"Fixing a Run or Sag in your Clear Coat"

How to fix a run or sag in your clear coat.

By Don Johnson
airbrushgallery.com
www.airbrushtechniquemagazine.com

Yes it happens to everyone from time to time a sag or run when applying clear coat. Even the best of the best have an off day once in a while, after all what is custom painting if not an exercise in solving problems. And a sag or a run is nothing more than that another little problem to be solved along the way.

Below is just one way to handle the problem of a run or sag in your clear coat. What you'll need: wooden paint stir stick, wet dry sand paper (depending on what stage of the project you are on 800 grit to 2000 grit), bucket of water and of course a sag or run in some clear.

This little technique will work as well with a well cured spray bomb clear (like U-Poly) as a two part automotive clear.

Pictured above: There you have it the dreaded sag or run in the clear coat. And yes thats my handy work who else would be crazy enough to post on the Internet a mistake they made in a customers helmet than a person whose company name contains the word airhead.

Pictured above: Our bucket of water and wooden paint stir stick. When using wet / dry sand paper be sure to let the paper soak for 10 minutes or so. Taken right out of the package and used even wet the sand paper might will scratch the surface rather than sand the surface. Always let the paper soak for ten minutes to allow the paper to soften before using it.

Pictured above: Cut an inch or two off the wooden paint stir stick which you will use to wrap the softened sand paper around.

Why use a stick? If you where to just use the sand paper lets say you would find it very hard to ever sand that sag or run out with out effecting the surrounding surface. The goal is to just sand the high spot ( the sag or run) and using the hard flat surface (the wooden stir stick) allows you to do just that with out effecting the area around the sag.

Which grit sand paper to use? Depends on if this is the final clear coat to be buffed or just a protective clear over some art work and more art work is to be added.

Pictured above: With your sand paper stick you want to sand going across the sag or run. Provided there is no solvent pop in the run or sag this should cut the run, sag down in no time. Be sure you have given the clear enough time to cure 100% before attempting this. Start out with a courser grit sand paper and use a finer grit sand paper as the run, sag gets down closer to the surrounding area. Keep the paper wet at all times during this. Sand with the stick flat against the surface.

Pictured above: As you can see my run, sag has pretty well disappeared, at this point you might want to start using a very fine grit sand paper. If its a final clear you might want to be using 2000 or 2500 grit at this point. Be careful not to go to far and flat spot that area or worse sand down thru the clear.

Pictured above: There you have it no more sag or run ready to be buffed or with the rest of the surface scuffed ready for more art work.

There are other ways to handle this problem but this is one I have found easy to use. Hope you find this helpful, keep spraying and have fun, until next time.