Finishing ancient kauri wood... suggestions?

[LouieAtienza]

OK so I have (or should I say, had) a decent sized slab of this stuff. I was going to use it for other things, but the 5/8" bow prevented that. So I broke this board down to guitar-friendly sized billets that I will eventually send for resawing (I use Chris Ensor in Springfield, MO, who does an exemplary job!)

Anyway, to minimize waste, I broke the board down to yield a back billet and side billet, which I hand-planed one surface flat. Removing that much bow by hand was not a fun task, and I'm still sore from it, but I do have to say that ancient kauri planes as well as any wood I've planed. For a softwood, I'm very surprised how hard the wood is.

After surfacing, I sanded the surfaces of the four billets to the recommended 1200 grit - which in of itself is amazing that the woods just powders up like hardened lacquer - and tried different finishes. I had pretty good results with shellac and lacquer, but for some reason, when the wood is held at a certain angle, the beautiful cherry-honey color disappears and fades to a weird gray. Suspecting that this could be due to the finish just sitting on the surface, I tried a UV-cured polyester finish, brushed on, left to sit to float out, then cured with UV light. WOW - the wood now almost has a metal-flake look, and the dull gray now looks like shiny titanium. It looks like color-shifting paint almost.

It's so weird, because, sanded it looks almost blah like alder - even machines like alder, though it smells like aniegre. While I like the look of the UV-cure poly, I don't like the Bondo-like smell that I have to apply inside, away from any sunlight which would activate the poly instantly.

[Ned Milburn]

Originally Posted by LouieAtienza

OK so I have (or should I say, had) a decent sized slab of this stuff. I was going to use it for other things, but the 5/8" bow prevented that. So I broke this board down to guitar-friendly sized billets that I will eventually send for resawing (I use Chris Ensor in Springfield, MO, who does an exemplary job!)

Anyway, to minimize waste, I broke the board down to yield a back billet and side billet, which I hand-planed one surface flat. Removing that much bow by hand was not a fun task, and I'm still sore from it, but I do have to say that ancient kauri planes as well as any wood I've planed. For a softwood, I'm very surprised how hard the wood is.

After surfacing, I sanded the surfaces of the four billets to the recommended 1200 grit - which in of itself is amazing that the woods just powders up like hardened lacquer - and tried different finishes. I had pretty good results with shellac and lacquer, but for some reason, when the wood is held at a certain angle, the beautiful cherry-honey color disappears and fades to a weird gray. Suspecting that this could be due to the finish just sitting on the surface, I tried a UV-cured polyester finish, brushed on, left to sit to float out, then cured with UV light. WOW - the wood now almost has a metal-flake look, and the dull gray now looks like shiny titanium. It looks like color-shifting paint almost.

It's so weird, because, sanded it looks almost blah like alder - even machines like alder, though it smells like aniegre. While I like the look of the UV-cure poly, I don't like the Bondo-like smell that I have to apply inside, away from any sunlight which would activate the poly instantly.

Are ya gonna just tease us with this, or also post photos...?? ;-)

[LouieAtienza]

Originally Posted by Ned Milburn

Are ya gonna just tease us with this, or also post photos...?? ;-)

LOL just a little... pics coming up...

[LouieAtienza]

Here's some pics Ned...

Lacquer:
[IMG]20180120_223307 by Louie Atienza, on Flickr[/IMG]

Polyester:
[IMG]20180122_115255 by Louie Atienza, on Flickr[/IMG]

Grain close-up:
[IMG]20180122_115548 by Louie Atienza, on Flickr[/IMG]

[LouieAtienza]

Original board... looks pretty flat here to me. Also, my eagle eye is trained to see this board is quartered to rift, which was a factor in purchasing:
2 CloseUp by Louie Atienza, on Flickr

The largest chunk I have, about 12" x 38". The back end is the live edge and quartered and maybe only about 1/8" bow. The closer side had about 3/8" bow with the low spot a little toward right of center:
[IMG]20180120_120452 by Louie Atienza, on Flickr[/IMG]

Nice and flat, but plain as vanilla, only vanilla has taste.
[IMG]20180120_125346 by Louie Atienza, on Flickr[/IMG]

About half of the shaving pile. The other half got blown with the wind. My triceps are still sore!
[IMG]20180120_163732 by Louie Atienza, on Flickr[/IMG]

The smaller billets were a little easier to flatten.
[IMG]20180120_144954 by Louie Atienza, on Flickr[/IMG]

The last pic is of the board on top, for reference as to in-the-white versus finished...

[dekutree64]

What sort of shellac application method did you try? If you really slop it on so it has time to soak in before drying, it should make a more deep looking finish. Wiping with a relatively dry cloth will make a surface film that prevents subsequent coats from getting into all the nooks and crannies of the wood texture. But it will never really penetrate the way oil does. Somogyi's book mentions mixing walnut oil with shellac for the first coat to get a deeper appearance, but I've never actually tried it.

Also could try oil varnish. Alan Carruth and Bruce Sexauer are the guys to ask about that.

Epoxy is another possibility. Not necessary for pore filling in this case, but some guys use it on maple to highlight figure.

[LouieAtienza]

Originally Posted by dekutree64

What sort of shellac application method did you try? If you really slop it on so it has time to soak in before drying, it should make a more deep looking finish. Wiping with a relatively dry cloth will make a surface film that prevents subsequent coats from getting into all the nooks and crannies of the wood texture. But it will never really penetrate the way oil does. Somogyi's book mentions mixing walnut oil with shellac for the first coat to get a deeper appearance, but I've never actually tried it.

Also could try oil varnish. Alan Carruth and Bruce Sexauer are the guys to ask about that.

Epoxy is another possibility. Not necessary for pore filling in this case, but some guys use it on maple to highlight figure.

The UV polyester I put is similar in application to epoxy. As I haven't worked this wood before, I went relatively light with the ahellac to mitigate any blotchiing. I may revisit a shellac finish, but maybe will try the oil varnish first. I know Alan brushes his and Bruce sprays his. I don't know of any builders here that use ancient Kauri. I do know Laurie Williams and Jay Lichty use it quite a bit, but I haven't reached out to them... yet.