Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 guitar tuning machine delivers exceptional tuning accuracy and velvety-smooth operation with its advanced 1:18 gear ratio. Designed with CNC-machined components and high-grade brass string posts, these closed-type tuners provide unmatched tuning stability, wear resistance, and a self-locking drive mechanism.
Featuring the innovative stepped M6 flanged washer with a 0.4 in (10 mm) base diameter, installation is seamless and requires no stepped headstock drilling. This smart design centers the string post securely through the banjo bolt, effectively eliminating tilt momentum and relieving mechanical stress on both the post and rear mounting screw.
Built to the identical mounting dimensions of its classic predecessor, the M6 90 allows for direct drop-in replacement without instrument modifications. Each sealed unit is permanently lubricated with Schaller special grease to guarantee long-lasting, maintenance-free performance.
| Brand | Schaller |
| Manufacturer | Schaller GmbH |
| Series | M6 Series |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| Weight | 0.79 lb |
| Single Tuner Weight (Small/Large Button) | 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 Hole Diameter | 0.17 in (4.2 mm) with 0.14 in (3.6 mm) drive flat |
| Washer Base Diameter | 0.39 in (10 mm) |
| Post Material | Brass |
| Mounting Screws | M2, 2 x 0.37 in (9.5 mm) |
| Lubrication | Permanently lubricated with Schaller special grease |


















