Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 tuning machine sets a benchmark for closed guitar tuners, featuring an upgraded 1:18 gear ratio that delivers exceptional tuning precision and velvety-smooth operation. Every component is CNC-machined to exacting tolerances, surface-finished for premium durability, and driven by a self-locking mechanism that ensures smooth, sensitive, and rock-solid tuning stability.
Crafted from premium wear-free brass, the string posts fit seamlessly into the housing to guarantee maximum structural integrity and pitch retention. The stepped M6 collar washer centers the string post reliably over the banjo bolt without requiring a stepped headstock hole, eliminating tilt and removing mechanical stress from both the post and mounting screw.
Permanently lubricated with Schaller special grease for completely maintenance-free performance, the M6 90 shares the identical mounting dimensions of its predecessor for a seamless drop-in replacement on standard guitars.
| Brand | Schaller |
| Series | M6 Series |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| String Post Material | Brass |
| Button Bore Hole | Diameter 0.17 in (4.2 mm) with 0.14 in (3.6 mm) drive flat |
| Weight per Single Tuner with Button (Small / Large) | 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) |
| Total Weight | 0.79 lb (0.36 kg) |
| Lubrication | Permanently lubricated with Schaller special grease |




















