Best way to avoid and fix frosting on matte topcoat

[hd3]

So I accidentally  got some white glooping after applying the topcoat to my necron. Im fairly sure I messed up the top coat. Can anyone tell me how to fix and avoid this in fiture?

[Karhedron]

What topcoat were you using?

[Firedrake Cordova]

Having a "frosted" finish to a surface varnished with a matte varnish is due to the varnish drying to a rough finish - this is normally caused by excess humidity, or not mixing the varnish well enough.

You should be able to fix it by painting the area with a satin or gloss varnish (this should dry smooth), and then re-coating it with matt to get a uniform finish.

Example video showing the issue and fix, and another video with a more indepth explanation of why.

Tangible Day has a blog post explaining the issue in more detail if you'd rather read than listen.

Edited October 11, 2022 by Firedrake Cordova
improved clarity

[hd3]

4 hours ago, Karhedron said:

What topcoat were you using?

mr hobby top coat flat

[Karhedron]

46 minutes ago, hd3 said:

mr hobby top coat flat

OK, so a spray. In that case, as Firedrake Cordova mentioned, you need to take care to avoid humidity. Frosting (or blooming) is usually caused by moisture in the air getting trapped in the spray. Take care to spray only on dry, fine days and avoid early mornings or evenings where temperature changes can cause the relative humidity of the air to rise.

Also shake the can thoroughly for at least 2 minutes before use to ensure the contents are well mixed.

[apologist]

@hd3 – sorry to hear about the frosting problem! I had the same thing happen to my Gatebreaker Chaplain, and happily, it's fairly easy to fix.

@Firedrake Cordova's method will work beautifully; and I'd echo @Karhedron's advice on thoroughly shaking your varnish – not enough agitation is what happened to my Chaplain below.

If you fancy another approach, you can brush on some drying oil, such as linseed oil or walnut oil. The problem will be fixed immediately, but you'll need to wait a few days for the oil coat to 'dry' (oxidise).

It's important to use a drying oil, as something like sunflower/olive oil will go rancid; and mineral oil won't oxidise (and so won't ever dry).

Before:

 

During:

 

After:

I wrote an article about it here if you'd like to read about the process in more detail, but rest assured it's quick, cheap and easy to fix.

Edited October 11, 2022 by apologist