This thread isn't about double basses, but bassoguitars; this Forum is the closest i could find in terms of relevance. And I've already girded my loins in anticipation of the drubbing I am likely to receive from the pro luthiers on here. <grin> A bassoguitar of mine has the most rutted fingerboard I have ever seen. There are grooves up to 1/16" deep and 1/8" across, and they run the full length and breadth of the fingerboard. The texture suggests a dried lake bed in a drought. The story I got when I purchased the instrument was that it belonged to a brother act that toured the OH, PA, WV carnival/state fair circuit in the 1940s and 50s. The scariest part of all this is that this damage was done with gut strings. Even the position markers have been knocked out. This is a lined fretless 'board. I don't need the basso to be a fretless -- I have two others for that -- and I hate to just trash the 'board because it still is 1/4" thick at the nut and 3/8" thick at the end of the overstand. What I would like to do is convert this bassoguitar to fretted. It does not look to be too difficult to pick out the material used to fill the fret slots. But I need to be able to fill in those ruts. The damage is too extensive to try a paste of superglue and sanding dust, and that stuff Elmer's is selling, that used to be called plastic wood, is totally unacceptable. Can anybody suggest a suitable compound that could be used to fill those ruts? I can dress the fingerboard before installing frets, but I'm stalemated if I cannot fill the ruts.