HU56 'Corroguard' Fail

[Ghostbase]

Have been quietly working on the new 1/48 Kitty Hawk F-101A/C Voodoo, bit of a challenge to say the least but satisfying for all that, least until I decided to apply the main colour.

Despite the instruction in the kit which show a shiny NMF I decided to try to match the dull aluminium colour that most photos taken of Voodoos at RAF Bentwaters show back in the early 60's. I read somewhere that the aircraft were painted in 'Corroguard' and the nearest Humbrol equivalent is HU56 Aluminium so I set up the airbrush, stirred and shook the tinlet of paint, and thinned it to a ratio about 1:10 with Humbrol thinners. The intention was to spray the undersides plus the tail fin first, then the top surfaces as a second spray. Unfortunately all did not go well.

The tail fin shows that where the HU56 went on well it looks very good however there are speckled areas. The view of the main body/wing under surfaces shows worse:

And just to really add to things there seems to be a 'tide mark' along the fuselage!

Not sure what is causing this. Maybe I didn't mix the paint properly (the tinlet was several years old), maybe I am not cleaning my air brush properly, maybe I am being too ambitious and trying to cover too much surface area, perhaps in doing so I am 'drenching' the area with paint.

Not sure what to do now. I still have the top spray to do yet so I could apply a very light sandpaper then respray the affected areas. If that shows no improvement then it is Mr Muscle and start again I guess

Michael

[bentwaters81tfw]

Irrespective of the paint problems, Voodoos were NEVER painted with Coroguard. I know exactly where you read that, and that guy has some very strange ideas*, and not just about the Voodoos. They were only NMF apart from 2 that were painted grey like the B models, and that was just prior to them returning Stateside.

You can either seal off the old paint with Klear and start again, or strip it off. If you want a NMF finish that is is dulled with weathering, I would recommend Halfords Silver over a gloss black undercoat. It is virtually foolproof and looks the part.

The guys that made the models for the Bentwaters museum use exactly that, and the results are superb.

*as is often the case, written by someone with no personal knowledge of the subject.

Here is one in the late scheme with a grey spine. A few of these were so painted, but you need to check your serials and refences.

[AngstROM]

I think Bentwaters is right about that -Corogard (in the Voodoo era) was a deeply horrible metallic sludge (Aluminium powder in a clear 'carrier') that luckless sailors had to brush-apply to bits of Navy aircraft to protect them from the ravages of the briny sea. Note that the stuff of that name applied to modern airliners is variable in its initial colour, but quickly weathers to a sort of dull light grey.

If I understand correctly, the silver coat (lacquer?) applied to USAF birds from 1960-ish ('Project Lookalike') was also an anti-corrosion finish, and required occasional buffing-up to prevent dulling over time -hence the wide variation in appearance between different 'Not NMF' airframes of the period.

As to the more pressing Humbrol problem, I know metallics in rattlecans have a definite (and relatively short) lifespan before the metal particle content starts to deteriorate, resulting in a very similar effect to that in your pics. Maybe the same happens with enamels?

When not using 'real' metal finishes like Alclad II, I recommend acrylics like Tamiya or Gunze Mr Metal colour (the latter being a little tricky to airbrush, but very realistic for NMF). There was superb build on here a while ago (a P-47?), but I can't seem to find it again, of course! Anyhow, this kit had been BRUSH-PAINTED with Mr MC and looked GORGEOUS -such a finish would grace any appropriate F-101A!

Maybe someone has a link...?

Edited November 2, 2014 by AngstROM

[Ghostbase]

Thanks for the comments and advice, appreciated and have learned a bit more, including don't believe everything that I read on t'internet! In the end I decided to go for a fresh tinlet of Humbrol Metal Cote 'Matt Aluminium' and it has covered the top surfaces very well, however the finished result is much lighter and shinier than I wanted. The reason I did this is to get the Voodoo finished otherwise I know it will end up on the shelf of doom. Will definitely try the Halfords silver over gloss black undercoat next time I build an aircraft from this era, sounds exactly right for an F-105D Thunderchief for example. Acrylics might also be the way to go, enamels require so much in preparation and cleaning time and I seem to have very hit-and-miss results. Michael