Gloss clear coat drying like hard water stains

I was wondering if anyone could give feedback about a overall painting issue I am having that until I figure it out will stop my future weathering attempts.

I used clear coat testors over vallejo air paint last night and it is drying at whats looks to be water stains like you would get on an unwaxed car paint job.

Usually I clear coat the whole item when doing this. By chance I tested this piece to see how it would effect a build I have going on. I think I can repaint and save.

Is this or has anyone ever had this issue with gloss clear coat? This is my first time catching this. I really dont know if this is a norm with this product or any gloss clear?

I have to admit that I’ve never seen that before…

Were you using Testors Gloss Clear Lacquer? Any details about how you reduced (“thinned”) it and how you applied it?

I regularly use both Testors gloss and matt clear lacquers and find they behave very well… Just the same as pretty much any other lacquer paints.

On the other hand, were you perhaps using Testors Model Master Gloss Clear Acrylic? If you were, I might think this “beading” problem could be related to over-thinning with water. However, I must confess that I’ve never tried to airbrush the acryl clear gloss. I’ve only ever used it as a pigment fixer.

For gloss clear acrylic I use Future floor wax generally airbrushed neat from the bottle (although I do keep a small container of some thinned with just a little water for occasional hand brushing applications).

Maybe with some more details about the particular product and the application techniques, someone here can offer up some better ideas or suggestions.

@SdAufKla thank you for the response.

I should have said which product I was using.

It is the testors clear gloss laquer. I am about to do a swatch again just to test it against another of the same can. Maybe a bad can? Maybe it has always been that way and I only caught it because of the flat surface area of a wing. I usually shoot tanks.

I am using the gloss product out of spray cans.

Maybe Testors Lacquer Gloss in a can and Vallejo Model Air are not
compatible or that particular can has gone bad.
Just a thought.

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I just painted a swatch hastily in four quarters.

  1. Testors gloss older can
  2. Testors gloss brand new can
  3. Testors flat clear coat can
  4. No clear coat at all, just base flat black.

I just went back to look at a plane I shot last night in testors gloss and then later vallejo matt varnish. I can see the issue on the black. Actually I can it on the white and camo also on the plane. So I guess is has always been there. I guess this might be okay if always weathering item such as a tank. I just wonder what to do if Shooting a nice car model? Ill probably switch to future polish for now on. I have about half a dozen cans of laquer I guess

I will return to hobby lobby.

I am surprised I havent heard others talking about this or I just wasnt paying attention.

Well to me, it looks like the lacquer coat is crinkling the underlying paint
Maybe try using an acrylic gloss coat instead.
Hope it all works out.


I just read an article talking about shrinking on a different product and now wonder if thats whats going on here.

It seems that the lacquer reacts with the underlying paint, maybe the lacquer layer is too wet? … if the layer is too wet the thinner takes too long to evaporate and begins to reacts with the paint, how long do you give the acrylics to to dry?

This is a new one on me… As I said, I use both Testors gloss and flat lacquers, but I buy both in the bottles and thin with lacquer thinner to apply by airbrush. I guess it’s been probably back in the '70s since I used rattle can Testors Dull Coat.

A couple of things do come to mind, though. One is that the can needs shaking more and might benefit from warming up a bit before spraying. Try sitting the can in a pot of hot tap water for a few minutes. Your household tap water shouldn’t so hot that there’s any risk of overheating the rattle can. If it isn’t so hot that it burns your hands out of the tap, you should be just fine.

Anther thought is that you’re not spraying it heavy enough to self-level. It has to go down wet (not running or dripping, but still wet) with a continuous layer. If you’re just trying to mist it on, the droplets may not be running together on the surface before they start drying.

Wish I could offer up some definitive advice, but I haven’t actually seen this before with either Testors lacquer products.

I might agree with the others about incompatibility with the Vallejo paint except that your photo of the dried droplets on the decal suggest that this isn’t linked to the underlying coating.

@Vicious on all surfaces other than the test swatch it has been 2 days or more. the swatch was maybe 10 min.

I have gone back to looking at my other builds and see the issues on all of them. Ill try and take pics of it from other builds.

Again I usually paint the whole model at the gloss stage. So I never really had parts to compare with. sorta assumed no issues. I cant help but think others must be having this also happen to them?

if you have some other type of paint,Enamel,laquer or Tamiya kind of acrylics you can do a test to see if happen the same

Ps: SdAufKla I think he’s right I didn’t notice that it also has the same effect on decals, which takes paint out of the equation… :roll_eyes:

I am going to try on other stuff tonight. On top of primer, or spray enamel.

Its not as bad as the first pics seems to show. it just way more noticeable under a direct desk lamp above it. And with certain light temperatures. Very hard to notice when looking outside. I dont think its from not enough or to much clear coat sprayed either. Its not that big a deal just enough to keep me from ever using testors gloss again.

If you gloss, then jump into a filter wash you might not catch it or it matter like I usually do.

I just started doing some pledge test pieces and so far WAAY better.

A few other builds it shows up on. If I filter with oils or other weather probably no biggie. Just if I go to do a auto its a pretty big issue.

I could get similar effects with Johnsons floor polish diluted with water when I airbrushed it from too much distance and with too much air (lean mix). I did it intentionally to get a slight satin effect before doing a wash. Similar results using Tamiya gloss clear with those “bad parameters”

Robin I have wondered if it was a distance thing or humidity or temp or ? I was wondering orange peel. I just thought orange peel was a different condition than this.

I have built about 20 using the gloss in the last two years and they all have it.

I am open to what I might be doing different or wrong to cause it.

I can’t say what is or isn’t causing the problems. One possible way to find out is to test different variables one at the time. Maybe you could find the solution that way.
Pressure, ratio of air to paint/lacquer/polish, spraying distance, time “on target”, underlying paint.
If you use a rattle can you can only change the distance and “time on target” / how fast you move across the surface. The surface could also be varied, use another acrylic or use an enamel just to check if the lacquer attacks the acrylic.

My GUESS is that the lacquer doesn’t go on wet enough, i.e. distance and/or linger time. Only a guess though so you need to test.
I have never used that type of rattle can (only used rattle cans three times the last 50 years except for shoe care products…) so I can’t comment on how well/bad they spray. My gut feeling is that an airbrush behaves better …