Paint bubbling

[Bill_S]

A question for the group - have you ever had this happen to you?

One of the wings from my WNW W.29 - I painted using Sovereign Colourcoats CDL enamel. The enamel has cured for over a month. A light spray of Model Master gloss produced the same effect in places on the ailerons. On the wing, I could not get the cross decal to sit down - I had a big air bubble where under the decal; after several attempts to fix it, I decided to strip the decal, mask and paint the cross. A light spray of Tamiya white primer gave me the situation in the picture above.

I've sprayed lacquer gloss over just about everything in the past and have never had this happen.

[Jeff]

THAT sucks !!!  Is it repairable or do you have to strip it completely and start over?

[DocRob]

I never discovered something like that, but I also never used Tamiya (rattle can?) primer over an existing paint coat. Taking into account how the stuff smells, I think it's very aggressive and might interact with sub layers. Interesting, that the problem does occur only in parts.

Cheers Rob 

[Bill_S]

I am quite perplexed, Rob. It happened in spots with lacquer-based clear gloss overcoats as well. For the next round, I'll probably go with Tamiya gloss white. I wonder if it's some kind of incompatibility with the Sovereign Colourcoats formulation...

[Bomber_County]

What is the base of Sovereign, dare bet it’s a weird hybrid.......I know Vallejo and AK extreme metals dislike each other.......

[Bill_S]

31 minutes ago, Bomber_County said:

What is the base of Sovereign, dare bet it’s a weird hybrid.......I know Vallejo and AK extreme metals dislike each other.......

Phil, it's supposed to be an enamel. The paint is, from what I've read, highly regarded - and there are a couple of colors that they carry that you can't get elsewhere (French Midnight Blue being one of them).

About five minutes of work with Mr. Color thinner...

We'll see how this works... I don't want to have to strip the whole thing - there's some expensive Aviattic naval lozenge on the other side!

[krow113]

I know its tough but sticking with one manufacturer is a good policy.

Sealing in between with an acrylic clear is a good idea too.

 

[JohnB]

I don't think I've ever encountered that problem. Bummer! My choice of paints has long been enamels and Alclad which might have something to do with it. Good luck straightening it out!

[GazzaS]

Tamiya and Testors do not get along.  If you paint Tamiya over Testors, you get problems.  You can put Testors on Tamiya...  but Tamiya on top will always attack the Testors. 

 

Learned it the hard way quite a long time ago.  I have seen it mentioned before... but not much lately as fewer and fewer modellers use Testors.

 

Gaz

[Bill_S]

19 hours ago, krow113 said:

I know its tough but sticking with one manufacturer is a good policy.

Sealing in between with an acrylic clear is a good idea too.

 

I have been known to do just the opposite. On my Tamiya F-4J, I sprayed the instrument panels Tamiya semi-gloss black. Once cured, I oversprayed with Model Master gray enamel. Once the enamel was dry to the touch (but not fully cured), I used paint thinner to rub the enamel off the high spots. The paint thinner won't touch the acrylic layer underneath.

7 hours ago, GazzaS said:

Tamiya and Testors do not get along.  If you paint Tamiya over Testors, you get problems.  You can put Testors on Tamiya...  but Tamiya on top will always attack the Testors. 

 

Learned it the hard way quite a long time ago.  I have seen it mentioned before... but not much lately as fewer and fewer modellers use Testors.

 

Gaz

Gaz, is that Testors enamel or acrylic?

[GazzaS]

Enamel

[krow113]

To keep compatibility you can also spray sample cards of specialty colors and mix match's from the compatible paints.

[1to1scale]

From the wrinkling effect, it looks like the solvent of the paint underneath caused the top layer to lift and swell 

[1to1scale]

On 10/23/2020 at 8:37 AM, Bill_S said:

I have been known to do just the opposite. On my Tamiya F-4J, I sprayed the instrument panels Tamiya semi-gloss black. Once cured, I oversprayed with Model Master gray enamel. Once the enamel was dry to the touch (but not fully cured), I used paint thinner to rub the enamel off the high spots. The paint thinner won't touch the acrylic layer underneath.

Gaz, is that Testors enamel or acrylic?

This is an excellent idea.

[ScottsGT]

Never spray lacquer over anything but lacquer.  It's a very "hot" paint that strips enamels.  Back in the day the bodyshops had the same issues back before the basecoat/clearcoat systems used now.  Cars use to come with lacquer from the factory and paint and body guys used lacquer to touch up and make repairs.  When the factories transitioned over to acrylic enamels, some of the old school guys refused to conform to the new paints and they had a hell of a time blending paint.