Tamiya Clear coat eating paint underneath?

[defiantworkshop]

OK, started my first model car this weekend, the Tamiya Morris Mini Cooper 1275s. This was a "trainer" car, something to start and learn on. I sprayed on plain old Tamiya gloss red, X-7, a few thin coats until it got nice and even. Let it dry overnight, and applied the decals (with a little difficulty, but that's another matter). After the decals had dried, I sprayed with with a super quick mist coat of rattle can gloss from Tamiya. It was definitely a mist coat, not real heavy, no drips or anything. It took almost no time for the paint underneath, especially the paint in crevices, to eat away and show the primer underneath (see attached photo).

So what did I do wrong? Need to wait longer for paint to gas out before clear coat? Avoid Tamiya clear and use something else? Need some guidance. Sorry if this is  repeat question, thanks in advance for reading and helping!

[GeeBee]

When you say you sprayed the Tamiya X-7, was this out of a rattle can or airbrush ?? Also I'm not sure why you would need a clear gloss over gloss paint 

[Exotics_Builder]

Looks to me like the Red had not cured long enough and the solvents in the Clear dissolved the Red where it was thin

Same here.  Assuming your X-7 was the rattle can lacquer?

[DON-T2]

Isn't the X-7 the bottled paint? I believe they are a acrylic paint that would not be compatable with TS-13 clear coat. Please correct me if i'm wrong.

I have used TS-13 for several years and never had a problem over the Tamiya and Model Master lacquers Also have used Mr. Hobby clear with no issues.

[defiantworkshop]

Thanks for quick replies...

X-7 is indeed bottle paint, not rattle can. So TS13 is NOT compatible with their bottle paints??? I tend to not use rattle can if I can help it, just b/c I don't have enough control. The few times I"ve used it on other kits I've done, the slightest error gives drips and runs, so I spray as much out of my airbrush as I can.

I used clear gloss over it b/c the gloss from the red itself doesn't have enough shine, and putting decals over the gloss paint made it look funny. It was to unify the finish.

 

 

 

[Ace-Garageguy]

The materials you're using aren't in my particular arsenal, but your problem is another very good reminder of why it's so very necessary to practice and test materials for compatibility BEFORE committing to painting a model.

I keep several old bodies around and repeatedly strip or re-primer them just for this reason. The extra work saves a lot of disappointment when it comes time to paint an important model.

If you don't happen to have extra bodies, a plastic soft drink bottle, scuffed and primered, makes a very good practice / test substitute. 

[Longbox55]

Plastic spoons are also very good for doing paint testing.

I do agree with the others, you have a compatibility issue. Since you are working with an airbrush, you might consider using Tamiya X-22 Clear Gloss, which is part of their acrylic line.

[defiantworkshop]

This was a test piece of sorts, so no real worries there. I have a closet full of cars that I WANT to do, and picked this up since the decal work was simpler than the other rally cars I have...so I'm not really all that miffed by it. It was designed to be a learning experience.

OK, so use rattle cans for rattle cans and X series for X series. Got it. Really odd, I thought I read somewhere that somebody was using TS13 as their top coat after airbrushing standard stuff. No worries at all. I'm actually far happier its a general consensus compatibility issue, rather than a technique or innate talent issue.  Thanks crew!

Edited March 30, 2016 by defiantworkshop

[Exotics_Builder]

TS-13 is lacquer and X-7 Acrylic.  NOT COMPATIBLE.  The Acrylic Gloss Clear is X22, I believe.  In my experience with their acrylics, many dry semi-gloss and would need a gloss coat (also to protect decals).

[defiantworkshop]

Cool. So let me ask this....I see a lot of people say they don't have that in their armory of paints. What are you all using? Rattle cans? Different brands? Options here in Alabama, as far as LHS, are pretty limited, and the select few still in business only sell Testors and occasionally Tamiya.

[Longbox55]

Well, just speaking for myself, my arsenal of paints is very well stocked with just about any kind of finish you can think of. Everything from Testors enamels to real car paint. I can tell you that sometimes you have to think outside to box a bit on paints. There's several lines of paints out there that can be used with modes with the proper precautions. Duplicolor, Rustoleum, and a few other brands of spray paint can be used with the proper primer. Speaking of primer, Duplicolor has several good lacquer based primers that work well with model car plastic. Their primer and paints are readily available at most car parts stores and some big box retail stores. Some builder have had good results using water based craft paints. Since you are airbrushing, another great source is fingernail polish. Lots of usable colors available, and with a little lacquer thinner, they spray very nicely. I'm partial to the Sinful Colors line myself, mainly due to their availability, color range, and most importantly, price.

[peteski]

As it has been said, Tamiya paints in litle glass jars are colloquially known as water-based acrylic enamels.  But in reality the solvent is not water but isopropyl alcohol, which is a mild solvent.   Those paints in my opinion they are more like a lacquer than enamel. Spray cans OTOH contain "hotter" lacquers based on stronger solvents like acetone.  Because of that, the hotter paint applied over the milder paint will most likely cause problems (as you witnessed) because the hotter paint's solvent can re-dissolve the milder paint.

As far as what brands of paints I use, I have been in the hobby for decades so I accumulated a large stash of paints.  Testors and Model Master, Humbrol, Pactra, Floquil, Polly-S, Accu Paint, Tru Color Paint, Tamiya, Gunze Sangyo, Alclad, Metalizer, and several other brands I can't think of right now. I also have cans of household spray paints like Rustoleum. I have hundreds of bottles/tins and dozens of spray cans.  I prefer airbrushing so most of the spray can paint gets decanted for airbrushing.

Here is my paint cabinet. All the drawers are full of paint bottles and the larger lower drawers hold spray cans.

 

[snacktruck67]

I have found a formula that works for me.  After the paint has dried for a few days, I scuff the paint with some 3000 and 4000 wet and dry sand paper.  I use them only in the wet mode.  I get an even haze all over.  Not rubbing hard while sanding, but very light.  Just enough to haze it.  Then I apply 3M's Scratch-X.  I rub it all over the body, section by section.  I do a lot of rubbing, as the Scratch-X is a mild abrasive.  After several minutes of rubbing I buff it off with a clean lint free cloth.  It should have a fantastic shine at this time.  If not apply more and continue light rubbing.  Once you have the shine back, apply a coat of McGuire's cleaning wax to the model and buff that off.  Then once that is done, rub in a generous coat of McGuire's Carnuba wax all over section by section. Buff all that off and you should have a super smooth shinning model.  Repeat as needed, if you so desire.  I find that I get a super smooth and highly polished model.  It rivals any spray on clear coat.  I have compared my finished model with the clear coated ones, and I am very satisfied.  Try it sometime, I think you will like the end results.  Sure there is a lot of rubbing involved, but it is worth it.

[Mike_G]

I've used TS-13 over Tamiya acrylic without any problems, but only over small touch-ups.

[DanielG]

TS-13 can provide some very 'interesting' results. The most common mistake is to spray it on too soon, even over Tamiya lacquers. Even if it does not attack the base material it can crack, showing up days later. Very annoying!