Varnish Before Decals

[EC182]

Hello All,

I've almost finished painting my latest build and my thoughts are turning to decals and varnish.

 

For my last build I tried weathering for the first time, and it didn't work the way I'd hoped; by the time the varnish went on, much of the panel lining and other detailing had too much cover (between layers of paint and varnish) to allow the washes to run into them properly, or at all in some places.

 

This time, I'm trying to take a bit of a minimalist approach where possible, and have used just a single coat of enamel paint in an effort to avoid this problem with the washes.

Having done some looking around, the general consensus seems to be that you need a layer of gloss varnish underneath your decals, and another layer over them.

 

I'm wondering whether that first layer of gloss is really necessary for the decals to come out all right - I'll be using Decal Fix. If I try to apply them directly to the painted surface, and just gloss over that, is it likely to go wrong?

 

Thoughts appreciated.

[Peter s]

I'm an acrylic person but the principle is the same...... I tend to wave a can of Vallejo spray varnish over the model periodically as I go along. Thin coats but it toughens things up, protects weathering that may be water soluble (I use watercolour pencils a lot and the water from decals washes that off... ditto water based washes). The idea behind a varnish coat before decals is that the smoother the surface the less chance of decal frosting (water behind the decal spoiling the finish) but micro-sol and set help avoid that. A coat of varnish after decals protects them (its not the first time a roundel has come off on my finger the day after I applied it) and can help soften and conform the decal. New Tool panel lines are quite deep so you shouldn't fill them with a coat of varnish.

BTW a glossy finish sometimes repels washes and a matt finish can sometimes retain so much wash its hard to actually wash it. Depends on the solvent used in the wash and what effect you want. Organic solvent (ie artists turps, enamel thinner etc) tend to work better than water based ones.

 

Ideally you weather after applying decals as the effect would cover the whole area and often streaks look more obvious over a roundel than over a cammo wing. Flipside is that if you're not comfortable weathering you could overdo it and then lose your decals. Best to weather lightly then build up. The planes leave the factory spotless and generally the crew try and keep them clean. There's nothing wrong with a clean plane but you can over-weather and get to an unrealistic level. I'm always happiest with some pics of the real thing to keep me in check (although I found some Lancasters with so much exhaust filth you wouldn't believe it. Looked like the crew had been having a BBQ on the wing!)

[peebeep]

Humbrol claim that decals can be applied over a matt surface using Decalfix, video

.

 

In my own experience I would point out a couple of caveats.

 

• Soaking decals in undiluted Decalfix can cause them to fragment, unless you're completely confident they're robust
• Undiluted Decalfix can affect paint finishes because it is quite caustic

 

In recent times there has been concerted efforts from some parts of the modelling community to rubbish the technique of applying decals to a glossy surface and say that glossing is unnecessary. My own view is that physics of it are quite clear, decals adhere better with less chance of silvering onto a glossy surface than they do with matt. A glossy surface has always been the bedrock of the Microscale decal system.

[EC182]

Thanks for the replies - I think they have nudged me towards putting down that base coat of gloss before the decals.

 

The point about indiluted Decalfix is an interesting one, it didn't occur to me that it might eat the paint underneath if there wasn't a barrier of varnish there.

 

I have used pure Decalfix before and didn't have any problems with the decals coming apart, but I suppose that's something to be aware of too.

 

 

As for the weathering - come to think of it, many of the panel lines are raised, so obscuring them probably isn't going to be as much of an issue as with the previous build.

 

The build is an Italeri Mirage V in Belgian colours - most of them look pretty clean in the photos available online, so I won't be going to town on the weathering in any case.

[Ratch]

DecalFix is hot and aggressive. I've had it wash Tamiya paints out, even after a coat of Klear - and I always gloss before applying transfers.

[Peter s]

The most dangerous product I've used is Humbrol acrylic spray varnish. That can attack paint and decals too. Whatever the solvent is its potent. Its rare I get silvering even on a matt finish (a defiant was a recent rare exception) but I have found its harder to position a decal on a matt finish. Once it touches wing it often sticks quite firm. Flipside is that it doesnt decide to migrate when you turn your back so it works both ways.

[Kenneth ONeill]

Well, back at the "should you varnish?" question.  

YES! The reason that gloss varnish reduces/prevents silvering is that it stops air getting trapped under the clear film carrier of the decals between that and the slightly rough matt paint.

[fishplanebeer]

 A compromise would be to use Satincote or similar satin varnish as it will help avoid any silvering.

 

I note in my old copy of the Verlinden Volume III, 'On Plastic Wings' (the best guide ever published IMHO) he recommends using a satin varnish prior to applying decals and then a matt or semi-gloss (satin) coat to fix the decals and prepare for applying washes and it seemed to work pretty well for him. Once the washes are done the preferred final varnish coat can then be applied.

 

Hope this helps.

 

Regards

Colin.

[fishplanebeer]

 Just checked and this guide by Francois Verlinden is still available on a very well known on-line book site.

I highly recommend it as it is so much clearer and easier to follow than many other guides I've bought by Osprey and others.

 

Regards

Colin.

[ironsides]

Usually I would use a very thin coat of gloss acryllic varnish on areas where decals are to go to avoid foxing, sometimes this may include entire wing surfaces (lozenge for WW1 aircraft) and use microsol/set for application as this has proved to be the best in my experience, I follow this with a thin matt varnish on the finished model more often as not Mattcote and gloss or satin selectively if this is more appropriate, I havn't painted many all metal finishes though but these would either be gloss or satin for the final varnish... I should point out that I paint using brushes and occasionally a rattle can for large areas but never use rattle can spray varnish as previously I got poor results... but whatever you do if you can when applying decals allways test a sample first as they may be ultra fragile or respond in odd ways to the decal solution 😉

[EC182]

Thanks for the replies and advice.

The decals went on no problem. I can't believe I wasted so much Decalfix last time around by using it to soak the decals before taking them off the sheet. Completely unnecessary - plain warm water actually works much better for this, for anyone who didn't know.

Decalfix only needs to be painted on beforehand to assist with placement, and afterwards to bed down.

 

Weathering has also been done, lightly on the top side and somewhat more on the undersides. Raised panel lines made it a bit more difficult than it otherwise would have been.

 

Hard to know how much is too much - it's actually difficult to find a good photo of the undersides of a Belgian Mirage V, the only one I managed to find looks pretty grimy but it's hard to see it very clearly due to the lighting.

 

Most photos of Mirage IIIs show pretty clean undersides.

 

I'll post a photo later on and see what youse think.

[EC182]

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[EC182]

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