Ok, here is a pretty basic question that I'm wrestling with. I'm planning on painting my car myself. I have my test pieces that I'm learning on and I have a "down draft spray booth" in the garage. I'm trying to understand what colorsanding is exactly. Well, check that, I understand what its purpose is but my question is:

Do you sand the actual color layer? After you have laid all the layers or between each one? Or is the clear what you're supposed to be sanding? If it is the clear, how does that remove orange peel or drip marks? If it is the color layer, how do you polish out the sanding scratches before laying the clear?

I'm so confused
Thanks all,
-- Steve

If you are doing a two stage paint job ( color/clear ), there will be no sanding between coats. The clear goes on right over the color after it tacks up.

The sanding, which is #1500 and higher is done just enough to knock down surface imperfections. It makes the paint look free of waves and dust.

The sanding must not go through to the next layer or you will be sad.


I need to do mine still...


KT

Where and when of color sanding depends on the paint.

There are single- and two-stage paints. In single-stage, your color and finish layers are the same paint. In two-stage paint, the color (base) layer is color, and usually does not have a catalyzer mixed in, and the finish layer is clear.

You 'color' sand the last layer of paint.

But, some people are weird and will do both the color and clear coats with single-stage paint.

If you have a two-stage, non-catalyzed base, you don't sand it. Unless you've managed to get a run or drip. But that is a sand and re-shoot operation.

I have done two jobs where the base coat was a single-stage color coat that was sanded. One, I wet sanded that base coat (black) with 1500 grit before applying the clear. The other, the base coat (red) was sanded with with 600 grit or coarser. In the case of the red, the clear coat filled in all the sanding marks.

Me? As a ham-handed klutz, I like the single stage paints. Even though the color isn't as deep, mistakes are much easier to fix. And I make plenty of them.

This is all based on my experience with single and double staged paints, may have that wrong. Anyway.

Single staged paint, paint that doesn't need a clear coat, PPG Delstar. This paint is great, used it on my 6, no clear coat. You color sand after putting all the paint on and letting it dry at least 3-4 days, let dry in sun or heated garage if possible. Start with 600 or 1000 wet/dry, go up to 2000, then start buffing with med to fine to swirl remover then glaze. Then wax. To do it properly, a hood could take 4-6 hours. Use a 6 inch buffer with foam pads. Buy lots of pads, change a lot.

Double staged paint using clear. No need to sand between color coat and clear as long as color coat turns out good. No runs, flies etc. Flies loovvvve wet paint. If you have a run and need to sand color coat, use 400-600 to take run out, lightly rough up rest of panel and shoot clear, the clear will fill in small scratches, you won't see them. If you're gonna color sand clear coat, shoot at least 6 coats, clear is very thin and it's easy to sand through if you don't put enough coat on. So minimun of 6 coats, or what I do. I keep shooting until I run out of clear, once it's mixed with hardener, shoot it or throw it out, might as well shoot it. Let it dry as above and start sanding and buffing. One more thing, it's best to shoot the clear coats right after you finish shooting the color coats, color coats, min of 1 tack coat, 2 color coats, I usually shoot, 1 tack coat, 3 color coats. Well that's it for me.

Later, Don

I do this for a living and can tell you there are cases where you sand the base before you clear. I have a car that will be painted in the spring which will be getting 5 coats of color, wet sanded with 1000 grit, 3 more coats of color wet sanded again with 1200 then cleared in the same manner(multiple coats, wet sanding then more coats). I only will do this on extremely high end cars (which this one is) it is the best way to get an absolutely perfect job. I have already primed and blocked this car 6 times and will block it once more before putting the color on. That said there is no need in 90% of the paint jobs out there to go that far. Once you have your clear on and it has set up at least ovewr night start wet snading with preferably 1200, but if your peel is pretty bad you can use 1000. Go up to at least 1500 before you start buffing and be very careful around the edges. get a minimum of 2, preferably 3 layers of clear on the car, that way you have plenty of paint to werk with.

Edit I said 2-3 coats, that is only if you use Spies Hecker or Glasurit. Any other brand should be 4+ coats. Spies and Glasurit are extremely high solid content hence the price and quality. 2 stage paint is best sanded the day after shooting it, that way the clear is soft enough that it is very easily sanded but set up enough not to pull on you.Waiting more than 3-4 days on 2 stage will make it pretty tough to get out all of the sanding scratches.

