U V inhibitor finish ?

Doodler 2

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Hi,
Just a quick question about spar or wood finish.

I want to keep the color of the wood from fading to grey or brown.

The wood pieces are made of purple heart.

What is the best product with a UV inhibitor? Is there something better?

kent r
 
I prefer epifanes uv. There are others with uv protection; I never rated the amount of uv per mil. The wood will still fade; I don’t know what purpleheart does in sun, but sun affects all wood color despite a uv protectant.
 
Thanks,
only now do I see there is a forum on "finishes"here.

I don't know what the sun will do to purple heart yet, but I'll find out.
Was hoping to slow or stop the fading.
if that is not possible, it will be ok. Just some trim, and will blend in if brown.
kent r
 
title


Purpleheart - - - (PDF)

The linked Fact Sheet doesn't speak about the Sun or UV, but they do mention discoloration . . .

‘‘ Heartwood brown when freshly cut becoming deep purple upon exposure, eventually turning to a dark brown sharply demarcated from the off-white sapwood. ’’

However they don't specify ‘‘exposure’’ to what, UV light, or just air, or both, or partly the drying process in general, as they start at freshly cut . . ?
 
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Bright finishes are the hardest to live with in an exterior, let along a marine environment. Your species will adopt its usual "name sake" coloring with UV, but clear coats can delay this for a time, longer if this coating is maintained. This is the butt kicker, maintenance particularly on certain species, can cause you to go bald in frustration. Purple heart wouldn't be a common or typical "spar" species, though it will tolerate moisture and UV better then some other species. As to which is "best", well there's no such thing, just varying degrees of success with each product, by each user. I look for solids count and UV inhibitor percentage, but others may prefer application ease or resin type. Whatever your requirements are, the field of products shortens down, pretty much forcing your hand, eventually. I like "Bristol Finish".
 
I say go for it. The boat will have great color for probably ten years that simply softens as times goes.

Another thought would be to consider transtint. It would be very tricky to not abuse the natural color of the purpleheart, but the dyes are perhaps more resistant to uv.

I have used transtint to make walnut turn red and it is stunning as wood colors go, but tricky to get even and that might show greatly in the full sun.
 
Great,
I downloaded the PDF,
might find some transtint, had not heard of it before,
and consider expecting less, accepting the fading, or refinishing every so often.

Or, forget using it for trim, and using it to make something else, like in the PDF.

kentr
 
I did some more reading and oils turn purpleheart brown; the sun turns it purple.

I might be inclined to try a water based finish on it. I can’t recommend one cuz I am an oil guy. Some testing is probably merited.

The transtint is not 100% sun stable, but supposedly is more resistant to sun damage than other dyes. It costs about 30 bucks to test the dye. I use denatured alcohol for a solvent; so that would also probably not turn ph brown.

My project, I’d run samples of oil based, water based and tinted oil and tinted water and score them. Good luck.

You can see my video on walnut. Youtube-how to stain walnut red. In your case; the second step might turn the purpleheart brown. ?
 
Most tints and stains have no UV inhibitors in them and the only UV protection they offer, is the pigments and/or dies used. There is a new water borne clear that's had some good reviews, though I'm not sure about durability and longevity. Have a look at Pettit "SeaGold" finish and see what you think.
 
Thanks for posting the video.
I have used TransTint before for airbrushing,mixed with lacquer. Have turned maple both yellow and red, but not for a boat.

What is clearer now is where to use the purple heart. Not on a boat, unless you don't care about the color, and use it for it's rot resistance,
or other.
It was the natural purplish color that I was liking.
I will find something else to make with this wood.
Will stick with mahogany, black walnut, or teak, stained dark, for the boat trim.

Anything else made with purple heart will get some kind of UV blocking finish, and leave it indoors.

kentr
 
You can use a "Metal complex" dye to get the color you want. Metal complex dyes are the most uv resistant way to change a wood color. The dyes are powder and you can use alcohol or distilled water depending on your skill level (the alcohol is harder to use because it evaporates so fast). After the dye you can use a clear epoxy with UV resistance. Final finish with a UV resistant varnish and you can replace the varnish every couple of years and the color won't fade at all.

W. D. Lockwood Metal Complex Dyes https://www.toolsforworkingwood.com/store/item/LW-MCW.XX/W._D._Lockwood_Metal_Complex_Dyes

This is my runabout that I did new decks on, and matched the decks that were okoume (which is pretty pale) to the sides that were a mahogany plywood... This is before I rubbed out the varnish, but I was pretty pleased with the color. I used a custom mix of Lockwood mahogany dye (the Houndoras Brown and the Colonial Dark Red) and got a good match.

UV protection is a way of absorbing UV rays and over time the protection gets "burned out" of the finish. If you want to protect wood or epoxy, you can use a UV varnish and then periodically replace it. If it's stored inside (like my boat is) the finish will likely last forever, but if it's outside you'll need to replace the varnish every couple of years. By using a dye that is UV resistant, covering it with an epoxy with UV resistance, and then finishing with a UV varnish you've pretty much done all you can do. In reality it isn't much more work than any other finish, but with this approach you can clean off the varnish pretty quickly and not cut into the epoxy and then you won't have to touch up the stain like you would if you didn't use the epoxy coat.
 

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Now that small boat looks like one wild ride.
Beautiful finish too.

Thanks for your link.
I'm going to forget using any purple heart for boat trim. Stained mahogany or recycled teak will be fine.
While I love the natural color, I do not want to fight the sun to keep it that way.

I will use the big board of purpleheart, given to me as a Christmas present, for furniture or a musical instrument that will stay indoors.

kentr
 
Thanks, it's a APBA "D" class runabout.. The motor is a 44 cubic inch Merc built to "stock" class limits.. Class record flying kilo speeds are over 90 mph. This boat should just touch 80 mph at the end of the straights on a one mile oval course... This boat was the APBA class champion in 1981 with Mike O'Brien driving... And yes it's a rush, but it does behave pretty well...
 
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