clear coat flaking off roof edge panels

[katoomer]

A couple months ago I noticed the clear coat peeling or flaking off in a half dozen or so spots on the radiused roof edge panels on our coach. Always in the middle of the panel, never near the edge and only on a horizontal area not vertical. I can actually peel it off with my fingernail. Coach has been winter stored under cover for the first 4 yrs. and had a cover for the last 2 winters. Always kept clean and waxed twice a year. Local body shop that I trust
says it it caused by poor adhesion when originally painted. If it was from cover rubbing on the paint I should not be able to scratch it off with my fingernail so please don't suggest that. I also noticed a soft spot in the middle of one panel in the fibreglass to the point that I could poke a hole in it with my finger if I pushed hard enough (poor fibreglass work). I'm hoping to do a bit of touch up with spray clear in affected areas only with the hope of stopping any further progression. Has anyone else had this problem with their Newmars?
Lucky for Newmar it didn't appear until long after my warranty expired (not lucky for me).

[Tom_Barb]

s N s wrote:


When you use the term polishing compound, are you talking about rubbing compound or some other type of product.

I use THIS

[katoomer]

LOL Don't be afraid to use sandpaper. Just use a very find grit #1500 or finer. Wet sanding is even better. Lightly sand, and pay attention. Rubbing compound will not remove any of the clear coat, unless you are using a buffer. Do it by hand. Ask a bodyman.

[s_N_s]

rgatijnet1 wrote:
Polishing compound is a much finer grit than rubbing compound. It will remove a lot less material and leave the surface ready for wax.
If you use rubbing compound, you need to use polishing compound afterwards.

Thanks for the info.

[rgatijnet1]

Polishing compound is a much finer grit than rubbing compound. It will remove a lot less material and leave the surface ready for wax.
If you use rubbing compound, you need to use polishing compound afterwards.

[s_N_s]

Tom/Barb wrote:
I would avoid using scrappers and sand paper. they are too easy to make scratches that will show after buffing. Clear coat is really thin, and the edges will be hidden when you buff with polishing compound.

When you use the term polishing compound, are you talking about rubbing compound or some other type of product.

[rgatijnet1]

imgoin4it wrote:
When i tried a repair I attempted to feather the egde of the clear coat with fine sand paper. The color coat was so thin when it was "touched" it was gone. Clear coat cannot be cut in or patched but I figured at the top and roof of the coach it would not be noticeable. Not sure about other products, but if you have this condition on a Newmar motor home I think you will need a professional fix.

You are correct. If the paint is so thin on the Newmar coach that to touch it removes the color coat than polishing compound will certainly remove the color coat of paint. If the factory put it on that thin, just rubbing it to put on wax may remove what little is left in which case a repaint is the best solution.

[Tom_Barb]

I would avoid using scrappers and sand paper. they are too easy to make scratches that will show after buffing. Clear coat is really thin, and the edges will be hidden when you buff with polishing compound.

[Tom_Barb]

s N s wrote:
Guys, what's the best way to remove the clear coat? On ours we have sections where it is peeling and then sections that are still OK. If possible I would like to remove it all and just buff and polish it if that's possible. Thanks.

If it is not loose, it does not need to be removed, I used a pressure washer to blow off the loose portion, and then buffed the area.

You really don't have to get very close with the pressure washer to get under the loose clear coat and take it away.

[katoomer]

s N s wrote:
Guys, what's the best way to remove the clear coat? On ours we have sections where it is peeling and then sections that are still OK. If possible I would like to remove it all and just buff and polish it if that's possible. Thanks.

I would recommend not removing it all. Just the areas that are peeling. Use a 1500 or finer grit open coat sand paper and remove the peeling sections. Be careful not to sand thru the
color coat. Then polish and apply a quality wax.

[imgoin4it]

When i tried a repair I attempted to feather the egde of the clear coat with fine sand paper. The color coat was so thin when it was "touched" it was gone. Clear coat cannot be cut in or patched but I figured at the top and roof of the coach it would not be noticeable. Not sure about other products, but if you have this condition on a Newmar motor home I think you will need a professional fix.

[rgatijnet1]

The clear coat that is peeling can be scraped off and then you can feather the edges with fine wet/dry sandpaper to blend everything smooth. The problem is that you don't know when or if the rest of it will start peeling in a week, month, or never. Once the loose clear is removed, you can try using a polishing(not rubbing) compound followed by a good wax. This may bring back some of the gloss to the surface.

[s_N_s]

Guys, what's the best way to remove the clear coat? On ours we have sections where it is peeling and then sections that are still OK. If possible I would like to remove it all and just buff and polish it if that's possible. Thanks.

[Tom_Barb]

rgatijnet1 wrote:
Perhaps you should tell hi about your refinish system and how it can help his problem.

Already did.. his best and cheapest is to simply remove the loose clear coat, buff and wax.

Our coach was a different problem. We replaced a basement door, and refinished the lower rear cap, due to rock chips and a mower incident. :(. I simply hand sanded filled the chips and recoated with S-W two stage. that will last as long as we own the coach.

[rgatijnet1]

Tom/Barb wrote:
The STCs for upgrading the fabric to Ceoconite requires the system to be applied as per the installation instructions which have the materials listed. They do not include a three stage automotive paints. And that is what Clear coat systems are (three stage). the all aluminum aircraft can use any system they like, but adding the third coat of clear coat is heavy. most do not use it.

I have refinished our Newmar in several places, the company gave the paint info as a Sherman Williams numbers and we used S&W two stage no clear coat. It looks better and will last as long as any three stage.

Most automotive base coat clear coat systems are two stage now. Since you do airplanes here is a modern system using base coat/clear coat that will not add the weight that you are concerned about. Aviation paint
Apparently the Newmar that the owner has was coated with a base coat/clear coat finish that has failed. Perhaps you should tell hi about your refinish system and how it can help his problem.