Touchup paint: large area

[supton]

On my truck there is a spot on the door sill where the previous owner must have sanded down... with their pant leg... something fierce. I'd say it's a quarter inch tall, by 18 inches long, of paint removal. It's on the door sill, where the metal goes from horizontal to vertical.

The metal is still very shiny, even after sitting for four months in my yard. The area is very well protected by the door, the area is inside the door seal so I don't think it will ever see water. Except for what is tracked in by me, in winter. I have to wonder if there is a thick layer of zinc/some sort of metal protection layer here.

Rather than mask off the entire door area so as to avoid keeping primer outside of the car, I'm wondering if I can expect reasonable adhesion with the touchup paint? Even if I kill a bottle (at $9 a pop) it's still cheaper than primer and then whatever it'd cost for a matching spray can. I don't care about having to touch it up every so often, since I have to do that anyhow on the hood. The metal is smooth but not perfectly so, not sure exactly what they dragged across this surface.

 

[Mr_Incredible]

My '99 F250SD is a rust bucket. I have a very active rust abatement program going.

I found the most effective treatment over the longer term is to blast areas, prime, paintd, and clearcoat. Sanding will work but doesn't get down to the rust you can't see. It WILL come back. I use the paint-match spray cans from the parts store and a quality automotive primer in a rattle can.

No rust? Probably doesn't matter what you use. Scuff with at scotchbrite pad, prime, paint, clearcoat.

 

[gofast182]

If no rust or even light surface rust, just do what Mr. Incredible said. Only thing I'll add is make sure you mask off a very large area, maybe even the whole side of the vehicle as you will get overspray over a much wider area than you might expect.

 

[SatinSilver]

Yep, Duplicolor sells small cans of spray paint for the same price as touch up paint. At Autozone etc... At a minimum wipe the area down with rubbing alcohol and mask off the surrounding areas with newspaper.

 

[doitmyself]

To the OP, color coat only does not have the bare metal adhesion that primer does and will probably peel off.

 

[Astro14]

I would sand, degrease, prime then spray...you can get a 12 oz rattle can in your color for $20. It will do more than you needed, and the coat will be reasonably smooth...touch up bottle will be lumpy and obvious....

 

[supton]

If touchup paint lacks primer, why is used? Just hopeful that it will catch enough of the remaining paint, and be small enough, to do the job?

I suppose the color doesn't have to match, right not it certainly doesn't.

 

[zzyzzx]

We need pictures to better assess the situation.

 

[doitmyself]

Originally Posted By: supton
If touchup paint lacks primer, why is used? Just hopeful that it will catch enough of the remaining paint, and be small enough, to do the job?

I suppose the color doesn't have to match, right not it certainly doesn't.


Touch up paint is the same as the spray paint. It's just a different non aerosol container with a brush. Maybe the aerosol is thinned more...maybe.

I use primer with the brush type touch up too, even tiny rock chips. Clean, roughen/smooth, primer, then top coat is the standard procedure. Touch up paint used alone on a tiny rock chip will often pop off also (without primer).

Buy the aerosol. If you want to use it as a touch up with a toothpick or tiny brush, spray some into a bottle cap. The same thing with a spray can of primer. You can get two small cans of Duplicolor primer and color coat for well under $20.

Shake the cans well. When done,turn upside down and spray until clear to keep the nozzle unplugged.

 

[supton]

Originally Posted By: zzyzzx
We need pictures to better assess the situation.


Let's see if I can post a pic:

Nope, still haven't figured out how to embed photos, sorry.

 

[supton]

Lousy pic, but truck is at home and I am not.

 

[doitmyself]

I I am interpreting that photo correct, that doesn't seem like it was caused from a dragging pants cuff. Considering the discoloration of the paint surrounding exposed metal, is there a chunk (or used to be) of weatherstripping hanging loose from the bottom of the door. Some truck doors have an additional rain/mud weatherstrip attached to the door bottom. Look at the other door to see how it is made.

I still would use the recommendations above to repair it.

 

[dave123]

Originally Posted By: doitmyself
Originally Posted By: supton
If touchup paint lacks primer, why is used? Just hopeful that it will catch enough of the remaining paint, and be small enough, to do the job?

I suppose the color doesn't have to match, right not it certainly doesn't.


Touch up paint is the same as the spray paint. It's just a different non aerosol container with a brush. Maybe the aerosol is thinned more...maybe.

I use primer with the brush type touch up too, even tiny rock chips. Clean, roughen/smooth, primer, then top coat is the standard procedure. Touch up paint used alone on a tiny rock chip will often pop off also (without primer).

Buy the aerosol. If you want to use it as a touch up with a toothpick or tiny brush, spray some into a bottle cap. The same thing with a spray can of primer. You can get two small cans of Duplicolor primer and color coat for well under $20.

Shake the cans well. When done,turn upside down and spray until clear to keep the nozzle unplugged.


Most paints for spray cans are cut 50to100% or more with solvent prior to packaging.

 

[supton]

You're right, there is weatherstripping in that area. But it looks properly secured.