Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 sets the benchmark for closed guitar tuning machines with an advanced 1:18 gear ratio engineered for smooth, highly precise tuning stability. Each component is CNC-machined to exact tolerances, delivering a self-locking drive mechanism that ensures balanced and sensitive adjustment.
Equipped with high-grade brass string posts fitted seamlessly into the housing, this tuning machine provides wear-free operation and exceptional longevity. All closed units are permanently lubricated with Schaller special grease, rendering them completely maintenance-free across their lifespan.
Installation is streamlined via the stepped M6 collar washer with a 0.39 in (10 mm) diameter base, which centers the post through the banjonut and removes lateral tilt without requiring stepped headstock drilling. Matching the installation dimensions of its predecessor, the M6 90 offers seamless retrofitting on compatible solid headstocks.
| Brand | Schaller |
| Series | M6 Series |
| Model | M6 90 |
| Gear Ratio | 1:18 |
| Post Material | Brass |
| Lubrication | Permanently lubricated with Schaller special grease |
| Button Bore Hole | 0.17 in (4.2 mm) diameter with 0.14 in (3.6 mm) drive surface |
| Collar Washer Diameter | 0.39 in (10 mm) |
| Single Tuner Weight (Metal Button) | 1.27 oz / 1.34 oz (36 g / 38 g) |
| Single Tuner Weight (Perloid/Ebony Button) | 1.06 oz / 1.09 oz (30 g / 31 g) |
| Product Weight | 0.79 lb |




















