Psst... Ready to join TalkBass and start posting, make new friends, sell your gear, and more?  Register your free account in 30 seconds.

Advice on curing this piece of wood?

Discussion in 'Luthier's Corner' started by Tim Barber, Oct 16, 2003.


  1. Tim Barber

    Tim Barber Commercial User

    Apr 28, 2003
    Serenity Valley
    Owner: Barber Music
    I got this piece of redwood on ebay. It's about 16" by 21" by 1.75" thick, and I plan to resaw it into 3 top sets. It was air dried about 9 months before I got it and the edges were waxed, but since it arrived in my dry climate it has started to develop a few small cracks. My question is, should I let it sit as is for a few months, or should I resaw it now and let the sets dry, which I presume would take less time?

    [​IMG]
     
  2. RyanHelms

    RyanHelms

    Sep 20, 2003
    Cleveland, OH
    Man, that's a beatiful looking board. Hope you can use it.
    Anything I've seen air dried has been out for at least a year, if not much longer. I really don't know about redwood, though.
    Funny I should find this post right now, I was just about to ask the same thing concerning air drying compared to kiln dried.
    Keep asking around.

    -RH
     
  3. Suburban

    Suburban

    Jan 15, 2001
    lower mid Sweden
    Itwould indeed dry quicker. Which would increase the risk for cracks, if I'm correctly informed.
    Catch 22, right?

    How do you cope to work with that piece without getting seasick?????:bawl:
     
  4. Tim Barber

    Tim Barber Commercial User

    Apr 28, 2003
    Serenity Valley
    Owner: Barber Music
    I'll just close my eyes while I'm sawing it.

    z
    z
    z
    z
    z
    z
    z
    z
    z
    z
    z!
    !!!
    ...oops. Oh well, I didn't need that finger anyway... :D
     
  5. Carey

    Carey

    Jan 18, 2002
    Redlands, CA
    You can let it sit as it is, but it will take longer than if you resaw it.
    I'd resaw it. Redwood dries pretty fast and if you cut it down into 1/4" slices it shouldn't take more than six months to be useable.
    Are you familiar with "stickering"? It's where you stack the wood with little spacer sticks...
    read this article- http://www.alliedlutherie.com/dryingwood.htm
    It's about Brazilian Rosewood in particular, but a lot of it will apply to the redwood. The redwood will just dry a lot quicker.
    According to the article your redwood may be ready to go a lot sooner than six months. I guess it wouldn't hurt to buy a moisture meter if you're going to be buying wet wood from time to time...
     
  6. RyanHelms

    RyanHelms

    Sep 20, 2003
    Cleveland, OH
    That would be my guess, but I was waiting for someone else to say it first.

    I s'ppose stikering and weighting (and waiting...) would do the trick nicely.

    -RH
     
  7. pilotjones

    pilotjones Supporting Member

    Nov 8, 2001
    US-NY-NYC
    I believe cracking is caused by uneven drying. This is why the ends get waxed- because otherwise the ends dry faster than the middle.

    Slowing down the drying should reduce the incidence of cracks, since this causes the moisture content to be more even throughout the board. When it dries too quickly, the surface is drier as compared to the core. Drier equals contracted, so the surface is in a state of tension, and it cracks.

    Because of this, it is quite likely that a thin board will have fewer cracking problems. Not because it dries faster, but because the moisture content would be more even throughout. (A thin board essentially has no "core" zone to be at a different moisture content than the "surface zone" - it is, to a greater extent, "all surface.") I believe this is born out by things I have read - that the thicker a board is, the harder it is to dry successfully.

    For example, I was just reading that when a craftsman is going to make a turned bowl, he buys green wood. This is beause is is impossible to dry a large cube of wood without it cracking. He turns it to approximate size, incruding hollowing the center, with the walls a little thick to be cleaned up later. He then waxes all endgrain, and lets it dry, often inside a paper bag to slow down the drying.

    BTW that is a gorgeous board! I haven't seen a piece of curly redwood yet that I didn't like. The slightly diagonal wave would make it really nice for a full-width top on a body the is J-shaped, or otherwise has the same kind of offset flow to it.

    EDIT: dumb typing mistakes
     
  8. Tim Barber

    Tim Barber Commercial User

    Apr 28, 2003
    Serenity Valley
    Owner: Barber Music
    Thanks for the interesting replies, everyone :) I'm leaning toward resawing it now.

    pilotjones, I would love to cut some full-width tops out of it. Unfortunately my bandsaw won't take the full height, and the going rate at local lumber stores/cabinet shops is a minimum $60 charge, even if it's just one cut! :bawl:

    I may have to split it to saw the veneers, and then glue them up in their natural orientation instead of bookmatched. :meh:
     
  9. I like your explanation...The only thing I might be wary of is warping after resawing. This isn't a hardwood and it's curly to boot so resawing at this stage of drying might allow the smaller pieces to warp. Right now, the stresses in the block are holding it together flat. It's just that it's hard to judge what will happen with heavily figured pieces.
     
  10. Suburban

    Suburban

    Jan 15, 2001
    lower mid Sweden
    Pilot, I love your explanations, pedagogic to the bone!

    My statement above may be a conglomerate of Peters and Hams posts.
    When you dry a thin board, you always put it in some kind of press, to avoid warping. (in my area, this is so common, that it goes without saying - sorry for all and any confusion on that part).
    Then, when drying, the board will still try to warp if its prone to that. When the press stops thw warping, the fibres will instead separate (crack).

    So, a thinner board may dry nicer - or try to warp and then crack...while a thicker board, as impressively (indeed!) elaborated by Pilotjones, will tend to crack due to humidity variations.

    Catch 22....unless your material is warp free!
     
  11. Tim Barber

    Tim Barber Commercial User

    Apr 28, 2003
    Serenity Valley
    Owner: Barber Music
    Well, I had to wait longer to resaw this wood than I wanted, due to my bandsaw breaking down. By the time I got it fixed, the wood had forced the issue by developing several deepish cracks :( . But I was able to saw it into 4 usable (I think) topsets about 0.25' thick. The outside of the original board appeared dry, but when cut open the inside was literally wet to the touch...no wonder it was developing stresses!

    I stickered and weighted the resawn pieces (thanks for the article Carey) and they seem to be drying nicely with no further cracking. Interestingly, however, in each of the 4 bookmatched sets, one side has remained straight while the other has developed a significant bow which I will have to deal with somehow.

    Anyway, thought you might be interested in the progress.

    [​IMG]