Question about Danish Finish on Walnut Slab

[doug giuliano]

Hello everyone,
Novice here.
I am creating a coffee table from a slab of walnut. I have planed and flattened the surface and 'sanded the sequence' up to 340. I then applied the first coat of Watco Danish Oil. Generally it looks nice and there is really great figuring in the piece. Unfortunately I am seeing dark spots that I can't explain and don't know what to do with.
They do not seem to be part of the grain, but a function of the oil (or maybe my preparation . In the first picture you can see dark areas on the top and in the second picture you can see one of the dark spots in the bottom right corner. It looks like a dark stripe working its way from the center of the table to the bottom right hand corner.

Pictures are after 4 hours of application. I applied generously, waited ten minutes, applied again, waited ten minutes, applied again, waited twenty minutes, then wiped off.

I'd love to hear anyone's advice.

My thoughts and possible course corrections as I see them:
1. Perhaps after it sets and after a few more coats, the dark areas will blend in (proceed as planned with two more coats, hope for the best).
2. Sand out the oil (is this even possible), start over, but add some shellac before the oil (Id rather not do this, but I dont want a piece with what looks to be abnormal coloring).

Any help is much appreciated.
Thanks in advance!

[sheldon pettit]

Get in the habit of applying alcohol or water or mineral spirits to the surface before applying any color or oil or finish, this will show up any unwanted abnormalities in the wood if they exist. It could be areas of wild interlocking grain that went dark, or something else. Figure in woods always go much darker than non figured areas, but i can't say for sure not knowing what it would have looked like wet to begin with. It does seem clear though that the problem with the right pick is in line with figure in one instance though. If the oil contained any black, it could have just built up in those areas more than elsewhere. don't use resin oil finishes myself.

[doug giuliano]

Thanks Sheldon.
I should also say that I wet if before the last sanding with 320. Those abnormalities did not show up. I guess there is a chance that it is 'natural' coloring, that just looks abnormal.

[Prashun Patel]

Look at it carefully? Does it look scratchy there? If yes, you have not sanded properly. If not, then it's just the natural variation of the wood.

Also, walnut absorbs and seals unevenly. It won't look 'good' until several coats in. When you first put on the DOil and it's wet and slick, does it look good? That's how it will eventually look. Ultimately, though the dark spots will be there -just with the same sheen as the surrounding wood. It's how a slab like that is supposed to look.

[sheldon pettit]

LOL, well then, if they were not present when wet, then it's not an oil problem i don't think any of the so called oil resin products have any unnatural color, just amber. Were there any signs of nails etc., in the areas where this is occurring, the only thing that comes to mind is the very slight possibility that you may have iron stains from reacting with ferrous metals and the tannin? If so, just maybe had you sanded a little more then wet down the would have become visible. Other wise right now i have no other possible answers.

[doug giuliano]

No, its not scratchy there. It seems to have been sanded properly.
It looked great when I tested it with some water and when I just laid down the oil. Although in both cases its possible I wasn't looking close enough to see the blotches. You do have to be at the right angle to see them. Also, this may to be true at all, but it seems to be a few layers into the wood, suggesting that the oil is absorbed differently, in different areas (as you said Prashun). I guess walnut slabs may look like that and I never noticed (I've spent a lot more time looking at this one than others I have seen. I sanded it by hand. That took a long time). Just want to make sure I am not doing anything wrong or I don't double-down on something correctable.

Thanks again for the help.

[Scott Holmes]

Looks like figure to me... Which danish oil are you using? Brand and color. The colored DO have pigment stain that can lodge in the latent grain. Thier "natural" has no color added.

[doug giuliano]

I am using Watch Danish Oil. Natural Finish. I will say that after another 24 hours, the dark spots have subsided a bit. Or it may just seem that way because the sheen has reduced. Maybe with more time and more coats it will all even out. And if it is the natural figure, than thats okay. Just want to make sure Im not screwing up!

[Prashun Patel]

I say just keep applying more coats (of course remember danish oil needs to be wiped on and mostly wiped off so it doesn't pool). Walnut does this to me too. In the end, if you hate the way it looks, you'll be no worse off having to remove 4-6 coats of Danish oil than 1.

[doug giuliano]

Oops, that should read Watco Danish Oil.

[doug giuliano]

Thats great to know. I think Ill sand with 320, then apply 3-4 more coats over the next 3-4 days. Ill let you know how it turns out.
Thanks for the help!