Because there is no bass luthier anywhere near me, and I'm using my bass all the time so cant be without it for more than 2 or 3 days, I do my own repairs/maintenance. My latest exercise was to get rid of 14 years worth of string grooves and an excessive relief in the ebony fingerboard. I removed the nut, and used a large flat sanding block with mucho elbow-grease. I got rid of the grooves, and reduced the relief from 2.5mm to 1mm, then finished the board with progressively finer paper, ending up with 1200 grit and a polish with linseed oil. It has exceeded my expectations, and I'm very proud of my efforts. Two points: firstly, dont be afraid to do your own repairs. All it takes is some forethought, a lot of patience, and some research, which brings me to the second point. I spent a fair bit of time searching, both here and elsewhere, to ascertain what a good relief for low action jazz pizz would be, and drew big blanks. In the end I gave up and decided to shoot for a 1mm relief. What is it with luthiers? Are they a secret society, jealously guarding their secrets? I'm not anti-luthier, just amazed that nowhere could I find that information on the net. (My local library looked at me blankly). If anyone can supply a link to that sort of information, I'd like to see how close I was with my guess of 1mm. I'm running a 5mm clearance under the G at the end of the board, and it plays clean, so I think I'm pretty close. Sorry for the big rant LOL!