Paint problems in very high temps this summer

[Gary.Jones]

I have a buddy that sometimes haunts this forum but doesnt often post threads and he has asked me my opinion on a matter that is bothering him. He has been spending a lot of time in Texas this summer and Texas temps have often been in the mid 100s (e.g. 105 +/-) and he asked my opinion on whether these high temps, and even higher temps when coach is parked in direct sunlight, represented any serious potential problem for his paint on his 2015 Anthem.

Now, I am no paint expert. I reminded him that over his paint that he has a large number of clearcoat layers that protect the paint, and clearcoat is well known to scratch and mark anytime it comes in contact with branches or debris, but I have parked my 15 Anthem and now 19 Cornerstone in the same temps in my driveway since 2015 and have never had a problem with the paint on the coach.

Now, I told him I would publish his question and summarize the answers from people more familiar with any risks to the exterior paint than I am. What say you paint experts?

Gary

[brobox]

A good coat of any quality paint protection becomes very important. i have switched from wax to polymer. If clear coat is not protected it will start to blister or peel.

[sibe]

I can write a book on paint, been painting in auto industry since 16, 61.5 now..

I have had Clear coats fail requardless of care and others look like new after 25 years in the weather with almost zero care..

RVs have some inherent issues with certain coatings.. Fiberglass has gelcoat surface that gets painted or some are colored in gelcoat.. The Fiberglass moves and is under UV attack.. Good paint will expand xcontract well and have lots of UV protecter in clear..

SMC, mistaken for fiberglass, is used,, sheet molded composite.. This is used on caps and other places.. Pretty stable..

filon type laminates.. works well. takes paint and vinyl raps

RV's are not really production painted as autos at factory.. auto paint is a huge science and has become very good and durable.. once in a while certain models peel, .. happens when process changes or suppler mismatch.. whatever, it happens..

RV's are more so hand painted with what I call aftermarket paint systems.. hence the custom look and nice shine on many..

I would say that most major RV companies use better main stream paint , these paints are very very good. Most require minimal care..
MOST IMPORTANT is The Coatings used on RV;s is like I say not a super high temp baked . thermo set paint.. It is a catalyzed product that is air dried or low baked at 140-160.. Some new UV cured is for small parts in some industrys..
Anyway, It has to fully cure even after a bake cycle , it can take weeks for all solvents to escape,, SO SO NOT WAX, SEAL etc until it is a couple months past manufacture..

There are some good high end expensive polymer,, special sealants, most need a yearly , clean and touch up reseal.. They help, some add a tad of UV reflection, other do not..
I am trained.certified in 2 brands.. both have maintenance sprays or plans..
my shop has downsized and I can make more money other ways..
we do a few vehicles for good customer. They all like it.. so do I.

Try to keep RV clean, use a truck wash place and even the spray waxes help .. road film and tree grime will degrade paint..

AS for the heat question.. and humid weather.. Humidity would maybe hurt OLD paint finished of the 60;s, 70's.. lacquers non catylized enamel etc..
Humidity today, helps the catylast in urethanes cure out.. I can paint in 95 degrees 90% humidity all day and actually get my best work..

A closed up RV dark colored in desert 117 close to sun, will bake, possiblly show sun damage faster than my climate in PA, but we have 50-60 temp swings in a few hours.. that is not good either,,

SO IMO , clean, wax it, sure shade is better for any paint.. but enjoy it..

My 96 is not a shiney puppy, it takes a yearly sealant wax, then a fast spray seal before winter. last 4 years I own it.. no cracks , no peel other than some decals..

[zman62]

I live in AZ. If a coach is in direct sunlight I don't care what you put on it the clear coat will fail

[bpu699]

Take a laser temp gun, and check your paint temp… you would be suprised.

On an 85 degree day, my white fiberglass rv shows 105 degrees.

I can only imagine the paint temp of a dark color, on a really hot day…

[brobox]

sibe, that was an excellent read, thank you.

[Turbojack]

Originally Posted by bpu699

Take a laser temp gun, and check your paint temp… you would be suprised.

On an 85 degree day, my white fiberglass rv shows 105 degrees.

I can only imagine the paint temp of a dark color, on a really hot day…

135-155

[LVUS101]

Thanks for posting this Gary. Good information by quite a few people

[buddy110]

Originally Posted by brobox

A good coat of any quality paint protection becomes very important. i have switched from wax to polymer. If clear coat is not protected it will start to blister or peel.

I loved my polymer finishes. They last ~6 months and shine like nobody's business. I was a big Zaino fan. Apply, let dry, buff off. It leaves no waxy residue. I haven't used wax in decades. I have since moved to ceramic coatings. Both however, require a proper paint correction prior to application. Since both are near "optically perfect" they will amplify the imperfections in your paint.

Originally Posted by zman62

I live in AZ. If a coach is in direct sunlight I don't care what you put on it the clear coat will fail

Absolutely.