Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 tuning machine sets an industry benchmark for enclosed 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 and surface-finished, while the self-locking drive ensures uniform, sensitive, and dependable pitch stability.
Engineered for enduring reliability, all string posts are precision-fitted into the housing using premium brass to provide maximum wear resistance and tuning retention. The enclosed mechanism comes permanently lubricated with Schaller special grease, rendering it completely maintenance-free over years of demanding performance.
Installation is streamlined thanks to the innovative stepped M6 flanged washer with a 0.39-inch (10 mm) base diameter, which reliably centers the string post via the banjo bolt and eliminates the need for stepped headstock drilling. This smart design distributes mechanical load evenly and eliminates tilting torque on both the string post and rear mounting screw.
| Brand | Schaller |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Series | M6 Series |
| Gear Ratio | 1:18 |
| String Post Material | High-Grade Brass |
| Button Bore Hole | Diameter 0.17 in (4.2 mm) with 0.14 in (3.6 mm) drive flat |
| Single Tuner Weight with Button (Small / Large) | Metal: 1.27 oz / 1.34 oz (36 g / 38 g); Pearloid: 1.06 oz / 1.09 oz (30 g / 31 g); Ebony: 1.06 oz / 1.09 oz (30 g / 31 g) |
| Weight | 0.79 lb |
| Lubrication | Permanently lubricated with Schaller special grease |




















