Waverly Mandolin Machines

Tips for installing Waverly mandolin tuning machines.


Waverly Mandolin Machines

Waverly Mandolin Tuning Machines are precision devices with very close tolerances. To get the benefits of these quality tuners, they must be installed correctly.


1. The string post holes must be in a straight line.

Double-check the holes on the peghead to be sure they're aligned (this isn't always the case, regardless of the maker). Misaligned holes put unwanted force on the tuners, so replacing old tuners may require redrilling the string post holes. The diameter of the holes should be 1/4".

2. The string post holes must be evenly spaced.

The string posts on our Waverly standard machines are uniformly spaced at 29/32" from center to center (.906" or 23mm).

3. The string post holes must be must be perpendicular (square) to the back of the peghead.

It's easy to see that holes drilled off square will force the mechanisms into an unwanted position.

We recommend a 1/4" primary peghole for these tuners, drilled perpendicular to the back of the peghead. This is very important on tapered pegheads and "reverse-gear" tuners, because it allows the tuner plate to make solid contact with the peghead. Use a drill press for accuracy.Drill some test holes in scrap wood to make sure you're in control, and test-fit the tuners and bushings for proper fit.

Drilling - Right
Drill at a right angle to the BACK of the peghead.
Drilling - Wrong
Drilling at a right angle to the peghead front won't allow the tuner base to mount flush.

4. Installing peghead bushings on the front of the peghead.

These bushings require counterbored holes that are concentric to the string post holes. The ideal tool for this is the Waverly Peghead Bushing Reamer (StewMac #2061), which creates the necessary .328"-diameter hole and has a pilot shaft which fits the string post hole.

A drill press is the best way to keep these holes square as you ream .328" diameter holes to a depth of 3/8" (.375"). Press the bushings into the peghead to test-fit the tuners. The tuners should slide in easily with the mounting plate flat against the back of the peghead. The shafts should fit firmly and turn freely, with only a little side-to-side movement.

Bushing 1
Peghead bushings require a second, wider hole on the same center (easiest method is our #3818 Bushing Reamer)
Bushing 2

5. Drill the mounting screw holes in two steps:

The small mounting screws must be carefully centered in their holes. Do this by drilling in a two-step operation:

Hold the tuner unit in position. Using a bit with the same diameter of the baseplate mounting holes, drill a very shallow (1/32" deep) starter hole for each of the five screws. Drill only deep enough for the hole to reach its full diameter.

Remove the tuner, and drill the screw holes centered on the starter holes. Use a bit slightly smaller than the size of the screw threads, and hold the drill square to the surface. Keep the holes centered. Off-center mounting screws will pull the tuners out of line, applying unwanted force. On older mandolins, the mounting holes almost never line up acceptably, so re-drilling is required.

Properly installed, Waverly tuners work smoothly and stay in tune longest — providing a lifetime of fine tuning!

For simple and accurate installation of Waverly mandolin tuners, we recommend using the following tools from Stewart-MacDonald.

Mandolin Peghead Drill Jig (StewMac #5008)

We produce this special jig for drilling correctly aligned 1/4"-diameter pegholes, to match standard 29/32" (.906") spacing.

Drill Jig

Waverly Peghead Bushing Reamer (StewMac #2061)

Our 2-1/2" long, 1/4" pilot, custom reamer is designed for slow-speed use in your drill press. Two 1" flutes cut a precise 0.328"-diameter counterbore for a perfect fit for your Waverly bushings. They'll fit snugly, won't fall out, and there's no risk of cracking the peghead.

Bushing Reamer

Waverly Tuning Machines are distributed exclusively through Stewart-MacDonald.

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