Finishing Question, Multiple Woods

Discussion in 'Luthier's Corner' started by JaredMcMahon, Nov 5, 2012.

  1. A friend convinced me to try making him a bass (it didn't take much convincing...). Now we have three basses and two guitars underway and there are three more I'd love to do.

    Setting aside the fact that I jumped into the deep end of the pool head-first, one of my builds is a wenge neck-through with mahogany (khaya) wings and wenge caps across the top of the body, making for a uniform deep chocolate look across the entire front of the instrument. I plan on doing some sort of minimal black dye wash across the caps to make it a bit darker and more even, but beyond that I'm very happy leaving the wood as natural as I can manage, and from what I've read about wenge, it really doesn't need much to keep it stable and happy. However, most of the volume of the body is mahogany, which seems like it should receive more TLC in terms of smoothing and protection. Seems like I have two options:

    1. Find the finish that will protect the mahogany while leaving it as natural looking as possible, and finish the entire body with it.

    2. Finish the wenge minimally (Tru-Oil or some-such), then mask it off and finish the mahogany in an entirely different way as appropriate.

    Secret Option 3. I have no idea what I'm talking about and I need to do something entirely different from the above.

    Anyone care to offer up opinions/tips on finishing when the build involves several substantially different woods?
  2. Dean N

    Dean N Supporting Member

    Jul 4, 2006
    Pittsburgh, PA
    I'm no expert here, but get this and read it and make sure you understand it. And save every bit of wood scrap/cutoff and be prepared to practice on them - a lot - to find out what will create the finish you want. Figure this out (by hands-on testing) before you go and put stuff on the instruments.

    There's unbelieveable amounts of info in the old build threads. You have lots of reading to do. Lots.

    For your first run at finishing, a wipe-on varnish will probably get the most recommendations here. Tru-oil, or a wipe-on polyurethane, or similar. Did I say you have lots of reading to do? :)
  3. I've been slow to get going on the woodworking front in general and the instrument building front specifically, but I've been building up my library for a good while now. I have a copy of Flexner, which is considered mandatory reading by most of the info sources I've come to trust, but I've only skimmed it thus far. I need to sit down and spend quality time with it now that I have a real concrete application for its information. The one piece of advice I come across over and over is to not get so focused on the wood part of the project that finishing becomes an afterthought. We've invested a large amount of time and thought into these soon-to-be instruments, I don't want to ruin them just as we get to the home stretch! :O
  4. Beej


    Feb 10, 2007
    Victoria, BC
    I don't call myself a luthier, but I've definitely finished a board foot or two in my past. I suggest using a single finish. Using more than one finish, or two incompatible finishes on the same piece is definitely doable, but not for the amateur. The advice to test, test and retest above is sound... :)