Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine represents high-precision engineering with an enhanced 1:18 gear ratio, delivering velvet-smooth and highly accurate tuning stability. Building on the classic enclosed design introduced in 1966, this updated model integrates modern innovations without sacrificing its iconic character.
Crafted with precision CNC-machined components and high-grade brass posts fitted seamlessly into the housing, each unit ensures wear-free longevity and a self-locking drive for steady tension. The permanently lubricated internal mechanism utilizes Schaller special grease, rendering the unit completely maintenance-free.
Installation is simplified through the innovative stepped M6 flanged washer, which centers the string post securely via the hollow screw and eliminates headstock tilt moment without requiring stepped drilling. Sharing identical mounting dimensions with its predecessor, it serves as a seamless direct-replacement upgrade.
| Brand | Schaller |
| Series | M6 Series |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| String Post Material | Brass |
| Button Bore Hole | 0.17 in (4.2 mm) diameter with 0.14 in (3.6 mm) drive flat |
| Weight per Single Tuner with Button (Small/Large) | Metal: 0.08 lb / 0.08 lb (36 g / 38 g), Perloid: 0.07 lb / 0.07 lb (30 g / 31 g), Ebony: 0.07 lb / 0.07 lb (30 g / 31 g) including hollow screw |
| Product Weight | 0.13 lb |
| Lubrication | Permanent grease lubrication |
| Manufacturing | CNC-machined |


















