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Warped quilt maple top

Discussion in 'Luthier's Corner' started by Tommy Gunz, Sep 24, 2004.

  1. Friend of mine gave me a bookmatch set of 1/4" thick quilt maple top. Beautiful looking but they're warped (in one direction). Is there a way to straighten them out? I could send down both side until I get flat surface but I'll probably lose about 1/3 of the original thickness. Thanks for any advice.
  2. I bought a top set of curly red maple (5/16") that was similiar but it had warpage in a coupla directions. I fixed it and it wasn't that hard to make happen. What I'm about to tell you is NOT a tried, true, legitimate method of flattening the boards but it worked for me.

    I bet I catch hell for this from Larry Davis...

    I simply dropped the boards in my pool overnight. Chlorine was way down so I didn't fear anything from that. I let them soak then I took them and sandwiched them between 3 large pieces of 3/4" MDF - 1 in the middle and 2 on the outsides. With the boards trapped between the MDF, I socked it all together with long drywall screws at 2" intervals all the way around the perimeter of the MDF. Then I took this "pack" and set it on the oil filled heater in my shop set on low. This is just warm enough to dry things but certainly not hot. For 2 days I constantly flipped the boards over to even out the warmth. I didn't want the water to stay there long enough to mildew. The MDF is pretty absorbent and the heat just helped things along. After 2 days of forced drying, I set the pack on the shelf and left it for several weeks. When I remembered it was there again - :rolleyes: - I took a looksee and the boards were absolutely flat, dry, and ready for glue. I haven't use them yet so I just keep them in between the MDF until I do.

    Hope this helps.
  3. KSB - Ken Smith

    KSB - Ken Smith Banned Commercial User

    Mar 1, 2002
    Perkasie, PA USA
    Owner: Ken Smith Basses, Ltd.
    It's best to split the top woods just before glue-up. If not, keep them slightly oversized and flat-stacked or in a press. If you need to split wood and have it settle, then leave them way oversized so you have room to work them later. We never final thickness any piece of wood until we are ready to glue them up.

    Some times our Crotch Walnut pieces warp while drying. This also happends to pieces on top of the stack with less weight on them. I have done two different things to fix this.

    1) If ther are too warped to joint, plane and split, I wet them in the sink with hot water. The ends and crotch figure area is waxed so I scrape the wax to let some water get in. Then I place them in a press and clamp them down. Each day I put more pressure as the 5/4' x 6" x 24" (approx) pieces flatten and 'give'. When I can process and split them, I do and press them again until they are flat enough to make the final thickness. Remember, these pieces were dried by air and heat for several years and are very stable. They rarely 'spring' when split open.
    2) If we can split them at first, we do only the final step as mentioned before.

    Note: I have only done this on a few occassions but with good success. One time a piece of twisted Crotch Walnut cracked in half when I tightened the press with too much force. You must let the wood give or it will break........
  4. Very interesting ideas. I'll give it a try with the wet 'n' press method. Thanks!
  5. FBB Custom

    FBB Custom TalkBass Pro Commercial User

    Jan 26, 2002
    Owner: FBB Bass Works
    I would think you could get 1/4 maple to flatten out with clamping pressure during glue-up if it was jointed and planed before it warped.