A couple of times now I have used the Mr.Hobby acrylic matte clear finish and have noticed, upon drying, that some very small white flecks appear on the surface of the model. As mentioned they are very small but definitely a distraction. I normally thin the product with isopropyl alcohol so am I doing something wrong ? Thanks

Frosting usually happens when the paint is dry before it hits the surface. You could try lowering your air pressure and thinning a bit more. What ratio are your using?

Frosting happen also if you dont shake very well the paits

Hi. It's not frosting, it's very tiny white flecks. And they have only ever appeared when I've used the matte flat product mentioned.

I assume you've successfully used such combo / mix without issue till now. If so then potential culprits may be:

- the matte coat you have has gone bad, or
- there was a change in the specific alcohol you've used, or
- the matte coat + alcohol wasn't thoroughly mixed

I don't have direct experience with the product you use as I do my flat coats using Future + Flat Base. And whenever I get those white spots it just means that the mix wasn't that thorough so I'd just do a second pass making sure it was well mixed.