Duplicating primer showing through the paint

[junkyardjeff]

I am going to build a 40 ford sedan delivery that I want to have old looking paint with primer showing through the high wear areas and wondering on the best way to do it.

[Ace-Garageguy]

Best way to do it is to really do it. Primer your model the color you want as primer to show through. Then paint it whatever "worn" color you want.

Then simply sand through the color coat to expose the primer in the appropriate areas.

You need to use really fine paper...wet-or-dry paper, used wet...so you get a very fine and subtle feather-edge transition between your topcoat and primer show-through areas.

PRACTICE / EXPERIMENT FIRST.

[junkyardjeff]

And after thats done would should I clear it.

[Ace-Garageguy]

  On 7/10/2016 at 2:45 AM, junkyardjeff said:

And after thats done would should I clear it.

Probably not, but it's going to depend on the exact look you want.

There's a trend in 1:1 patina'd cars now to shoot clear over rust and faded /weathered paint and primer, but I think it looks goofy.  

I've only done a couple, but sanded-through paint looks exactly like paint that's worn off to primer...'cause it is.

There are several guys on here who do a lot of it and do it really well. They can tell you more, like if you want rust showing through your primer in spots as well...which is beyond my current pay grade.

 

Edited July 10, 2016 by Ace-Garageguy

[Jantrix]

  On 7/10/2016 at 2:38 AM, Ace-Garageguy said:

Best way to do it is to really do it. Primer your model the color you want as primer to show through. Then paint it whatever "worn" color you want.

Then simply sand through the color coat to expose the primer in the appropriate areas.

 

Also if primer is wearing through it's because the paint has been worn thin, so your top color should be a very light coat.

  On 7/10/2016 at 2:45 AM, junkyardjeff said:

And after thats done would should I clear it.

A coat of dull clear will help give you consistent finish, that is, one area won't be shinier than the rest because you didn't want to sand a particular area very much. It will also keep decals from looking too shiny on your weathered model, should you choose to use them.

[junkyardjeff]

I have never done any weathered builds so I need all the help I can get,I also want to go with the faded paint look too. I do not want it to shine at all if possible.

[Ace-Garageguy]

If you have a shiny model you want to make look dull, all you need to do is to scrub it with a toothbrush and something like old-fashioned Comet or another abrasive cleanser. Besides being excellent for prepping bare plastic for good primer adhesion, it also works beautifully for removing gloss to get a weathered effect.

To me, shooting a coat of flat or dull clear over everything looks fake, as it evens the surface out too much.

Again, this is an area where YOU need to experiment with various techniques to get an effect that looks real to you. 

[Snake45]

Are you using an airbrush? The effect you want should be rather easily accomplished with a good airbrush.

It's going to be a bit harder with rattlecan and sandpaper, but it is do-able.

[Ace-Garageguy]

It's not hard at all to get a primer-show-through effect with sandpaper. This is the only one of mine I could find any online pix of, and I'm too lazy this AM to go looking on my own hard drive, but you get the idea.

This was a completed shiny AMT '32 body shell of someone's I got with a bunch of parts. Several areas have been sanded through to various depths to give it a worn-paint effect, with the decklid area being the best example of the look I think you're after.

The shell was also scrubbed with Comet first to break the gloss.

Edited July 10, 2016 by Ace-Garageguy

[Tom Geiger]

First, I will say that you need to practice on scrap bodies before working on a model that matters. Weathering is an art, and there are many techniques and materials.  You do not need an airbrush, I do all my work with rattle cans and by hand.  Most of the effects I create are akin to water color painting.

Second, RESEARCH... note in all capitals! It's easy today to find photos of worn vehicles.  eBay Motors is my first go to place. Then examine your photos. You will notice that vehicles weather to their environment.  Simply put, West Coast cars wear from the top down due to the beating sun and dry climate.  East Coast cars wear from the bottom up, due to salty roads in winter.  All in all a vehicle will have varied tones so you don't want to just hit the whole thing with Dullcote.  We are not addressing dents or rust through.  I will say that you want to look at the rust patterns on a specific vehicle.  For instance, Tri-Five Chevys rust above the headlight.  Mid 60s Valiants rusted on the fender tops.  There are typical areas like around the rear wheels, the quarter panel behind the rear wheels etc, too.  But again, be sure. For instance a 1962 Studebaker Lark won't rust in the quarters, those are removable and are a metal that doesn't really rust!

