Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine delivers precise tuning and comfort with an advanced 1:18 gear ratio. All components are CNC-machined to exact tolerances, finished for durability, and equipped with a self-locking drive for smooth and uniform operation.
Crafted with premium brass string posts carefully fitted into the housing, these tuners offer superior tuning stability and wear resistance. Each closed unit is permanently lubricated with Schaller special grease for completely maintenance-free performance.
Featuring the innovative stepped M6 flanged washer with a 0.39 in diameter, the post is securely centered through the banjo bolt without requiring step-drilled headstock holes. This design eliminates tilting torque and protects both the string post and rear mounting screw.
| Brand | Schaller |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| Post Material | Brass |
| Flanged Washer Diameter | 0.39 in |
| Button Bore Hole Diameter | 0.17 in with 0.14 in driving surface |
| Weight per Single Tuner with Button (Small/Large) | Metal (0.08 lb/0.08 lb), Perloid (0.07 lb/0.07 lb), Ebony (0.07 lb/0.07 lb) |
| Product Weight | 0.79 lb |
| Mounting Hardware Included | Banjo bolts, stepped flanged washers, M2.2 x 9.5 mm mounting screws |
| Lubrication | Permanently lubricated with Schaller special grease |


















