How to finish a "mixed wood" fingerboard?

[gormsby]

I have a big chunk of mulberry that I plan to use for both a bass and a guitar body, probably tops and backs around an ash or hackberry core. The bass will be fretless with a Royal Blackwood fingerboard. For the (fretted) guitar, I'd also like a very dark board, something to contrast with the medium gold of the mulberry. I have a pau ferro board on hand, but that wouldn't be a particularly interesting contrast. So I thought of perhaps royal blackwood again, or maybe walnut. Then it occurred to me that the royal blackwood with mulberry block inlays, and perhaps edge binding, could be a rather striking complement to the mulberry body.

So then the question is -- how should I finish the face of the board? If I go with the blackwood and mulberry inlays and binding, I'd have two woods - one that is generally not topcoated with a clear coat, maybe just occasionally oiled (the blackwood), and the mulberry, which I'd put in a class with maple or cherry -- probably best to clear-coat. Try to half-way it with one of those thin wipe-on oil/poly blends? Just oil it? Or poly the whole thing, if the royal blackwood would be amenable to it? Mask off the inlays and poly just those?

Has anyone here dealt with "mixed wood" boards like this where different parts typically enjoy a different kind of finish?

If I went with walnut for the board instead, I'd just poly the whole thing -- easy. But that gold on black of mulberry/blackwood is tempting me.

 

[Beej]

I usually rub the whole surface with a thin coat of the glue, either CA or epoxy. Then I will typically use a thinned polyurethane finish, just a couple or three thin coats, and a smoothing with a scotchbrite to get an even sheen. I can't remember which I used here: https://www.talkbass.com/threads/4-...ry-maple-walnut.1487067/page-11#post-25181665

 

[Bruce Johnson]

I have a big chunk of mulberry that I plan to use for both a bass and a guitar body, probably tops and backs around an ash or hackberry core. The bass will be fretless with a Royal Blackwood fingerboard. For the (fretted) guitar, I'd also like a very dark board, something to contrast with the medium gold of the mulberry. I have a pau ferro board on hand, but that wouldn't be a particularly interesting contrast. So I thought of perhaps royal blackwood again, or maybe walnut. Then it occurred to me that the royal blackwood with mulberry block inlays, and perhaps edge binding, could be a rather striking complement to the mulberry body.

So then the question is -- how should I finish the face of the board? If I go with the blackwood and mulberry inlays and binding, I'd have two woods - one that is generally not topcoated with a clear coat, maybe just occasionally oiled (the blackwood), and the mulberry, which I'd put in a class with maple or cherry -- probably best to clear-coat. Try to half-way it with one of those thin wipe-on oil/poly blends? Just oil it? Or poly the whole thing, if the royal blackwood would be amenable to it? Mask off the inlays and poly just those?

Has anyone here dealt with "mixed wood" boards like this where different parts typically enjoy a different kind of finish?

If I went with walnut for the board instead, I'd just poly the whole thing -- easy. But that gold on black of mulberry/blackwood is tempting me.

I'm assuming that this is a fretted bass fingerboard? If so, I wouldn't worry too much about the softer mulberry inlays and binding. You could coat the whole thing with one of the hardening penetrating oils like Stew-Mac's Fingerboard Oil. That will seal up both woods well, which is the most important thing. It'll lightly amber-darken the mulberry, which could look nice. And you could wipe on an extra coat or two for a little more surface protection. Wipe the excess off the Royal Blackwood, but leave the excess on the mulberry. Let it cure for two days and then buff it up. Get the mulberry parts up to a semi-gloss, and leave the Royal Blackwood satin and "natural". That might look cool.

Or, you could give it all a heavier finish of a wipe-on poly, and work it up to a higher gloss all over. A lot more work.

Personally, I like ebony (and alternative) fingerboards in satin natural-looking finish.

 

[ddm0502]

I always disagree with the idea that any fingerboard should be left unfinished. At very least, use a few coats of a drying oil like tung or linseed. When people complain that their fingerboard looks dry, thats the sign that it should have been finished.

Soapbox rant over, I think your situation is the perfect time for the old woodworkers mantra, test it on scrap. Make up a few samples and see what you like better.

 

[mrperkolator]

I’m here for the pictures once you get there!