The decal softening solutions work in different ways depending upon which one you have
They don't make the decal stick any better as such but improve the chance by eliminating air bubbles underneath the decal. They also soften the decal to allow it to better confirm to the detail underneath them. Some decals are impervious to certain decal setting solutions and require different techniques to assist in application.
The first step in successful decal application is to have a smooth glossy surface. This is achieved by applying a gloss varnish, gloss paint or Future floor polish (actually its a gloss acrylic varnish) My personal preference is to use a gloss clear coat that was designed for specialised metal finish paints
Use warm to hot water to soak your decals (this is an aid to making them more flexible)
Do not let your decal lift off the paper whilst still in the water (this will wash the glue away)
Depending upon which decal solution process you are using apply the "wetting" solution (the vinegar smelling one) This breaks surface tension
Apply your decal into the wetting solution.
AVOID moving the decal as much as possible.
Allow to dry a little while
Apply setting solution (this is the one that softens the decals)
If the decal starts wrinkling at this stage DO NOT TOUCH it (wait until dry it should (crossing fingers) smooth out) If it does not well then you have some work ahead of yourself.
Repeat if necessary.
Any silvering (air between the decal and paint) can be addressed by pricking the spot with a pin (or sharp scalpel slice) and applying more setting solution
Repeat as necessary.
When decals are dry (at least 24 hours) wash the model to remove any residue
Allow to dry again
Apply final varnish finish to seal decals and get desired final gloss/matt finish.
Of course metal finishes are slightly more difficult as the varnishes (especially the enamel/lacquer based ones) discolour the metal finish. Work with acrylic varnishes for better results here
Some decals are known to be very difficult and require more specialised techniques.
One is to use a plain tissue (no embossing on it) soaked in hot (as hot as you can stand) water and then applied to the decal under pressure (be careful you can crack joints on your model if you apply too much pressure)
I have used lacquer thinners applied with a almost dry brush on very stubborn decals. be very careful when doing this you can damage your paint finish if you apply too much. Apply the thinners ONLY on the decal and do not make it wet. Less is better here, rather repeat than screw it up with too much
There are a number of different decal setting solutions around as well. Some are too "hot" for certain decals and will melt them, others dissolve the ink (Tamiya decals are/were prone to this)
Test on a scrap decal before committing to your model if this is the first time you are trying this
The Humbrol decal fix is a pretty generic and reasonably safe version of the setting solutions. IIRC Humbrol did do a two part version but have not seen it here for some time. As to varnishing, on aircraft it is normnally best to varnish the entire aircraft before decalling. Most varnishes are not absolutely clear and do change the base colours slightly. This is especially true of enamel/lacquer/poly urathane varnishes.
Armour modellers can get away with just doing the spot where the tactical markings go as they tend to weather more heavily afterwards so can hide the colour change better.
Decal setting solutions
the decal softening solutions work in different ways depending upon which one you have
They don't make the decal stick any better as such but improve the chance by eliminating air bubbles underneath the decal. They also soften the decal to allow it to better confirm to the detail underneath them. Some decals are impervious to certain decal setting solutions and require different techniques to assist in application.
The first step in successful decal application is to have a smooth glossy surface. This is achieved by applying a gloss varnish, gloss paint or Future floor polish (actually its a gloss acrylic varnish) My personal preference is to use a gloss clear coat that was designed for specialised metal finish paints
Use warm to hot water to soak your decals (this is an aid to making them more flexible)
Do not let your decal lift off the paper whilst still in the water (this will wash the glue away)
Depending upon which decal solution process you are using apply the "wetting" solution (the vinegar smelling one) This breaks surface tension
Apply your decal into the wetting solution.
AVOID moving the decal as much as possible.
Allow to dry a little while
Apply setting solution (this is the one that softens the decals)
If the decal starts wrinkling at this stage DO NOT TOUCH it (wait until dry it should (crossing fingers) smooth out) If it does not well then you have some work ahead of yourself.
Repeat if necessary.
Any silvering (air between the decal and paint) can be addressed by pricking the spot with a pin (or sharp scalpel slice) and applying more setting solution
Repeat as necessary.
When decals are dry (at least 24 hours) wash the model to remove any residue
Allow to dry again
Apply final varnish finish to seal decals and get desired final gloss/matt finish.
Of course metal finishes are slightly more difficult as the varnishes (especially the enamel/lacquer based ones) discolour the metal finish. Work with acrylic varnishes for better results here
Some decals are known to be very difficult and require more specialised techniques.
One is to use a plain tissue (no embossing on it) soaked in hot (as hot as you can stand) water and then applied to the decal under pressure (be careful you can crack joints on your model if you apply too much pressure)
I have used lacquer thinners applied with a almost dry brush on very stubborn decals. be very careful when doing this you can damage your paint finish if you apply too much. Apply the thinners ONLY on the decal and do not make it wet. Less is better here, rather repeat than screw it up with too much
There are a number of different decal setting solutions around as well. Some are too "hot" for certain decals and will melt them, others dissolve the ink (Tamiya decals are/were prone to this)
Test on a scrap decal before committing to your model if this is the first time you are trying this.
Decal Setting Solutions
NOTE: Decal Setting solutions can have an adverse effect on your decal. Some are very "hot" (strong) and will melt a decal. test with a spare decal before using on your latest masterpeice. Some decal setting solutions work better with certain decals than others.
Solvaset
This is a single part (unlike most others) system and is very hot, I have melted Microscale decals with this system but is very useful for stubborn decals.
Microscale system (The Superscale system is the same)
The original
Mr Mark Softener
Part of the Gunze range of model finishing products. A two part system that works with most decals.
Tamiya
Tamiya joined the decal finishing process late. I believe that this system works well with Hasegawa decals. Thye also produce it in two strengths which is useful
Humbrol
The Humbrol decal fix is a pretty generic and reasonably safe version of the setting solutions. IIRC Humbrol did do a two part version but have not seen it here for some time.
Heat
Some modellers are using a low powered haior dryer to help decals settle down. I myslef have not tried this method as yet, Be careful with heat though, you might warp your kit.
Sealing it all in
As to varnishing, on aircraft it is normally best to varnish the entire aircraft before decalling. Most varnishes are not absolutely clear and do change the base colours slightly. This is especially true of enamel/lacquer/poly urathane varnishes.
Armour modellers can get away with just doing the spot where the tactical markings go as they tend to weather more heavily afterwards so can hide the colour change better.
Preserving/Saving decals
Occasionally decals will show evidncne of crumbling, Tamiya and HAsegawa decals are chief culprits here. Once cracked there is very little one can do but replace. Some decals (especially ALPS printed, or similar) require an overcoat as there is no varnish to bind the colours. The Microscale system had a Decalfilm that helped, or even a good quality varnish applied ove rthe decal and left to dry before using the dcal, You will need to trim close to your subject before using
Reaction to decal softening solutions
I have heard that MAV decals (a South African cottage industry) are more difficult than most and will (or may) need more persuasion. The hot water and tissue with pressure trick is very good to bear in mind. Another trick is to use a small pool of future where the decal is going to sit, make sure that the decal is not swimming in water/solution and apply onto of the future. As it dries it shrinks a bit. Once again practice this before committing to your final decals.
ESCI decals seem to be impervious to any known setting solution. Heat treatment here does work.
