Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine delivers outstanding precision and smooth operation with an improved 1:18 gear ratio. Engineered to build upon the legendary standard set by the original 1966 closed machine head, it offers superior tuning stability and effortless micro-adjustments.
Every component is precision CNC-machined from high-grade materials, featuring durable brass string posts perfectly fitted into the housing for wear-free performance. The enclosed design is permanently lubricated with Schaller special grease, ensuring maintenance-free longevity and a self-locking drive that prevents slippage.
Installation is straightforward thanks to the innovative stepped M6 flanged washer, which centers the post reliably through the threaded bushing without requiring stepped headstock drilling. This design absorbs lateral pressure and eliminates tilting moments, providing robust centering across solid headstock configurations.
| Brand | Schaller |
| Product Type | Guitar Tuning Machine |
| Series | M6 Series |
| Model | M6 90 |
| Gear Ratio | 1:18 |
| Weight | 0.8 lb |
| Single Tuner Weight with Button (Small / Large) | Metal (1.27 oz / 1.34 oz), Perloid (1.06 oz / 1.09 oz), Ebony (1.06 oz / 1.09 oz) including hollow screw |
| Button Bore Hole | Diameter 0.17 in (4.2 mm) with 0.14 in (3.6 mm) drive flat |
| Post Material | High-Grade Brass |
| Lubrication | Permanently lubricated with Schaller special grease |


















