Why my paint somehow became shinny???

[Calimero]

It seem that, with the time, quite a few of my flat (mat) paint somehow became shinny… 

Do anybody know why this is happening? Could it have to do with temperature change? I paint my minis right beside the windows to get as much natural light as I can. It can be both an hot environment if the sun hit the windows or became quite chilly from time to time if the windows is open (I live in Canada ). Is it because I don’t shake enough my paint bottle before use? I have this problem with Coat d’Arms, Vallejo and GW. It’s less of a problem now because I mix some Flat Base from Tamiya to the paint. I really like the Coat d’Arms and Vallejo paint and I will continue to buy them both. It's just that I would like to know if I’m doing something wrong and, maybe, to save me the trouble of mixing in flat base.

[argsilverson]

Your problem seems to be a common problem. In the theory of paint making it is said that raw materials [resin and solvents applied] do produce a shinny or better glossy effect. To reduce it and also produce real matt paints, paint manufacturers do add solids that pevent gloss. The most common raw material used is talc.

The problem you are facing should be created by the following reasons:
.- producer has not manufactured well the paint you have bought. Please concider that there a conciderable difference in the quality from batch to batch. That means that the paint you bought last week might be slightly different, in some respect, to paint you bought today.
.- the paint has "sat" after the time it is in the vessel.
.- the paint is not stirred well.

It has nothing to do, in general, with temperature.

Some solutions:
.- The obvious solution could be, try to add some talc in your paint (max. 2-3% w/w). Since the hobby paints have very small particles (to improve flowability, covering and hiding  power, etc] it is very hard to find easily available talc so micronised. On the other hand you also need to stirr your paint at very high speed, so the talc could be dispersed evenly. I used to use baby powder [= micronised pharmaceutical talc] with good results, but with humbrol enamels and not acrylic paints.  So I do not suggest to use the talc option.

.- the other solution is to shake/stirr the paint very well. I doubt that it will improve the quality paint, but it helps.

.- So, we come to easiest solution: Ignore the glossy effect during painting, finish your minis and then cover them with a very thin film of matt transparent varnish. I think that will solve the problem.

.- But I suggest not to mix flat base in your paints. This might ruin your paint, due to incompatibility. In fact since we do not know exactly which chemicals each company uses it is better not to mix paints and varnishes of one manufacturer with paints etc of the other. Also, if you use paints by different producers, wait until the one layer is completely dry, and then apply the new one. Watch if you see any problems before you go on.   

Hope to have helped you in some way!

[Plynkes]

Being someone brought up on enamels, I have found since switching to acrylics that they are almost always shinier than I'm used to and would like.

So I don't worry about it, and rely on my final varnish coat to get a nice matt finish. The problems start for me when the varnish decides to play up (which it did this week!  ).

[argsilverson]

Being someone brought up on enamels, I have found since switching to acrylics that they are almost always shinier than I'm used to and would like.

So I don't worry about it, and rely on my final varnish coat to get a nice matt finish. The problems start for me when the varnish decides to play up (which it did this week!  ).

Yes, resins and solvents used in enamels are naturally more glossy than the more modern resins used in acrylics.

Usually your problem with matt varnish can be solved by careful stirring, unless you use not compatible varnish.

Did you get white spots?

[Plynkes]

No white spots, just shiny instead of matt. It was spray varnish, so stirring wouldn't be an issue, though humidity might have been. The odd thing is that I sprayed a bunch of units and the first half were fine, lovely and flat, but the second half came out all shiny. And this all from the same tin and done at almost the same time. 

[argsilverson]

No white spots, just shiny instead of matt. It was spray varnish, so stirring wouldn't be an issue, though humidity might have been. The odd thing is that I sprayed a bunch of units and the first half were fine, lovely and flat, but the second half came out all shiny. And this all from the same tin and done at almost the same time. 

Several reasons:
1.-  Never trust a spray. Better brush and liquid varnish.
2.- do not use the spray on lots of figures. usually the first half is OK the second half has problems. Some of their components are lighter than the others and usually come first.
3.- hummidity might create problems, but usually in very thick layers and also when long drying time is involved. [ i.e. If you spray furniture yes, if you spray miniatures I doubt].

Suggestion make one mini by the time and repeat when necessary with fresh spray.


Furthermore, please check whether the shiny figures were painted with same paints like the others or not. If not then you might face a slight incompatibility problem.

[Mindenbrush]

CDA, Foundry and some Vallejo Game Colour paints tend to be a shiney finish no matter how much you shake them.

With the spray vanish if you are using Dulcote then it is advisable to warm the can and the figures on a radiator or similar, shake the can well and then spray.

[Cosmotiger]

Plynikes,

Whenever you use a spray clear coat (or primer), shake it two minutes. Two FULL minutes, I mean. Use a clock with a second hand, or set a timer.  That (along with warming up the can in some warm water before shaking) will work wonders. 

Humidity and overly thick coats can also cause flat varnish to become shiny, too.  Those are hard problems to overcome.  I've found that sometimes if you let the figures sit for a week or two, until they cure totally, you can lightly spray on more of the flat coat, and that can kill some of the shine.  You might not ever get them dead flat, though.