QUOTE (scotty b @ Mar 10 2006, 06:56 PM)

I do this for a living and can tell you there are cases where you sand the base before you clear. I have a car that will be painted in the spring which will be getting 5 coats of color, wet sanded with 1000 grit, 3 more coats of color wet sanded again with 1200 then cleared in the same manner(multiple coats, wet sanding then more coats). I only will do this on extremely high end cars (which this one is) it is the best way to get an absolutely perfect job. I have already primed and blocked this car 6 times and will block it once more before putting the color on. That said there is no need in 90% of the paint jobs out there to go that far. Once you have your clear on and it has set up at least ovewr night start wet snading with preferably 1200, but if your peel is pretty bad you can use 1000. Go up to at least 1500 before you start buffing and be very careful around the edges. get a minimum of 2, preferably 3 layers of clear on the car, that way you have plenty of paint to werk with.

Is it possible to color sand the base if the base had metallic flakes? or would that be a bad idea

QUOTE (sj914 @ Mar 11 2006, 02:41 AM)

QUOTE (scotty b @ Mar 10 2006, 06:56 PM) I do this for a living and can tell you there are cases where you sand the base before you clear.  I have a car that will be painted in the spring which will be getting 5 coats of color, wet sanded with 1000 grit, 3 more coats of color wet sanded again with 1200 then cleared in the same manner(multiple coats, wet sanding then more coats). I only will do this on extremely high end cars (which this one is) it is the best way to get an absolutely perfect job. I have already primed and blocked this car 6 times and will block it once more before putting the color on. That said there is no need in 90% of the paint jobs out there to go that far. Once you have your clear on and it has set up at least ovewr night start wet snading with preferably 1200, but if your peel is pretty bad you can use 1000. Go up to at least 1500 before you start buffing and be very careful around the edges. get a minimum of 2, preferably 3 layers of clear on the car, that way you have plenty of paint to werk with. Is it possible to color sand the base if the base had metallic flakes? or would that be a bad idea

NO NO NO. Sorry, I should have mentioned that. Only solid colors can be wet sanded before clearing. Wet sanding a metallic will KILL the job! If you have a run or trash in the base that you need to take care of before clearing, you can wet sand it out and then recoat that area. On solid colors you can get away with a spot repair because the clear will blend it all together, but on a metallic repair you need to blend the repair area into the original area or you will end up with a noticable halo. I'm getting closer and closer to writing a paint article for the site

Scott,
What is your take on clear over a single atage paint ? What are the benefits ? Does it look "deeper" or "richer" than the single stage by itself?
Is it easier than your typical 2 stage base clear paint job ?
Would the clear over single stage work well on a color like silver ?

Scott,
What is your take on clear over a single atage paint ? What are the benefits ? Does it look "deeper" or "richer" than the single stage by itself?
Is it easier than your typical 2 stage base clear paint job ?
Would the clear over single stage work well on a color like silver ?

Personally, I believe that solid colors look better in single stage. There appears to more depth to the paint. Under a clear coat, some colors appear to be of less depth and off color

Tow stage painting with metallics gives you a better opportunity to get an even metallic texture or blending as your color depth is provided by the clear coat. DH

Single stage will get you a deeper look if you want to do a fair amount of wet sanding and buffing. If you build up several coats of clear you can get a similar depth. IMHO I don't care for single stage because the little I have done with it, I found it to be very bad as far as chip resistant. I have only done 3 single stage jobs but every one ended up with a rock chip or two that was HUGE. Single stage seems to setup a lot harder and doesn't give much when a rock hits it. May have been the type of paint I used or maybe I just didn't set it up correctly. I thought at one time it would be cool to be the " single stage guy" in town because few people do it. Now I know why. It just isn't as practical in most cases.

As for single stage metallics, I wouldn't do it for one simple reason. As stated before you can't wet sand a metallic. If you do, you flatten the metallic and lose the effect, therefore a single stage metallic must go on perfectly.

If you want to do a single stage solid color, build up several layers of paint in order to wet sand to a nice smooth finish then buff and hand rub the crap out of it and you will get a deeper look, but you'll be worn ass out Just remember either way to step up the grade of your sand paper each time to eliminate the previous sanding scratches, and start with as high a grit as you can.Try 1500 first and if it just won't cut through step down to 1200 then 1000 but I would really advise not going any lower than that. If you need to plan on re shooting the clear and base if you have shot metallic

Painting isn't rocket science but it does take some knowledge, patience and elbow grease