Varnishing with airbrush issues-help-Updated

[Defiant911]

I’m a newbie to the modelling.
I have a dual action airbrush which I have been using for the first time to spray paint my models. Painting has gone very well and the finish has been great but whenever I airbrush the varnish (humbrol clear gloss varnish) I keep getting a very mottled and patchy finish which frankly looks awful. I’m spraying at around 18psi pressure from and inch or two distance away from the model. I have attacked a picture showing the type of poor finish I’m getting. Can anyone offer any tips how to correct my mistake please.
carl

[Guest]

Did you clean the surface prior to varnishing? Looks to me like the surface was greasy prior to application.

[Defiant911]

Did you clean the surface prior to varnishing? Looks to me like the surface was greasy prior to application.

I have done the weathering and then wanted to seal it all in. I thought it was ok to spray a varnish layer after weathering? Is theee anything I can do to repair the finish? Thanks in advance.

[Guest]

Yep, you should have been. The only other ting I would be worried about is whether any thinning agents were used that could have affected it.

I can't think of anything mechanical that would have caused that, so I'm at the limit of my experience there I'm afraid.

Hope you suss it out.

[Guest]

Just thinking....what are the weathering products you used? Are they oil based, or oil paints?

[rtfoe]

Carl, clearly there is a reaction from the previous paint or weathering material with the varnish. Can you list the types of paints used as whether they are oil or water-based including the varnish plus the length of time in between application?

Cheers,
Richard

[Defiant911]

I sprayed a thin coat of varnish after competing the painting in acrylic reveal paints. I used the ak panel liners (Ak2070) which I think are oil based. Given that I have sprayed the model Initially with acrylic paints would this be an issue I hadn’t considered. My in experience thought these were ok to use over acrylic paints? Should I be using something else to weather my models?

[Defiant911]

Carl, clearly there is a reaction from the previous paint or weathering material with the varnish. Can you list the types of paints used as whether they are oil or water-based including the varnish plus the length of time in between application?

Cheers,
Richard

As mentioned, revel aqua paints and ak weathering. Using the humbrol clear gloss varnish. Quite a combination

[Guest]

Oil on water based would be fine. Not the other way round.

[Defiant911]

As mentioned, revel aqua paints and ak weathering. Using the humbrol clear gloss varnish. Quite a combination

Oh, I left the Modelmover night from the AK weathering before applying the gloss varnish so about 14 hours ?

[rtfoe]

Is the Humbrol clear varnish oil based or waterbased?

[Defiant911]

Another picture although I’m not sure how clear this has come out

[rtfoe]

With all that weathering can't see the varnish effect except it could look like morning dew on the tanks surface.

Cheers,
Richard

[Defiant911]

With all that weathering can't see the varnish effect except it could look like morning dew on the tanks surface.

Cheers,
Richard

It certainly looks a bit like dew although that was not my intended effect. Out of curiosity what is your general application when applying varnish, e,g, psi from compressor, distance from model with airbrush and general motion applying it? Just wondering if it’s part to do with my setup and application. As I say, this is only my third model sim I’m very much learning from my mistakes.

[Jack L]

In my experience, gloss varnish does tend to 'pool into globules' slightly...and you have to apply a bit more than you feel is fight to get an even finish. I might be doing something quite wrong, but have only had one issue of spraying too much, where it ran off. Matt varnish (for me) reacts very differently and I spray pretty sparingly.

PSI, I just guess until the flow looks right, as with the distance from model, depending on the surface area, but I would say 3-4 inches away. I use a slow sweeping method back and forth, starting and finishing away from the model.