Page 1 of 2
Automotive clear coat over CPES?

Posted:
Sat Oct 21, 2006 9:58 pm
by jmtk
I sealed up my trailer today with CPES cold weather formula (only got up to 47 for the high). Now I'm trying to decide what to put over the top of it for UV protection. I've read that automotive clear coat is low maintenance compared to varnish. Low maintenance is good. My trailer will be stored outside, so I need something highly durable, although I'll probably have a cover made for it. Now for the questions:
Can you get a decent finish by using a brush to spread the clear coat? I've never used a sprayer nor do I have one. I'm not Doug, so am not looking for a mirror finish, just something that looks nice and holds up well.
Would I need more than one layer for good UV protection?
I don't think we'll be seeing temps above 50 again till spring. Can it be applied in cool weather?
Any particular brands that people like?
Thanks,
Jeanette
And of course, here's the requisite picture:


Posted:
Sat Oct 21, 2006 10:53 pm
by Juneaudave
I suggest Sikkens Auto Clear...good UV..and some of my kayak and canoe friends are using it. Check out this site...
Sikkens example ...This is best shot in a booth, and it is a two part clear, but I hope that gives you a thread to chase...

Posted:
Sat Oct 21, 2006 11:05 pm
by Leon
Automotive cloear coat may or may not be a good coating for your application. I've seen clear from one brand put over an automotive base coat of a different brand fail over time. A clear coat on a properly applied automotive finish must be applied over the base coat within 24 hours (and some manufacturers state within 12 hours) as the clear forms a chemical bond with the base. If it is applied after that time you have to sand the base coat, reshoot a coat , then topcoat with the clear. It may work, but I wouldn't bet money on it. Look at how many early 90's cars has the color coat falling off the primer - paint formulations were changing and the manufacturers didn't know the long term effects of the new stuff. When they got everything to work together, it held up but not until then. I'd go with the approved brand and type paint they recommend to put on top. If they don't have something that they garauntee will work - well then it's a chance you'll take. Also, don't brush automotive clears. If put on too thick they will fail. The most common is checking or crazing.

Posted:
Sat Oct 21, 2006 11:16 pm
by jmtk
Juneaudave wrote:...This is best shot in a booth
Pardon my ignorance, does this mean done professionally?
From what Leon is saying, sounds like I wouldn't be applying it in time since I wouldn't be able to get any by tomorrow
Maybe it'll have to be some spar varnish...
Jeanette

Posted:
Sat Oct 21, 2006 11:23 pm
by madjack
Jeanette, Doug probably has the most experience with the clear...unfortunately he is out of town/pocket until???? I don't really know enough to offer any advice except to say...spray it...even a cheapie airless/electric is gonna do a better job than brushing
madjack


Posted:
Sat Oct 21, 2006 11:57 pm
by Juneaudave
Gosh...I surely didn't mean to imply that Sikkens Auto Clear was the product...I only wanted to give you a start. At 50 degrees max daytime temps, spar varnish will take some time to dry, and weeks for it to really get hard, especially with multiple coats. Spar is great for brush work. If you go with spar varnish, my recommendation would be to look for a dry and dust-free place to get the results that I think you might want.
I've really come around to liking the automotive clear coats in the past several years and I think that they are a good choice if you can spray them. The one question you have to ask is....What is the difference in cost from having a body shop shoot on a couple layers of clear verses the cost of applying a good spar? By the time you invest in wet/dry sandpapar, a couple quarts of good spar (Captains, Schooner, etc), thinner, cheeze cloth, brushes, tack cloths, your time....I'm not so sure varnish is the bargain it may seem.
So..still no definitive answers I guess...
For giggles...it may be worth taking a pic of the tear to a couple of body shops and see what the cost may be. I know the board would be interested in what you find out....Juneaudave

Posted:
Sun Oct 22, 2006 1:08 am
by asianflava
A spar urethane would also give you good protection. It is still better than varnish but not as good as catalyzed clear coat. It's probably more labor intensive to apply but it is more forgiving. You can either brush or spray it on, the more coats the better.
I'm not shure how much maintenance is involved with it, but it is recommended for use on outdoor furniture. I used it on the interior and the galley cabinets.

Posted:
Sun Oct 22, 2006 7:09 am
by Arne
Can spar urethane be sprayed out of a cheap harbor freight gravity feed gun without thinning..... ?
Though I used a white epoxy paint on my current tear to match my van, I am getting visions of a woody look on my next one. Sometimes things just get me going in another direction.
I picked one of these up at the h/f store about 6 months ago because it was cheap...
http://tinyurl.com/vr33w
Actually, I would go for a better one if it would do a significantly better job...
Forgot, I talked with rot-doc about using a marine primer & paint on my next tear. They said it would work, just sand and paint over it...
I do not know if putting anything over cpes immediately is a good idea till it expells all the evaporatives. Yes, it is an epoxy, but it does have some thinners in it as well.

