Fingerboards: How thin is too thin?

Discussion in 'Setup & Repair [DB]' started by Eric Jackson, Aug 20, 2004.

  1. I have a playability issue with my bass involving the fingerboard. The string height of the D and A strings is too high. (Notice I didn't say 'action'.)

    Unstrung, the scoop in the (bevelled) board runs about .4 mm (measured with a digital vernier and a precision straightedge). Strung to pitch, the scoop runs about 2 mm. The radius is pretty consistent at 90(!) mm, far flatter than the 66 mm or 70 mm prescribed by Bob Branstetter and Bob Ross respectively. The top of my bridge was recently reshaped by a pro to roughly 75 mm radius. Also, the board's getting thin- overall thickness at the neck root overhang is 18.5 mm, along the edges it runs 6.6 to 7.8 mm thick where it's glued to the neck.

    Finally, to my questions:
    -Is an increase in scoop when tuned to pitch common, or is my neck getting flexy because the fingerboard's too thin?
    -Is the board already too thin at the edges to plane it to decrease the radius, thereby moving the centre of the board closer to the D and A strings?
  2. My apologies for the self-serving bump here, but I was really hoping to get a little guidance here from our resident pro luthiers, or someone who's replaced a fingerboard lately.
  3. (1) Its not unusual for the scoop to increase a little when the bass is under tension. However, going from 0.4mm to 2.0mm does sound excessive to me.
    (2) If the FB is not already too thin, IMO it will be too thin after you try to reduce the radius. You are going to be better off in the long run having your local luthier replace the board with a new one having the smaller radius you desire.
  4. Thanks, Bob.
    I've had two conflicting opinions from luthiers recently. Sounds like a new board is in order. Would probably need a new bridge at the same time. $$