Question for the "paint experts"

[Dragonfly]

Why can't they either :

A) Make regular spray paint act like primer

or B) Make primer in a wide assortment of colors

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?


You can spray primer on thicker with less chance of dripping, it's sandable, it dries fast, etc.... When I do white pedals I use white primer with a clear coat over top...it just looks better and goes on with less effort....

[John Lyons]

Primer has more solids (particles) so it's thicker and dries flat (matte).
Let's see...green, white, rust, black, grey...I think that's all the primer colors I can think of.

Most people want the gloss or "regular" spray paint....

The matte/flat spray paints are faster drying.
Lowes has the new Valspar brand sprays in some
nice flat colors. A decent price as well.

[Dragonfly]

Thanks John -

I've seen red primer as well.

The "matte" finish looks like gloss as soon as you spray clear on it ...plus it cuts down on painting time by a TON !

I've used some of the Valspar colors - good stuff - i'll look at their primers as well...

[jakehop]

Hi Andy,

If you use an airbrush, you can mix certain colors with your primers to get a hybrid. I use that, and it's almost like the best of both worlds - I have to spray a lot before it drips!

Kind regards, Jake

[Dragonfly]

Hi Andy,

If you use an airbrush, you can mix certain colors with your primers to get a hybrid. I use that, and it's almost like the best of both worlds - I have to spray a lot before it drips!

Kind regards, Jake

I'm not on an airbrush, though i've considered getting one - maybe after Christmas...

I hadnt thought about mixing them...thanks for the tip !

[frank_p]

Yes like John said. the primer is a "thick heavy bond" thing.  That is the concept to have in mind.  If you want to use primer with colors, you can even make your own I think.  The problem is that it is almost of the time "close pale" so very "cheezy".  The reason is that it have a high content of chalk.  Just like in cheap painting, the colors will be "faint".  There are books on making your own primer, paints, and others to have all sort of properties.

Basic:
- it has to hide properly (chalk or other particles)
- It has to bond to the desired material, this is why there are so many kind or primers. (Can contain glues, volatile acids, a lot of "bonding" material...)
- It has to not dissolve in the other paint that you are going to put on it, but still provide a good bonding surface.
- it has to be matte for better adherence.

So given all those properties, most of them will not bear a high content of color pigment because: it's lost money.  Pigment is what cost the most in paints.

Here is an article on gesso, which is a primer for canvas.  It's not the same thing, but it help to understand the concept of primer, and what you can do whit it:

http://en.espritcabane.com/paint-recipes/gesso-patina.php

[m-theory]

You could visit an auto paint store and have them mix up whatever colors you wanted in lacquer, and have them add a flattener to the paint before they inject it into the spray bomb cans.  It would cost you $$, but you could choose from probably 30,000 colors, and have it as flat as you wanted.  Flat does dry much quicker, thus having the effect of both minimizing runs, and much quicker flash times. 

As for different colored primers, SW has a tintable 2k primer for automotive refinishing that can be mixed in 27 different colors.  That look was a trend in hot rod builds some years ago, though I don't know if it still is or not. 

[R.G.]

Why can't they either :
A) Make regular spray paint act like primer
or B) Make primer in a wide assortment of colors
You can spray primer on thicker with less chance of dripping, it's sandable, it dries fast, etc.... When I do white pedals I use white primer with a clear coat over top...it just looks better and goes on with less effort....

Because of chemistry and physics.
The jobs of a primer, in order, are to
1. Bond HARD to the underlying surface.
2. Have a surface that paint bonds to.
3. Everything else.
Primers are colored different colors because:
(a)Different priming situations need different fillers and pigments to further 1 and 2 above and to work with the chemistry that bonds best to the substrate for the first coat. The first coat of primer is almost entirely for job 1.
(b)to have contrasting colors for second through Nth coats of primer. Variegated color primer coats are a GREAT way to tell if you have an auto body sanded to a smooth curve because you'll see color stripes if you eat through the outer ones first.

It's not possible in most cases to optimize the same paint for clinging to the substrate, holding succeeding coats, having a great (and great number of) color, and good finishing. In many cases the chemistry and physics conflict for these jobs. Dumping in other colorants may (or may not, depends on the details) interfere with what the primer's supposed to be doing.

Primers are optimized for fast dry so they can be done quickly and leave a good surface for the color coats.

If you're really into painting like you seem to be, go to Harbor Freight and get yourself two or three of their touch up spray guns. These hold a cup or less of paint, and give you control over paint which moves in the direction of an air brush. More importantly for your question, you can go to one of the two shops in Austin that sell auto body paints and buy whatever top coat color you like. They custom mix for you.

And here's the topper. Get to where you can spray from a pro-style spray rig and you can start spraying Emron or some other catalyzed urethane. You'll need respirators as the vapor is poisonous, not just toxic, but with a paint like that you get water-smooth gloss that's hard enough for boat finishes. Which is where it's used. Catalyzed urethane finishes are so durable that you need to be really sure you like them because they are very, very difficult to remove. 

[darron]

you can also get the polyurethanes designed for spraying aluminium car wheels which is awesone. one or two coats of just one type of spray and you're done!! this only seems to be in metallic colours, black, and clear though ):


added benefit is that it's obviously ultra durable and chip resistant.

[Ice-9]

The way that i usually paint metal items is to give it a coat of etch pimer, this gives it a great key on the metal then a couple of quick coats of a base colour. Base colour although not a primer is a matt colour which is inteneded to have a clear coat put on to give it the gloss, but as its a matt base coat i find it drys quickly, so i can get maybe 2 quick coats on which are thin and don't run. Then lastly i apply a clear coat if i want a gloss finish. You can even put on a semi gloss clear coat.

This is how pearl finishes are done as well. You apply a colour base paint then the pearl coat followed by aclear coat.

But you would need to invest in some kind of spray gun kit.

[R.G.]

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=86
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=46719
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95810

[frank_p]

I wonder what is the quality of the King Canada airbrushes.  I saw this pack for 70.00$ Canadian.
http://www.kingcanada.com/Products.htm?ID=11994
Professional airbrushes are way more pricey than those ones (DeVilbiss are   )
Wonder what are all the differences between the difference in price-quality products.
On professional airguns that they had in guitar making school you could do very "transparent" sunbursts.  Like if the drops of paints were very very small.