Posted:
Sun Oct 22, 2006 8:03 am
by Podunkfla
Although I think automotive clear properly applied would work... I think a good marine varnish would be easier to apply and prolly cost less. But the main thing I would have against automotive clear is dealing with it if (or when) it fails... You'd prolly have to sand it all off and refinish... not a fun prospect. Whereas marine varnish can be scuffed and recoated multiple times and painted with a brush. It is also a softer more flexible finish and less likely to crack over wood that moves. I think a woodie tear is a lot closer to being like a boat than a car. Just my .02
friend ~ Brick

Posted:
Sun Oct 22, 2006 9:18 am
by madjack
...another idea...in our shop we recommend MinWax ClearShield for any outdoor projects...it is a heavy bodied outdoor rated polyurethane...there isa full set(2chairs/foot rests/porch swing/love seat) that is 20+ years old Adirondak furniture on my partners deck that was sprayed with a HLVP gun and it and the furniture looks as good today as they did when first built...have no idea about compatibility with CPES...Arne, we thin about 10% with mineral sprits or a medium flash lacquer thinner...it also imparts a very warm(and slight) amber to the finish....
madjack


Posted:
Sun Oct 22, 2006 10:15 am
by jmtk
Thanks for all the ideas, everyone. Brick, do you have a favorite brand for the marine varnish? I appreciate the scuff and recoat reminder. MJ - I remember you mentioning the ClearShield in a different thread and have been giving it some thought, too.
Thanks,
Jeanette

Posted:
Sun Oct 22, 2006 11:03 am
by Bodyman
With years of experiense with automotive clear I would not recommend or use it myself over wood.
First consider the cost. Even cheap auto clear is at least three times the price of spar varnish and is almost as thin as water so would cover less area. Automotive will take much more prep time as it is less forgiving than varnish.
Yes, applied properly auto clear can be buffed to a mirror finish but also could end up a real mess. Spar varnish can be sprayed easily by thinning it just a little. In my opinion just about anyone can do a more than acceptable job with a lot less work and expense.
I don't believe any auto paint manufacturer would recomment it over wood. Spar varnish is made for it.
As far as pricing spaying a tear for a customer I would first try to talk him out of automotive but if he had his mind set I don't believe I would do it for less than$1000
Randy

Posted:
Sun Oct 22, 2006 11:22 am
by Nitetimes
Bodyman wrote: I don't believe I would do it for less than$1000
Randy
WOW! You be expensive! Last time I bought it I paid about a buck and a quarter for a gallon with hardener and reducer! A couple hours sanding your seal coat and shoot for a grand?
Mine is getting cleared, wax it a couple times a year and your maintainance is done. Can't beat it. Why would you want to varnish every couple of years when clear will last for lots of years and still look good.
I'd say if you do the prep you could take it to a lot of places and get it shot for under 3 bills.

Posted:
Sun Oct 22, 2006 11:43 am
by Leon
The last paint I bought is when I put the stripes on the pickup, and with the cost of paint ($80 for a pint) clear, catylist, reducers, etc. the bill was almost $500 just for materials. Then there was the prep time, spraying, colorsanding, buffing, etc.
$1000 would be cheap at todays prices.

Posted:
Sun Oct 22, 2006 12:33 pm
by Podunkfla
Jeanette... I personally like Z Spar Flagship Varnish or Z Spar Captain's Varnish. This is very good stuff. Flagship Varnish offers the highest ultraviolet ray protection available today in a marine varnish. Their Captian's varnish is prolly the most glossy & has UV filters too. There are other good marine varnishes as well, I just like Z-spar as do most wood boat owners. That's what they put on the Presidential Yacht Sequoia... It's sure good enough for me. There is nothing wrong with Interlux Schooner Varnish or Epifanes Gloss Varnish & others... and they are somewhat cheaper. But, this is one case where I think you get what you pay for. Z Spar cost about $24. a quart - $75. a gallon, but it covers about 600+ sq. ft. a gallon... so a quart will prolly cover a tear with at least 2 coats. Here's where I get mine:
Jamestown Distributors... a good source for marine varnishes
Z Spar Flagship Varnish
Z Spar Captian's Varnish
friend ~ Brick