Adding inlays to finished work

[Prashun Patel]

I have a piece of walnut finished with Cabots Tung Oil Finish. Is it possible to add an inlay to the piece now?

My concern is that I'll need to sand the inlay flush and therefore will inevitably sand some of the bench surface. I have not dyed or stained the top.

Questions:

1) Is it possible to minimize this damage by taping before I route the inlay?
2) If I do sand through the surface of the top, can I easily repair the finish by just applying more TOFinish over the whole thing?

Thanks in advance.

[Jamie Buxton]

I'd write the existing finish off. Plan on revarnishing the entire top. You'll do a better job of the inlay work -- getting it exactly flush -- and you'll have a consistent finish across the whole top when you're done.

[Prashun Patel]

Thanks for the reply, Jamie. The thing is, it's a really a long oil finish. There's very little varnish, and no build. I was kind of hoping I could blend oil applied to bare spots into the rest of the wood. Anyway, I'll certainly test on scrap b4 proceeding.

[Hank Knight]

Shawn,

You should be able to add the inlay and finish with tung oil. The new tung oil should blend with the original finish nicely. I don't know that I would go to the trouble to tape around the inlay before routing. You're going to have to scrape or sand the inlay flush and that will cause some collateral damage to the original finish. I would make sure the surface is clean and grit-free to avoid scratching it. If there is some minor scuffing to the surronding finish, you might want to apply the first coat or two of tung oil with some OOOO steel wool. Use a soft cloth or paper towel for the last few coats. Then buff and wax. The tung oil should build nicely and blend with the original finish.

Hank

[glenn bradley]

I also would hesitate. Add-ons often look like add-ons. Unless someone is going to be royally ticked off I would save the inlay for the next effort. If you must forge ahead on this one I would prep a test piece large enough to accept a decent inlay sample, sand and finish as your existing piece was done and try the inlay and repair there. If it is acceptable, do your keeper.

[Prashun Patel]

Thanks, all. I'll test it out. Any caveats on doing inlay work?

I'm making a dutchman repair (with a butterfly inlay) to minor split in a slab of walnut. The dutchman is really for decoration, since I already pocketscrewed the split from the underside.

[Jamie Buxton]

Here's an idea you didn't ask about, but what the heck....

The traditional shape for a dovetail key is, well, that bow-tie shaped thing. However, to do its job, there's no reason that the key needs to be that shape. It just needs to be narrower in the middle than at the ends. It could be a dog-bone shape, or two circles joined by a bar, or many others. It doesn't have to be symmetrical; that is, it could be bigger at one end than at the other, or it could be, say, a dovetail shape at one end and a circle at the other.

If you're installing the key with traditional hand tools, there's an advantage to the bow-tie shape: it is easy to cut with straight chisels. However, if you're using a router and a template guide, those non-traditional shapes are just as easy to make. Some of them are even easier than a bowtie, because you don't have to clean out the corners. (All the woodworking catalogs sell little kits for making inlays like this. They have a template guide with a collar. It allows you to use just one template to cut both the hole and the inlay that fits into it.)

[Prashun Patel]

Thanks, Jamie. I've already bought the butterfly key inlay and bushing set. I've resigned myself to a little chisel work in the corners. I like the look of the bowtie.

[Roger Everett]

Thanks, all. I'll test it out. Any caveats on doing inlay work?

I'm making a dutchman repair (with a butterfly inlay) to minor split in a slab of walnut. The dutchman is really for decoration, since I already pocketscrewed the split from the underside.

You ask about any caveats -- I don't rush after it's been glued in. Unless your butterfly inlay is really thin, I find that after I flush it down w/ a cabinet scraper, in a couple days it seems to have changed a bit, and needs to be rescraped. If the butterfly is a bit thick and ends up more proud of the surface than a scraper can easily handle, double faced tape a couple runners on a router and route it down close to flush, then scrape.

Roger

[Dewey Torres]

Shawn,
Do you have a palm router?

I usually double stick tape a piece of 1/4 hard board to my Bosch colt to make a flush trim set up.

You can do this with a full size as well but the palm router is better suited.

Set the bit depth with a piece of paper or masking tape and it will never touch the original finish while keeping the inlay only a "piece of paper" proud. I usually don't mind leaving a butterfly proud as it pretty much screams "this isn't fake" as soon as someone takes the time to run a finger over it.

See my album on the wine cork display to get a general feel for what I did.

Also, if you are not sure what I mean about the flush trim setup. I can send a pic or illustration.

[Prashun Patel]

Roger/Dewey-
Thanks for those tips. Yes, I have a trim router. I never thought of using it like this. I'll definitely give it a whirl.

In the worst case, resanding and re-finishing is no big deal.