Clearing over decals

[Patrick K.]

I normally build factory stock and am working on a '32 Ford rod as we speak. Never applying decals on a body too often, is it ok to spray automotive clear over them. What are the pros and cons (if any) to different clears over decals. TIA

[Moon Pie]

In my experiance, automotive clear coat is too "hot" for the decals. I've always used Tamiya or Testors clear laquers. To be on the safe side, you can airbrush Future as a clear coat, and remove it with Windex if you mess up.

[Pete J.]

Been using DuPont clear lacquer for years and never had any serious problems. Use a cool thinner(fastest evaporating) and spray it thin the first couple of coats. I use 5 parts thinner to 1 part paint. Let it set for an hour then a second light coat. Sit over night, then you can lay on more coats 15 to 30 minutes apart. No such thing as a wet coat. Lacquer needs to be rubbed out. Part of the design. Don't wait to long or it will get harder than *****, well, you know.

[Ddms]

Interesting that you can get Dupont lacquer where you live. Here in California, traditional lacquer is seriously illegal, and no automotive paint jobber dares sell it. One store told me that a shop had been closed down for importing it from Nevada. I did a lot of shopping around in the L.A. area, and the only place you can get a bottle of genuine clear lacquer is at a hobby store! And that's Testors Glosscote. Of course, Tamiya TS13 and MM Lacquer System clears are available, but only in spray cans. Both of those are synthetic lacquers that don't have environmental issues.

Automotive paint stores do sell Dupont 2-part urethane automotive clears, which are not lacquers, but they don't sell them in small quantities. Expect to spend a minimum of $40 for a 2-pack including the coating and the hardener. As far as I know, Zero Paints from Hiro (MFH) are the only urethane clears available in small quantities.

They give you a terrific gloss; some people like that, but for the cars I build, it's too extreme. And there are other drawbacks. Urethanes tend to collect near edges and panel gaps, giving the car a dipped-in-syrup look - it's called the meniscus effect. (This is more noticeable in small scales.) Unlike the syn lacquers, urethane coats don't blend one to the next. For example, if you sand through to the color coat, you can't just re-clear the burned-through area. The "patch" will show. They are also very tough and difficult to strip. There are also safety issues. At the very least, you need to wear a professional respirator when spraying urethanes.

Actually, many modelers - including me - have had problems spraying Tamiya TS13 over decals. It depends on the decal, of course, but you can't be sure until it's too late. So it's essential to start with two or three very light, dry coats, and even then, don't apply it too wet. The same applies to U-POL Power Can, which is the same as TS-13, except much, much cheaper.

OTOH, I don't think there's a problem spraying urethane clear over decals. I've heard that they are much milder than the synthetic lacquers, but can't say that from a lot of personal experience. I've only used 2K clear on a couple of cars, and the decals have not been damaged.

Edited September 5, 2009 by Ddms

[chris coller]

I have just purchased PPG 2 part urethane clear and have been experimenting with some old bodies and have found no issues going over decals. As far as the TS-13 the only decals I have had no issues with is Tamiya's own decals. All other decals need to be built up over 5-8 light mist coats to help "seal" the decals before you start laying heavy coats. Hope that helps.

[Patrick K.]

Thank you all very much! I really appreciate all of your time to answer my questions. You've been a great help!