Paint gurus...

[Dirk Diggler]

I had one thread asking why my clear coat bubbled after repaint. Got that all figured out and painted a fender. I need some advice on what to do from someone who does paint...

 

I used a grinder and a sanding disk to go down to bare metal. The sanding dish left small valleys in the metal that I couldnt see until I sanded my first coat of color. Whats the easiest way to fix this? They are everywhere on the fender, and look like little door dings. I tried taking a picture but couldnt get them to show up. I can take a picture of the fender sanded down tomorrow at some point. All I can think of is spray a bunch of coats, then sand it down to make it level, but im not a paint guy. Any ideas?

 

 

[izzo]

not a paint guru either, but i would sand it back down to bare metal and use some filler!

[Laecaon]

Im no pro but I think it might depend on how shallow these valleys are. If fairly shallow sand the mountains down and see how far this gets you, obviously you dont want to see primer, but if you do it simply means another coat of paint or 2. If fairly deep, it might be better to just strip with aircraft paint remover (autoparts store). Use some body filler, then redo it all. Im sure 510keeper will be here soon enough though.

[Dirk Diggler]

There are no mountains, just valleys. It seems like the grinder took out some metal once it got through the paint in some areas. I dont want to use body filler on the entire fender, that is over kill. If that is my only choice, I will just get a fender from a junk yard. Im thinking that spraying about 10 coats of paint will fill in the valleys so that I can sand down the fender and have it all smooth.

[steve g]

There are no mountains, just valleys. It seems like the grinder took out some metal once it got through the paint in some areas. I dont want to use body filler on the entire fender, that is over kill. If that is my only choice, I will just get a fender from a junk yard. Im thinking that spraying about 10 coats of paint will fill in the valleys so that I can sand down the fender and have it all smooth.

Take it back down to bare metal... load up with urethane primer and block it down flat.

[RedSquare]

There are no mountains, just valleys. It seems like the grinder took out some metal once it got through the paint in some areas. I dont want to use body filler on the entire fender, that is over kill. If that is my only choice, I will just get a fender from a junk yard. Im thinking that spraying about 10 coats of paint will fill in the valleys so that I can sand down the fender and have it all smooth.

 

I'm no paint guru or anything, but don't use a grinder to remove paint. BTW most/all professional paint jobs use some sort of filler/glaze to get the panels straight. You really sound like you haven't researched how to paint a car before you dived in. "10 coats of paint to fill in the valley"?? That's your glaze and or primers job.

[jun]

A few coats of polyester primer will fill in deep gouges and marks from sanding discs. It's basically liquid bondo shot out of a spray gun. Guide coat it, block it flat, most of the primer will be sanded off but it will leave you with a smooth, straight panel ready for paint if you do it right (and your panel isn't too trashed to begin with)

[Laecaon]

There are no mountains, just valleys. It seems like the grinder took out some metal once it got through the paint in some areas. I dont want to use body filler on the entire fender, that is over kill. If that is my only choice, I will just get a fender from a junk yard. Im thinking that spraying about 10 coats of paint will fill in the valleys so that I can sand down the fender and have it all smooth.

By mountain I meant not valley. Basically High spots.

[Dirk Diggler]

Take it back down to bare metal... load up with urethane primer and block it down flat.

Thats my other idea, just using primer instead of paint.

 

I'm no paint guru or anything, but don't use a grinder to remove paint. BTW most/all professional paint jobs use some sort of filler/glaze to get the panels straight. You really sound like you haven't researched how to paint a car before you dived in. "10 coats of paint to fill in the valley"?? That's your glaze and or primers job.

I was told to use a grinder with sanding disks to get to bare metal. I accidently got too course of disks, thats why it gouged the metal. I did some research, but im not a body guy, and im not a paint guy. I have never done any body or paint work in my life before this, so obviously there will be some trial and error. I dont claim to know what im doing, thats why I came here for help. Im not trying to get a show quality paint job, hell im using rattle cans. I only want to get rid of the brown because it looks like shit, literally. And 10 coats of paint, loading it up with glaze/primer, whats the difference? Its still getting filled...

 

By mountain I meant not valley. Basically High spots.

I know, I dont have any high spots. They are all low spots. Its pretty much like there are a shit load of dings in the fender, but they arent actually dings, just missing metal.

 

 

Skib has a set of fiberglass fenders for sale, maybe this is a sign I need to pick those up :)

[DanielC]

Use the primer surfacer on it. Then sand it, using a guide coat. You want to use a long board to sand down the guide coat. Use long strokes to sand, with light pressure. Do not just sand in one direction.

[steve g]

I didnt know you were using spraycans.... at this point i will assume this is a very budget based paintjob....

Dont bother even trying to cover the marks with the paint, spraycan paint has no fill at all and you will prpbably have a wet-on-reaction (wrinkling, lifting) long before you have any success.

But while keeping "budget" in mind the urethane primers are out.... Polyester primer like the other guy suggested should be better for you.. far cheaper and has extreme fill, you will need a large tip spray gun because the stuff is thick. If for whatever reason you need or prefer to stick with spraycans then try using SEM high build primer surfacer in a spraycan. Good stuff and will fill up to 120 grit scratches and has minimal shrinkdown, easy to sand wet or dry.

[Dirk Diggler]

This is pretty much a no budget paint job. I am using auto primer and Rustoleum auto paint, but rattle cans are rattle cans. I would be using a gun, I just don't have the space right now. I'll give the SEM stuff a try, thanks for the tips

[jun]

Dirk.

If you have a lot of filling to do, spray cans won't do much. Don't have access to a gun? You can apply Polyprimer with a cheap paintbrush, or even a roller. Hell I've done it when I had to do a spot repair, and didn't want to dirty up my spray guns. Make sure you add the hardener to it (clear MEKP) or it will never dry. It will be a lot harder to sand the texture out but it will build high and fast. A quart of cheaper brand polyprimer (like PCL) will cost you about $15 at most, and it will go a long way. Lay it on over the trouble spots with a brush, give it a few good coats. It will be rock hard in about 30 min, depending on the temps and how much hardener you add. knock the texture down with a block and 180 or 220 grit, spray a guide coat, block again with 320/400 and if you did a good job, you would have saved a good amount of time and money and have a smooth panel to paint. You could even take it down to 600 grit if you want an even nicer finish to paint over.

 

I will also vouch for the SEM product line. Their high build primer works pretty good but I have a feeling that you need more fill than what the spraycan primers can do.

 

Either way, SEM and PCL products are a more commercial grade material compared to Rustoleum. Have good ventilation and a proper respirator if you're using that stuff.

 

One more thing. Don't expect any "fill" from paint. It has no filling qualities, not to mention you'll waste a good amount of money. If you're trying to hide something with 10 coats of paint, you'd be better off with a few coats of primer, a light skim coat of filler, some careful block sanding, and 2-3 coats of paint. Once the solvents dry in paint, all you're left with is a very thin film that won't hide anything...actually it will just amplify your surface imperfections.