Adjustment of cross screw nuts presents several problems. Nuts are made of unhardened steel which is soft and easily damaged. Slots tends to be very thin,
yet the nut is approximately 3/8" (9mm) wide. As a result, standard slotted screwdrivers don't properly fit. Large slotted screwdrivers would be preferred due to greater width, but their tips are typically too thick to fit into the nut's slot. Smaller screwdrivers may provide a better fit but only contact a small portion of the slot with damage likely after several uses. For best-case adjustment of cross screw nuts, CruzTOOLS developed the GrooveTech Standard Truss Rod Driver, with a tip designed to firmly fit into the entire slot width. If you have a cross-screw equipped instruments, this should be in your tool box.
While we recommend removal of the neck and use of our Standard Driver, there's times when quick minor adjustments are desired. We developed the Cheater Driver for this purpose, with the same tip profile as our Standard Driver but
reduced to 4mm width to fit the exposed portion of the slot. Since adjustments will be made with the neck attached, a long 175mm shaft allows easy access to the nut and an oversized handle provides necessary grip
for the relatively high torques needed.
Recommendations for Use
1. Your truss rod and nut should be in good working order - this should not be the first time you've made a truss rod adjustment!
2. If you haven't done so recently, remove the neck and then remove the nut. Inspect the cavity and clean it out using a dry Q-Tip cotton swab. Apply one drop of machine oil or a very small dab of petroleum jelly to nut threads for smooth rotation.
3. When properly adjusted, the nut face should be approximatley flush with the neck butt. If it's recessed, there may be other problems such as compressed wood which should be evaluated by a professional guitar technician.
4. Adjust the neck for proper relief (curvature) using our Standard Truss Rod Driver. Our GrooveTech Guitar or Bass Player Tech Kits can also be very helpful in measuring for proper relief (see our
Easy Setup Guide for full setup details). This may take several rounds of neck removal, adjustment, and replacement, but it's necessary. You'll now have a baseline set-up and be ready for future minor adjustments using the Cheater Driver.
5. Keep in mind that you're adjusting using only a 4mm wide portion of a soft metal slot. Since you're forcing a change in neck curvature, resistance is high - especially if you're tightening the nut (which flattens the neck). The result is that a number of factors work against damage-free adjustment so care must be exercised.
6. Nut slots vary in width and depth. In general, vintage nuts tends to be more narrow and deep while reproduction nuts have wider slots and shallow depth. We took this into consideration when designing the Cheater Drive tip profile. Regardless, its very important that the tip firmly fits into the exposed slot. If you experience excessive free play, you should probably remove the neck and use our Standard Driver for adjustment.
7. Place the tip in the outside half of the slot so that the entire tip is in contact with nut material.
8. Make small adjustments at a time without forcing nut movement. A firm, steady force works best.
9. If your nut has been chewed up from previous use, you probably should remove the neck and use our Standard Driver to prevent further damage.
The Cheater Driver is a useful addition to your tool box. With that said, CruzTOOLS recommends use of the Standard Driver whenever possible. CruzTOOLS isn't responsible for damage from use of the Cheater Driver, so please use with care and common sense.