Exterior Fiberglass Door

[strum456]

I am finishing an exterior fiberglass door. The door is woodgrain and will be stained prior to clear coating. At the advice of some on this forum, I have used many gallons of the Lenmar Megavar conversion varnish. I like it a lot, but I have no idea how it would hold up to the moisture and UV that it would receive in this application. I have UV clear that I could use on it, but we're looking for a satin finish. Any advice would be greatly appreciated!

 

[64avanti]

Buy a gallon of matte and mix the two. I do it all the time with clears. I was taught this years ago by a chemist at ML Campbell, a supplier of finishes to the furniture industry, now owned by Sherwin Williams.

Gloss is approx. 95 sheen
Matte is approx. 20 sheen
Satin is approx. 35 sheen

4 parts matte = 4*20=80
1 part gloss = 1*95=95
80+95=175/5=35

The ratios can be manipulated to make satin, semi-gloss, and variations in between.

 

[strum456]

I didn't realize that SPI makes a flat clear. I guess that would solve the problem pretty easily...

 

[64avanti]

I just looked it up and SPI shows a 35 sheen matte clear available.

 

[strum456]

That should be perfect. I can't find it in any of the literature, so I'll just call and ask.

 

[Julian]

I painted my door with Metallux base coat over SPI epoxy and finished with SPI UV clear mixed with SPI flatner I found at a jobber as its no longer available but some on here use Utech flatner.. Nice satin finish..

 

[Jim C]

conversion varnish is NOT an exterior coating and will not hold up. as far as i know spi discontinued their matte clear quite awhile ago. if it is available and is the same formula using the same flattener from years ago i would highly advise against using it on your door as i have done quite a few doors with the old stuff and it just didn't hold up long term. use spi universal or euro clear with utech 890 or any commonly available flattener.

 

[strum456]

Thanks Jim. I'll have to see if Chad can ship me some.

 

[Chris_Hamilton]

You can get Utech at most Akzo Nobel jobbers. There are several in your area.

 

[Jim C]

yes, be sure you get the 890. the f100 will not work in clear. its for solid ss colors only.

 

[strum456]

Would Transtar 6494 work? Chad doesn't have Utech yet.

 

[Jim C]

it says its for clearcoat. how well it works in clear is anyone's guess. the trick is having a flattener that will kill the gloss without needing so much that it makes the clear cloudy looking after applied. it will always look cloudy in the cup. i have also used hok flattener years ago. that works well in clear. as chris said, any local akzo/sikkens/lesonal jobber will have 890.

 

[strum456]

I found a quart of the 890 at a place about 20 miles away for $58.90. Maybe I'm just used to the reasonable pricing at SPI...

 

[Jim C]

that sounds quite reasonable to me. i cant remember what i paid for it last.

 

[strum456]

Thanks Jim, that is good to know. I thought it would be like a really fast reducer, and priced similarly.

 

[Jim C]

No typically its like a gel