Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine represents high-precision engineering with an advanced 1:18 gear ratio, delivering velvet-smooth and highly accurate tuning stability. Featuring CNC-machined components and premium brass posts, these enclosed tuners provide wear-free performance and reliable self-locking gear action.
Equipped with an innovative stepped M6 flanged washer with a 0.39-inch diameter base, the design perfectly centers the string post without requiring stepped peghead drilling. This construction effectively eliminates tilting torque while relieving mechanical stress from both the post and mounting screws.
Permanently lubricated with Schaller special grease for completely maintenance-free operation, the M6 90 matches the standard installation dimensions of previous models for straightforward, drop-in replacement across various solid and slotted headstock configurations.
| Brand | Schaller |
| Series | M6 Series |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| Weight | 0.79 lb |
| Weight per Single Tuner 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 with 0.14 in drive flat |
| Post Material | High-grade Brass |
| Mounting Screw Size | M2.2 x 0.37 in |
| Flanged Washer Diameter | 0.39 in |
| Lubrication | Schaller Special Grease (Maintenance-Free) |



















