Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine delivers outstanding precision and tuning comfort with its refined 1:18 gear ratio. Continuing the legacy of the original closed-type tuner introduced in 1966, this model incorporates modern engineering enhancements while preserving its iconic performance and feel.
Every component is CNC-machined to exact tolerances and surface-finished for smooth operation, paired with a self-locking drive and premium brass string posts that provide maximum tuning stability. Permanent lubrication with Schaller special grease ensures complete, maintenance-free reliability over years of use.
Installation is straightforward thanks to the stepped M6 collar washer with a 0.39-inch (10 mm) base diameter, which centers the post via the banjonut and eliminates the need for stepped peghead holes. Designed to share identical mounting dimensions with its predecessor, it serves as a direct drop-in replacement for effortless guitar upgrades.
| Gear Ratio | 1:18 |
| Product Weight | 0.79 lb |
| Weight per Tuner (Small/Large Button) | Metal: 1.27 oz / 1.34 oz (36 g / 38 g); Perloid: 1.06 oz / 1.09 oz (30 g / 31 g); Ebony: 1.06 oz / 1.09 oz (30 g / 31 g) including banjonut |
| Button Bore Hole | 0.17 in (4.2 mm) diameter with 0.14 in (3.6 mm) drive flat |
| Post Material | High-Grade Brass |
| Manufacturing Process | High-Precision CNC Machined |
| Lubrication | Permanently lubricated with Schaller special grease |
| Washer Type | Stepped M6 collar washer, 0.39 in (10 mm) diameter base |
| Mounting Screws | M2.2 x 0.37 in (9.5 mm) |




















