finishing car bodies with decals

[cor]

Hi there. I was asked to show what I do for finishing paintwork with decals for a glossy finish on car bodies.

On a racing car body, with lots of decals, I want to have the decals look like they are painted on.

First up, prepare the plastic body. Remove all seam lines, sand it smooth, fill any gaps lines with Mr Surfacer 500, which is a thick grey paint - I use a toothpick or old brush to fill the gap. Once its dry, sand the body all over, covering any detail with masking tape so it isnt removed.

I start with these foam back sanding pads, as they conform to the curved surfaces of the body. Use a 1000 grit or so to remove the excess gap filler, and generall sand all over the body.




Once the gaps are filled, use a finer grade sanding pad, or these Tamiya sanding cloths or similar, to get down to about 2 or 3000 grit.






The plastic should look pretty smooth by now, however I like to get it smoother using either a tissue folded into a square pad, which gives extra shine to the plastic, or it can be polished with Tamiya polishing compound. The medium blue can be used and the plastic will really shine.





Be sure to wipe off all the compound using a damp cloth, and let the model dry before priming.

Next up, spray a thin coat of well-thinned primer. I use Mr Colour 1500 surfacer or primer, and usually grey unless a black or white undercoat is needed to adjust the final coats saturation. Any fine primer will due. Even if the body paint is the same colour as the plastic, I will still prime, as this shows any defects in the body which can be dealt with - filled, sanded, etc. use a thin coat so there is not much build up of orange peel, unevenness, or splattering on the prepared plastic.

Once the primer is on, and the body is ready for the base coat, resand / polish the primer with a fine sanding cloth, and if you want, use a polishing compound again. You can even rub the primer with a folded tissue again, this gives a pretty nice shine to primer. The idea is to keep is super smooth, so the final coat has a smooth base to sit on. The more glossy, the better the final finish will be. Make sure every imperfection has been removed in the paint, and the plastic.


Now spray on a thin base coat. Let dry. Another thin coat. Let dry. Repeat until the color of the body looks the way you want it. Dont overdo it with thick paint as this can clog detail, and can present issues like running. Lots of very thin coats is the key, and stopping when the colour looks right for your model. Keep it thin so detail isnt lost to paint build up.

I always use Mr Colour Lacquers, and these dry very quickly, especially thin coats, and also thin them with Mr Leveling thinner, a drying retarder to allow the paint to smooth out a bit before it dries.

Let the body dry completely for the paint you are using. This should be at least a full day. You dont want to ruin it now.

You can sand this now with a very fine grit to remove any imperfection in the paint if needed. If it looks smooth, no need to sand. After sanding up to around a 3000 grit sponge or cloth (never use sand paper as this bites into curved surfaces) use a tissue folded into a square pad to smooth out the paint. Rub hard into the paint, it does wonders so smooth it.

Now that is smooth, apply decals. I almost always use a softening solution - Tamiya mark soft, or micro set and micro sol, depending on any detail the decal sits on. The micro products are for getting the decal to conform to detailed surfaces. If the decal sits on a flat surface, you dont really need any softener, but it doesnt hurt.

When using the softeners I put a bit of micro set down on the freshly wet and applied decal - it help soften the decal, but also help with adhesion. Micro sol is used to really soften a decal. Once the sol is painted over the decal with a brush, dont touch it again. It will wrinkly up a bit, then lay flat as it dries. You can use a very soft brush dipped in the sol to paint over it a bit to help lay it down over raised detail. If the detail is quite raised, like rivets, I use an ear bud cotton bud thing to gently push and coax the decal to conform to the rivets. Practice make perfect doing this. You need patience too.


The tape on the bottom is to stop me knocking them over - its a narrow bottle.




You can cut or sharp pointy thing a decal to let the air out, then brush on more micro sol to help flatten it. Getting decals to look proper is critical to having the whole model look good, so practice a lot with the different solutions. If a decal is damaged from setting or sanding, you can use a fine brush and paint to repair it. Else sand or strip back to plastic, buy new decals, and restart - obviously not the preferred option. Tamiya Mark Soft is a much weaker version of sol, and can be used for decals that go on a smooth surface so you dont use all your micro sol when its not needed...

Once the decals are dry I mist coat a clear lacquer, which can be gloss or satin. Then another mist coat. Then progressively wetter coats, but still keep each coat thin. The lacquer and thinner mix will dissolve decals if its too wet at the start.

Keep the mist coat thin, doing successive mist coats until the decals are covered by the paint, and hold the airbrush away from the model so not much thinner hits the decals. Dont over do it at this stage or your decals will wrinkle. If you are using acrylics, you wont have this issue. Just use lots of thin coats like you did with the body colour.

After the mist coat is on, and decals covered with paint, spray on a few thinned clear coats that leave some wetness on the model. The wet coats should be very thin, dont spend to much time spraying one area or the paint will build up and run. The Mr Levelling thinner will help with this, as the paint has time to level out before drying, and sometimes what looks like a disaster, running or pooling paint, can sort itself out. Still, keep the coats thin, let them dry, apply another thin coat.

Now that theres a decent layer of paint over the decals, its time to sand back the gloss coat. The idea is to have the gloss paint thick enough to cover the decal so there is no visible edge of the decal seen in the paint. This is a process of lightly sanding using a foam backed fine sanding square, then spraying another layer of clear. Sand. Clear. etc etc etc. Go lightly with the sanding phase, you dont want to hit the decal underneath. Make sure you wipe off any dust with a lint free soft cloth once sanding is done. Make sure there is no dust on the body between coats - this means a close inspection. I use a cloth and a soft bristle makeup brush to remove the dust.

If dust or insects land on the paint while its wet, sand them off before another coat goes over it and makes it harder to remove. Make sure you inspect the body to ensure its free of these contaminates. If there is something in the dry clear coat, lightly sand it off.

Keep sanding, then spraying another thin coat until you cant see an edge on the decal after you have sanded. Different decals are thicker and thinner, so the amount of coats and sanding layers you do is up to the decal thickness.

Once the decals are level with with rest of the gloss coat (hold it up to the light and you'll quickly see if the paint is smooth or has an indentation at the decals edge) let the model sit for a few days or more for the paint to fully cure. The gloss coat must then be polished with finer and finer grades of sanding cloth, sponge, and compounds until you get the glossiness you desire.

Experiment and you'll quickly find out what products and techniques will suit your style.

Its a long slow process that requires many sessions and lots of patience. But if you put the effort in, your models will thank you for it.

Two products I havent yet tried for a super glossy finish are these, which I recently bought in Hong Kong. Im looking forward to seeing how they work, but look interesting. The wax can be put on any model, even rubber tyres, to keep dust and fingerprints off. Apparently.









These are race cars, so the paint wasnt supposed to be too glossy. I did most of the above technique to the cars, then finished by polishing with Blue Tamiya compound, and then finally a tightly folded tissue to dull it back a bit. Once the paint is done, you then start detailing the panel lines etc.

Sample car




sample car 2

[Phillip1]

cor-This is great information! Very detailed and exactly what I was looking for. Thank you for taking the time to post this information! Nice car models too!

Phillip1

[Tomcat64]

Thanks very much for taking the time to post this - really useful info, although the thought of sanding over the top of decals still gives me the jitters!

I love that Lotus in the last pic

[digger303]

What they said.

[aur0ra145]

This is an excellent write up!

[runnerUA]

Thank you for this. I have a car model that I can test this on.