Flat Black for the last time

Maciek wrote: .

What DOES make a difference, however, is how wet you apply it. With a brush this is just technique. For an airbrush it depends on pressure and rate of application. I use a higher pressure for flats, which allows me to back off a bit- the further you are from the workpiece the dryer the coat you put down, and the flatter it looks. You don't want to allow it to get wet, as it will dry semi-gloss/semi-matt then.

You probably misunderstood the mixing instructions. I would say that 1 minute and 10 minutes of shaking would both be thoroughly mixing the paint.

If you let the paint bottle sit for few days, then shook it up probably using like 10 or 20 shakes (not a full minute!), you would end up with a less flat finish.

The flattening agent settles down on the bottom. If you don't fully mix it back into the paint, you end up with less flat finish.

Also, any flat finsh is prone to what you call "autowither". That is just a nature of flat paints. And more flat it is the more prone it will be to it.

It is caused either by the oils from your finger getting deposited on the surface (making it shiny) or by actually physically removing the surface roughness which makes the paint flat. If you were to look ar the surface of flat paint under magnification, it is very rough. If you remove that roughness, it gets shinier.

Peteski

There have been a lot of comments on "shaking" the bottle to mix the paint. Personally, I think stirring is a far better way. I can definitely say that you can shake a "tin" of Humbrol till the cows come home and still improve it with stirring!

Also, shaking tends to aerate the paint and, although I can't quote the source or swear to its accuracy, I've heard that shaking is not good for acrylic paints.

MB

Too true! I'm not a big fan of stirring paint as, like Tim Taylor, I want "more power" motorization and that winds up a splashy mess. If I've got a paint that doesn' t want to mix well I stick a bb or, even better, a tiny hex nut in it and set it on my case tumbler for about ten minutes. Awesome! Thirty year old paint looks like it just came out of the factory. You can also use an orbital sander for this. Cheers, The Keeper

Years ago I saw a paint rack that was motorized. It was sort of a drum-shaped thing. You hooked the bottles on via their tops. The drum slowly revolved. I'd think that would help. To cut down stirring time I take the paints I will use on a project and keep them top down on bench till I mix them.

The problem with that rack as I see it is today there are such a variety of paint bottle sizes, with caps of different sizes, so don't know how well such a rack would work, but I have been tempted now and then to build one.

:) Regardless of mixing / shaking alhorithm / problems - I posted this message just to summarize 'flatness' differences in acrylic paints which turned out to be big.

Maciek

and an electic jig saw. shake it, baby!