Installation of unslotted bridge pins may require some small modifications to be made to the guitar's bridge: the bridge pin holes may need to be slotted and reamed. Various manufacturers may or may not slot and /or ream their bridge pin holes. In some cases, the pin holes may be partially slotted, but the slot depth may need to be increased to assure proper fit of unslotted bridge pins.
BRIDGE PIN HOLE REAMING
FIK brand unslotted bridge pins are manufactured with a 5 degree taper. To assure proper fit of pins in the bridge pin holes, it may be necessary to use a 5 degree reamer to ream the bridge pin holes so that the bridge pins sit at the proper height in the bridge. We recommend Stewart-MacDonald part number 3229 reamer. The reamer is a quick-cutting tool, so work slowly with it. Test fit the pin, and if it sits too high in the pin hole, do one turn with the reamer and test fit again. Repeat until the pin is at the proper height as shown below (unslotted bridge shown for clarity):
BRIDGE PIN HOLE SLOTTING
As mentioned above, various manufacturers may or may not slot or partially slot the pin holes in their bridges. Therefore, after reaming (if necessary) it may be necessary to slot the bridge pin holes. The holes should be slotted using Stewart-MacDonald part number 1299 pin hole saw. The slots can be widened to accommodate the string end windings by using Stewart-MacDonald part number 3062 needle files. A cross-section of a typical reamed bridge showing a typical slot depth is shown below:
A CORRECT INSTALLATION
Shown below is a bridge that has been properly reamed and slotted to accept a premium unslotted FIK bridge pin. This installation affords the strongest possible coupling between the bridge, string, pin, and top, resulting in the best possible tone and the best possible appearance.
Visit John Mikelson's (aka "FIK") website here for more information.
SOURCES FOR TOOLS:
Stewart-MacDonald 1-800-848-2273, http://www.stewmac.com/
Luthier's Mercantile 1-707-433-1823, http://www.lmii.com/
Both companies supply tools for the professional instrument maker or hobbyist.
Recommended Reading "Guitar Players Repair Guide" by Dan Erlewine. Comprehensive treatment of guitar set-up and maintenance for the guitar owner. Highly recommended. Stewart-MacDonald part number 3720