To establish your base, I would do several coats of paint.  First coat - red primer  Second coat - gray primer  Third coat - paint one body part a color other than your final color for interest Fourth coat - your color coat.    You don't need to do any of these light or heavy.  The crummier the job, the better it will be as a base.  I recommend wet sanding, as Bill said, with a fine grit sandpaper.  I do this at the sink.  Do your sanding in small circles, one problem I see on a lot of models is where people sand front to back in strokes. No car weathers that way. So start in an area where you want to see through the paint.  Do this slowly and watch your result.  Keep washing the part under the faucet to see your progress.  You want the pattern to emerge and show through one or two of the coats. Your high points will appear.  If you go through to plastic color, stop!  But no worries.  That's where I will add a dab of rust with chalks. If indeed you did the different color on one fender, like a red fender under your final blue or green paint job,  that red will also emerge in your sanding. You will want areas where the final color is gone but red shows. That adds interest to the model as a fender that had been replaced many years ago.  Note that your final product will look much different dry than what you see wet as you sand.  You don't have to do it all at once.  Go so far,  dry the body and see what you've got.  You can always sand more later.

Here's a few photos-  

The truck is actually dark green like the above photo.  The below photos came out very light, probably the camera getting fooled by the dark background.  But these lighter photos do illustrate the work decently.

Here's some high point sanding.  Paints here were nothing more than Testors gray primer and some hardware store Christmas green paint I had on hand. The roof has a dent in the center so you can see the outline of that dent and the rust from sitting water in the center. On the hood you can see how the primer below emerges with the circular motions.

See where the sides have more green paint than the upper surfaces since they would receive less sun.  You can do some mist coats of Dullcote and semi gloss. I've angled the model body and shot semi gloss from the bottom edge upward.  If it mists and speckles, that can add to the effect.  You can always sand the edges of this work down a bit for realism too.

 People have criticized that the sign isn't weathered enough, but it was not supposed to be.  That's a sign mounted on the truck recently to advertise Christmas trees. I did bleed the nail holes as if the nails have rusted as if they were exposed for a season or two. This model was built in the early 1980s and that sign was drawn on CAD back then.

See that the firewall is closer to the original green since it would have zero sun exposure. It would still be dirty.

Add interesting features like a brand new battery and cables.

and notice the darker gray highlights.  Those were done after the initial sanding.  Dark gray brushed on and then wet sanded off to eliminate any edges.  Mostly I can say work slow and constantly review what you've got.  Done right you will have a stunning model. And as with everything else, you will improve with practice.  Good luck!

[junkyardjeff]

Time to find some junk bodies to practice on,I was wanting a dull paint with primer showing through in some areas. I was not wanting to get into rust or rusted out areas just yet but will eventually.

[Skip]

Two ways I've used to produce Faux-Tina primer showing through the topcoat are both done with airbrush for academic and a detail gun for full size.

1.  Prime + Topcoat, try to apply the topcoat thinner in the areas you intend to burn through later.  Next use either a polishing pad running up and to toe finest grits burning through to the primer where you want the primer showing.

2.  Prime + Topcoat + Primer in the areas you want it to show.  Use either a Polishing Compound or Polishing Pads to burn back the primer to thin coated areas over the topcoat where it would normally burn through with age.  Again progress through the finer grits of polishing pads (skip the rough stuff) you want to polish to the primer if the effect you are going for is paint that has been waxed and polished so much that it has thinned and the primer is showing through the topcoat.  This applies to both techniques.

The final step would be to use a past wax to wax over the whole area that you've thinned.  This will protect the effect and keep the paint and primer from oxidizing to the point you may have t o polish it again.  Don't go all crazy and make the thinned paint so shiny that it's not believable to the eye, you're trying to trick the eye into recognizing worn paint.  Observe real worn paint and try to duplicate the areas that normally wear thin with age, crowned areas, sharp transitions and creases.  If you've ever burned through the paint when you were trying to polish, you've already got some experience with this technique!