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Re: Strip: automotive clear coat for strip boat fi *PIC*
By:Malcolm Schweizer
Date: 4/14/2011, 10:21 pm

: I'm considering trying an automotive clear coat for my final finish
: rather than marine finish since I've got a relative with a paint
: booth and too much extra time on his hands...... Does anyone
: who's ever done this have ideas on what clear coat to use? I'm
: not sure which may or may not be compatible directly on glass.
: Any info anyone has would be greatly appreciated.

I use X-otic's UV clearcoat called (misspelling is theirs) "Sun Bloct Kleer." It is very durable, goes on easily with a cheap HVLP gun, and cures very fast. One thing to note, this product has a reducer that controls the speed of curing- NOT the activator like in epoxy. It's almost like it is a three-part polymer. Also note that you don't want to clean your gun with thinners. Run the reducer through it because lacquer thinner and acetone make this product gummy.

You can also mix their clearcoat with their Kandy Kolors (again- these people like to spell creatively)to get a translucent color that will show woodgrains through the color. Some folks asked on this forum before about how to have a colored stripe or accent and still have the woodgrain show. That would be one way to do it. If you don't like it, just sand back down to the glass and start over.

Here's a link to my wood surfboard forum where I detailed how I use small plastic cups and mark them to ensure I get a good mix. This stuff is VERY sensitive to mix ratios. It takes a 3-1-1/2 ratio. What I do is mark two cups at the same spot. I then fill one cup to that mark with water. Then I divide the water into a third cup and compare them until the water is at equal points on both cups. That is a perfect 1/2 full line. I mark that on the third cup so I now have two cups marked at one part, and one marked for a half part. Sounds complicated, but at this link it's all shown in pics...

http://www.schweizersurf.com/forum/viewtopic.php?f=3&t=3&start=30

Oh, and by the way, this stuff is about $80 a quart. You may get away with one quart, but might need two for a large kayak if you go with a lot of coats. Also note that it will melt the little plastic cups in my pics in the link after about ten minutes, so throw the cups away immediately because if you set them down on your lovely workbench you'll come back to find a big gob of melty plastic. Also note that in the pic I used a glass beaker to mix, but don't use anything you want to keep because once it sets up it's hard to get off, even on glass. In fact people use this stuff to restore plastic headlight lenses.

It is a bit sensitive to spraygun pressure because it contains a lot of solids (which makes it UV protective). You need to play with a scrap piece and dial in your pressure settings. I recommend the slowest reducer. In this pic I was using the fast reducer because I had a deadline to meet and I wanted to be able to color sand as soon as possible. (in a few hours with the fast) I find you get less orange peel when you continue to overlap over itself while it's wet, but I also find that it is very sensitive to too much reducer, so it seems the best way to get a good layup is to use a slow reducer and ensure you overlap as you spray, i.e. spraying each pass half overlapping the previous pass while it is still wet. With faster reducer in warmer weather the first pass will already be curing as you're overlapping. I hope I explained that well enough!

It is optional, but I color sand down to 2000 grit (or 1500 when the paint store runs out of 2000- which seems to happen often) and then buff it out with McGuiers buffing compounds in various grits. A good one to finish with is called "Liquid Ebony" and takes out the last swirl marks. Then use a cleaner wax to get it nice and shiny. (Check the mfg's recommendation for time between coating and waxing.)

Hope it helps!

-Malcolm

Messages In This Thread

Strip: automotive clear coat for strip boat finish
Todd O -- 4/14/2011, 6:02 pm
Re: Strip: automotive clear coat for strip boat fi *PIC*
dave g -- 4/14/2011, 8:12 pm
Re: Strip: automotive clear coat for strip boat fi *PIC*
Malcolm Schweizer -- 4/14/2011, 10:21 pm
Re: Strip: automotive clear coat for strip boat fi
dave g -- 4/14/2011, 10:55 pm
Re: Strip: automotive clear coat for strip boat fi
Bill Hamm -- 4/15/2011, 6:20 am