These diamond abrasive files are the fastest and smoothest cutting rotary files that you can buy. Diamonds are embedded into one side of each file and the opposite side can be used as a standard for checking flatness of the tone hole (use a leak light). Leaves no chatter marks. Sharper and longer lasting than steel files. Each set comes with pilots and driver. These tools are a great timesaver for making perfectly flat tone holes.

For tone holes that you can’t reach with an Allen wrench, use a hex head bolt and closed end wrench to turn the tone hole file while applying pressure to the screw head with a Phillips screwdriver or with the ball end driver provided. You can also use an automotive type ratchet wrench with an extension. The ball end driver allows the file to tilt a little to find the correct level. Use light pressure when finishing up the largest tone holes or you will flex the tone hole and it will not come out flat.

Stop when the low spots disappear (or just before). Tone holes should only be faced once in a lifetime. Judgment is called for. After cutting tone holes, check their flatness with the bare metal side of the tone hole file (use leak light). Large diameter holes may flex and leave high spots (usually the short sides of the tone hole) and you may need to carefully rub off these remaining high spots with a small jewelers file or bit of folded fine sandpaper. Don’t just keep grinding away with the tone hole file. Never shorten the tone holes more than you have to. Beware of tone holes that are already too short from sloppy manufacture, previous filing or other damage (call for repair options).

Dress up the inside & outside burrs of the tone hole with Scotchbrite 113017 or aluminum foil to take off any sharp edges that would cut into (or grab) the pad. Although the diamonds will not wear out, the backing material can come loose or delaminate over extended time/use. Call for re-skins if this happens. The replaceable diamonds come in discs with an adhesive backing.