Issue with Tamiya TS-13 Clear

[av405]

Just to give some background: I went through the usual recommended stages of sanding, washing, cleaning etc. with this model that I've gone through many times before. I then applied the following products (all Tamiya): grey primer, white primer, pure white paint, black paint. Everything went well until I applied TS-13 clear, a week after the black had dried (per Tamiya's own recommendation). Overall, the clear laid down smoothly but for some reason, the following issues appeared only on the front of the body. The first picture has white almost appearing to run down from the headlight area. Then there is a random white square that appeared on the corner. 

 

Then there is this corner. Originally there was a clearly defined sharp border between the black and the white. After the clear, the definition was lost and the white smudged into the black and a faint black circle appeared where the white was.

The only thing I did differently from past times was laying down the clear a week after the last paint coat. I've heard that you have to lay it down either immediately after the last paint coat or wait a month or so to spray, but I went down this route following Tamiya's own instructions. Was that the culprit here? Or is there another possible explanation? Thank you in advance. 

[Sandboarder]

My assumption would be the clear coat was too heavy. The wet clear coat reactivated the base coats (did you spray black over top of pure white) and have melted or dissolved it. Kinda like spilling some lacquer thinner on the edges of the black paint. 
 

I usually wait a week or more for this reason as the previous coats still gas (rattle cans) and dry/harden fully. 

[peteski]

Does the black paint layer on the front bumper look like it cracked and shrink a bit, exposing the lighter colored paint under it?

[av405]

Thanks for the reply. Yes, I sprayed the black over the white.

I waited a week in between the black and the clear, so next time I will wait two weeks. Come to think of it, I could have just sprayed the clear immediately after the black as the white was already hardened. The more you know...

[Michael jones]

Very easy to fix by spraying the black over again in those areas carefully. The clear was applied too heavy so it melted the below paint. 

[happy grumpy]

I use Tamiya paint a lot. This happened to me before. I found out that even If you wait days, Like Chris said if the coat is too heavy it will sink in the paint. I had a monte carlo all finished and when I applied the clear , the next day the thin decals were running down like they melted.

What I do to avoid this;  Apply 3 or 4 very thin mist coat to seal the underlying paint (especially if you have decals), 10-20 min apart, let it rest for a few days, wet sand if you want, lay 2 or 3 wet coats and let it rest for a week, then depending on the finish I want, I wet sand and polish. The thing I do now is to prep and paint  the body long before I start building, I always have a few projects to work on . One last thing, lacquers dry fast but they seem to take some time to fully cure. I had a few occasion when the paint did not play well with the plastic even when de greased, primed and sanded, this happened only in recent Revell kits where the plastic had an uneven sheen and it would show thru the paint even after 3 or 4 coats of paint. 

 

Sorry for the long post , hope this helps

[Bainford]

1 hour ago, happy grumpy said:

I use Tamiya paint a lot. This happened to me before. I found out that even If you wait days, Like Chris said if the coat is too heavy it will sink in the paint. I had a monte carlo all finished and when I applied the clear , the next day the thin decals were running down like they melted.

What I do to avoid this;  Apply 3 or 4 very thin mist coat to seal the underlying paint (especially if you have decals), 10-20 min apart, let it rest for a few days, wet sand if you want, lay 2 or 3 wet coats and let it rest for a week, then depending on the finish I want, I wet sand and polish. The thing I do now is to prep and paint  the body long before I start building, I always have a few projects to work on . One last thing, lacquers dry fast but they seem to take some time to fully cure. I had a few occasion when the paint did not play well with the plastic even when de greased, primed and sanded, this happened only in recent Revell kits where the plastic had an uneven sheen and it would show thru the paint even after 3 or 4 coats of paint. 

 

Sorry for the long post , hope this helps

Thanks for this, Mario. I very rarely shoot clear, but my current project has a lot of delicate decals, so I will be laying some Tamiya lacquer clear on it tonight. I've been nervous of this, since I have heard horror stories of Tamiya lacquer clear eating decals, and also my overall inexperience with shooting clear. I'll give your process a try.

[av405]

Thank you all for the replies. I definitely went to thick on the front with the clear. Thankfully I didn't do this for the rest of the car. Some touch up painting should do the trick. Thank you.

[Dpate]

Just now, av405 said:

Thank you all for the replies. I definitely went to thick on the front with the clear. Thankfully I didn't do this for the rest of the car. Some touch up painting should do the trick. Thank you.

Yeah with clears especially like 2K clears you wanna lay a light tac coat so the other coats have something to stick too better.  You don't have to do heavy coats of clear though.  I use a lot of scale finishes base coat paints and with there paint and your choice of clear coat you could be done painting and clear coating in like 2 hours.  Gravity colors(spain) 2K is a awesome clear too.  You don't have to do mist coats and wait days before doing wet coats that's just silly.  A tac coat is just that a tacky coat.  After 10-15 mins it should be ready for your next coats.  This is speaking based on 2K clears because I've never used tamiya's clear before.

[Sandboarder]

I always use TS-13 I apply clear after a few days or a week. (I do interior or chassis work while I wait) With my clear coat I do a light mist coat, wait 3-5 minutes for it to flash off and then lay my final coat of clear.