the colors do not match up with existing samples that we have in our collection. W&B's patented resin base strongly resisted fading and it was relatively flexible and its big selling point was it adhered to aluminum and magnesium eliminating the need for any primer. There are recovered a/c parts from different areas and units that match amazingly well. Those same properties apply to artist colors acrylic versus oil. Acrylic is a tough, fade resistant paint. The RLM 45 red oxide anti-fungal primer used on fabric under camouflage paint was used. Of course, some pigments are still in use, I use some of these in my paintings almost daily, Chromium Oxide Green etc, but the dangerous qualities that early paint had, have been mostly eliminated. When the foremost Luftwaffe paint company that says they cannot produce RLM colors based on THEIR own formulas, I have to go with their word. Anyone is welcome to come to our facility here in Montana, USA and see what we have in our collection and materials and discuss colors.

Cheers, Jerry

[Nick Millman]

Does anyone know the source of the formulas that Jurgen used for his chart?

Cheers, Jerry

Why not ask him?

http://www.farben-kiroff.de/kontakt-2.html

Although he covers it in some detail in his Appendix on German Paint Technology 1940-1945 contained in Volume 2 of the Merrick book on Luftwaffe colours.

Nick

[Nick Millman]

I saw a note in Kiroff's booklet that 7109.65 was supposed to be applied over red primer, so that would probably stack up for a Bf110B.

Gustav Roth's formula for "brown" primer for light metal land aeroplanes consisted of zinc white, zinc chromate and carbon black with talc in W&B's artificial resin No. 600 binder and Xylol and Toluol solvents. The W&B artificial resins were reported to be oil modified phenol-alkyds and were supplied to other paint manufacturers in Germany.

The fabric coating process used dopes of different composition to the metal primer and incorporating the red oxide pigment in the first tautening coat.

Nick

[Jerry Crandall]

Jurgen and I toyed with the idea of him producing acrylic model paint and we would distribute it world wide. It turned to more hassle for us than it was worth. Then we tried to sell the idea of him producing paint for full size aircraft builders and restorers here in the US. The reception to that idea was not very encouraging mainly because of shipping paint across the pond. The old Monogram paint RLM 65 chip is accurate also. Mike, I'll have the information on the Italian colors out soon.

Cheers, Jerry

[Nick Millman]

Here are the RLM 65 colours from Monogram, the Kiroff Farbtontafel and Tafel 5 (1941) rendered in sRGB from L*a*b* measurements of those chips. The green in the Monogram chip is apparent.

The Munsell values are as follows:-

Monogram = 3.2 BG (Blue Green) 6.1/1.3 with closest FS 595 being 26329 @ 1.15 where < 2.0 = a close match

Kiroff = 7.3 B (Blue) 6.7/3.2 with closest FS 595 being 35450 @ 3.57 (the FS is brighter and less greyish)

Tafel 5 = 7.4 B (Blue) 6.6/3.2 with closest FS 595 being 35450 @ 3.55 (ditto)

Nick

[JosephLalor]

The puzzle of RLM 65 hue goes back a long way. I remember following Ray Rimmel's mix for the 109 in his 1980s Scale Models magazine Battle of Britain series and being surprised at how deep a blue it was!

Nick

He lightened Humbrol Authentic Prussian Dragoon Blue if I recall correctly

[Jerry Crandall]

The Kiroff chip is slightly too blue when matching our samples and chips.Of course looking at a computer screen is not 100%.

Jerry

[Mark Proulx]

FWIW, Ullmans opus Luftwaffe Colors 1935-1945 provides color chips. Among the choices is RLM 65 Hellblau (1938) which is more towards blue. Another chip, presented immediately beside is RLM 65 Hellblau (1941) which is more towards green.

Note same RLM designator and name but in two different colors for different periods in time.

Mark Proulx

[MIkeMaben]

Mike, I'll have the information on the Italian colors out soon.

Cheers, Jerry

Thanks Jerry, I ask because paints manufactured elsewhere would

definitely account for color variation.

Probably not easy info to track down.

[Fernando]

Hi, PhantomBigStu,

Yep, that's exactly what I meant. Humbrol has a distinct though slight greenish tinge, Xtracolour is more of a pure Sky Blue. YOur pictures show that clearly.

Fernando