Schaller GrandTune User Manual

hypertech tuning
vintage design
GrandTune
®
Installation:
Please align and drill perpendicularly from the back
of the headstock assuring a perfect 90º angle of the
drill hole.
The peghole should have a diameter of 6 mm.
Do not drill perpendicularly from the top down as
you may be working on a slightly tapered headstock.
On a tapered headstock drilling from the top down
may result in your tuner’s backplate to be tilted and
having to be forced into place by the fi xation screws
subsequently bending the tuner’s stringpost out of
line. See page 3 vs. page 4
Do not bend the base plate, the worm gear will be
irretrievably destroyed.
Thank you for choosing GrandTune tuners -
the most advanced and musical
machine heads ever built.
– 2 – – 3 –

Schaller GrandTune Specifications

General

Brand	Schaller
Model	GrandTune
Category	Measuring Instruments
Language	English

Summary

Installation Instructions

Perpendicular Drilling

Ensure perpendicular drilling from the headstock back for a perfect 90° angle.

Peghole Diameter and Tapered Headstocks

Use 6 mm pegholes. Avoid top-down drilling on tapered headstocks to prevent misalignment.

Base Plate Integrity

Do not bend the base plate, as it will destroy the worm gear.

GrandTune Bushing Requirements

Genuine Bushings

Use original Schaller GrandTune bushings for optimal performance and velvet-like feel.

Precision Diameter

GrandTune bushings feature a 6.10 mm precision inner diameter for optimal tuner performance.

Old Bushings

Old bushings should not be left in the guitar's headstock when upgrading to GrandTune tuners.

Counterbore Hole Specifications

Require 8.33 mm diameter, 6.10 mm depth counterbore holes for proper fit.

Recommended Tools

Stewart-MacDonald peghead bushing reamer (#2061) and tuner drill jig (#4858) recommended.

GrandTune Features

Technology and Options

Featuring 18:1 Velvet-Tec technology, available in various configurations, finishes, and buttons.