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I am making a Unity Cross for my daughter's upcoming wedding. Here's a picture for reference. There are several parts to this piece. The base, the inner cross, the outer (framed) cross, and the three "nails". The entire piece will be disassembled for use in the ceremony. The outer/framed cross is a laminate of air dried walnut/maple/walnut and the inner, scrolled/lightly carved cross is curly maple. The base will be solid padauk taken from an 8/4 board given to me by a friend many years ago. I think this piece is going to be a finishing nightmare. When I got the padauk board, it was bright red, but over the years, it turned brown (I assume from UV). I've planed the board down and the red color has emerged (as I expected) and I want to keep that color to maintain the Christian theme of the piece (representing the blood of the Christ). However, I want as "light" a finish as possible, so a lot of the finishes that contain UV inhibitors are not good choices. Like I say, I think this is going to be a tough finishing project. I want to keep the red in the padauk and the maple as white as possible. Each of the parts and pieces of this come apart, so they can be sprayed, but the carved inner cross may be a bit tricky. It may be an option to spray the two crosses with a different finish than the base. I'll simply use rattle can gold spray paint for the nails. What do folks recommend for keeping the red color of the padauk from fading over time? Is this a finish I can also use on the crosses that will allow the maple to stay white? I am considering having the two crosses professionally sprayed with lacquer. Sorry for the rambling on this. I guess I am saying that I'm open to suggestions. Thanks. Blaine
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My suggestion, after applying the expensive UV inhibitor finish you get from a marine supply store (in other words, not Minwax Helmsman), is to store it in a dark place.
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I've actually had MUCH better luck on redwood with Minwax Helmsman than with the expensive stuff from the boat store. The stuff has lasted at least 3 years while the marine stuff failed in less than a season. The expensive stuff sure went on well, though, and was a lot nicer looking while it held up. Yeah, keeping it in a dark place will help, but the top shelf of my wood rack, where the padauk was stored, isn't exposed to direct sunlight at any time. It is, however, exposed to fluorescent lighting, which does produce some UV. The piece still turned a reddish brown. Looks like the only thing I'll be able to do on this is put some kind of UV inhibiting finish on. That said, is there one of the finishes that is "thinner" than others? The marine varnishes are typically pretty thick and I hope not to "build" a finish on this. It is, after all, an indoor piece. Blaine
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What you want is a waterborne finish with good UV inhibitors e.g. Crystalac Poly-Ox, GF High Performance. They are far easier to apply than a marine finish. As you want the grain in the wood to stand out I'd first apply a coat of shellac , Ruby or garnet shellac would work well. A single 1# coat will not change the color much at all bu subtly bring up he grain. Test first to see what you like. Both shellac and waterborne finishes spray great. (BTW you can' spray most spar varnishes.) Shellac does not have UV inhibitors so you need to topcoat with something which does. UV inhibitors breakdown as they work, but if you keep it out of direct sunlight the color should be intact for years.
homo homini lupus
"The best lack all conviction, while the worst are full of passionate intensity." Yeats
Si vis pacem, para bellum
Quodcumque potest manus tua facere instaner opere Ecclesiastes
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I found an article that said clear shellac was best at keeping the color of padauk intact, so your suggestion of a light cut beneath the top coat would work. Water borne acrylic was the next best material. The article compared a whole bunch of finishes, but none of them had UV protectors.
Have you actually used the Crystalac? Can it be wiped on? The base of this piece is only going to be about 5 x 9", so I'm not sure it's worth trying to spray (I'd have to get somebody else to do that anyway). Does it leave a "thick" coat like a varnish or poly? I know those will eventually off-gas and become thin, but I'd prefer something that's thin to begin with. The wedding is in December, so there is some time, but not a whole lot. I really fear that it's gonna take me a while to carve the inside cross and I don't want to take too many chances with a new finish.
I looked up the Chrystalac, but the places I found that sell it don't have a whole lot of info on them. That's pretty typical of vendors.
Blaine
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The most effective solution is to toss the paduak and go with a nice red bloodwood. Padauk will turn brown no matter what you put on it.
Cellulose runs through my veins!
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I have used a lot of Crystalac and like it a lot. GF and Crystalac are the only waterborne finishes I have used. I would use a foam brush rather than wipe although they will wipe on. Crystalac builds a very thin coat, in fact a single coat of Crystalac is one coat followed by a scuff sand after ~30 minutes and then a second coat.
McFeeleys used to have more information online but when they changed hands the new owner built a new website it disappeared.
homo homini lupus
"The best lack all conviction, while the worst are full of passionate intensity." Yeats
Si vis pacem, para bellum
Quodcumque potest manus tua facere instaner opere Ecclesiastes
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SteveS said:
The most effective solution is to toss the paduak and go with a nice red bloodwood. Padauk will turn brown no matter what you put on it.
That's what I was thinking later, I mean if keeping it red to simulate the blood of Christ is the important thing, and since bl0odwood is redder than padauk.
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Thanks JR. I'll probably get some Chrystalac and brush it on. As for using the padauk instead of bloodwood, well, I already have the 2" thick padauk and I'm a cheap bastage. Actually, I did think about buying bloodwood for this, but there's some significance to all the wood on this project. The walnut was part of a big haul that I helped a former friend move out of a barn, the maple is from the WN auction a couple years back and this is leftover from something I made for my other daughter's wedding, and the padauk came from another friend who helped move that walnut and has remained a good friend. I love that I can provide a bit more meaning for this particular piece with the wood used. Since it's for the wedding of my first-born, I like the idea of the symbolism that the materials provide. The padauk was very red when it was given to me. It took a few years for it to turn red-brown even while unprotected. If the piece stays red for a few years longer with some Chrystalac on it, I'm good with that. Blaine
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