Finishing very dry spalted bowl

[Eric Gourieux]

I posted a while back about tear-out with this bowl. I've finished turning without needing any stabilization, etc and now its been sitting on my bench for months. I'd like to apply a finish and was wondering about Antique Oil Finish. I think I've read about somebody SOAKING in AO rather than the typical application. Has anybody soaked in AO? Do you have any other recommendations now that it is sanded and ready to finish? I guess I could spray lacquer. I think that shellac would just be a mess with the voids but could be corrected on this. The wood is very dry and light weight. I didn't re-measure but it's about 8x4"

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[Bob Bergstrom]

I dom't think any would be bad, but if you spray it with a glossy finish any rub back the gloss, it will show up in the voids. If spraying, use a flat lacquer. I have mixed sanding dust from the bowl with lacquer to fill pours and small voids. Also have used a darker mix of dust and lacquer over or under the previous filler. I don't level it even to the surface. It looks too much like a patch. Enough to fill 85% or so, but give it a natural look. Just plain oil will work, but will induce more yellowing

[Nathan Hawkes]

Eric, I use Antique Oil a LOT, on lots of bowls. I've stopped using it on extremely spalted, light woods. It has a tendency to "muddy" the delicate lines of spalting and make the colors really run together. It also will not fill surface voids by itself. It yellows dramatically on light colored spalted areas. I'm much more fond of using a tung-oil based product for lighter colors and wet-sand with it to try and fill the tiny surface voids and areas that seem to keep absorbing finish over and over creating dull spots. The slurry of dust is the only way you're going to get those areas to blend in.



In regard to tear out on spalted woods, the method I prefer the most of all is to get as close to a finish quality surface on the outside of your bowl, then use a CA glue, medium-thin, or thin (not "super-thin" watery, but just a tiny bit of viscosity to it, concentrating on the areas that tear out heavily. Re-apply over and over until those areas won't absorb any more CA glue. Try not to use any accelerator during this process until it has had a chance to cure naturally for at least a few minutes. It REALLY has a tendency to foam up and smoke. After you have prepared the surface with glue, using a really sharp tool, take the finest wispy angel-hair cuts that you can, taking away only enough wood to remove the super glue on the surface. Sharpen again. Using a steep, almost vertical angled shear cut, work up to removing all the tear-out traces.

Repeat this process on the inside of the bowl, working in stages as you hollow the bowl, remembering to leave enough wood to be able to remove enough material to get rid of the tearout. Don't just turn it to a consistent thickness all the way to the bottom of the bowl without stopping frequently to check your surface.

The process I'm advocating here is definitely labor intensive, but it's worth it. 2012-12-02 16.38.23.jpg2012-12-02 16.41.05.jpg2012-12-02 19.17.50.jpg2012-12-02 19.18.22.jpg2012-12-02 19.18.41.jpg


The pictures are a little crude, but I happened to be working with wood just like you described. The surface is cut perfectly cleanly, and I've focused on the end grain in the pics. The bowls are unsanded and unfinished still, but the blanks were absolutely crumbly before the process I've detailed above. The wood is Hackberry, from a Presidential home. They'll be delivered to the Monticello Museum shop when finished.

Post-script; the bowl shown in the left corner of the bandsaw table is full of dust and appears to have tearout all over the side grain. I assure you it is cut nearly as cleanly as the exterior. The only spots that show any crumble are on the surface rim, which will be charred to highlight the edge.

[Prashun Patel]

Personally I would finish it with a super blonde shellac. Oil finishes will yellow it more than super blonde shellac.

Also, antique oil will likely not dry as hard especially if you soak in it. A few coats of shellac will harden and seal the punky areas much like CA will.

The only caveat with shellac is that it's tricky to get to a high gloss. If you don't care about that, then I think it's a fine choice here.

[robert baccus]

Heavy bodied sanding sealer rubbed on straight outa the can does miracles for rough wood. It acts as a sealer but also as a clear filler. Several coats followed sanding and laq. will usually give you a good finish. You can buy flattener to add to laq. if needed. For a gloss wetsand gloss laquer and buff on the lathe with auto compounds.