Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 sets the standard for closed guitar tuning machines with an improved 1:18 gear ratio, delivering velvet-smooth precision and exceptional tuning stability. Designed as a direct replacement for previous models, it matches identical mounting dimensions for effortless installation without headstock modifications.
Every component is CNC-machined to exact tolerances, featuring precision-fitted brass string posts and a self-locking drive mechanism. The enclosed housings are permanently lubricated with Schaller special grease, ensuring maintenance-free, friction-free operation throughout their lifetime.
Featuring the innovative stepped M6 flanged washer with a 0.39 in (10 mm) base diameter, this design eliminates tilting moments and secures proper post centering without requiring stepped headstock drilling. It relieves mechanical stress on both the string post and rear mounting screws for maximum durability.
| Brand | Schaller |
| Model | M6 90 |
| Series | M6 Series |
| Gear Ratio | 1:18 |
| Product Weight | 0.79 lb |
| Button Bore Hole | Diameter 0.17 in (4.2 mm) with driving surface 0.14 in (3.6 mm) |
| 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 threaded bushing |
| Post Material | High-Grade Brass |
| Lubrication | Schaller Special Grease (Permanently Lubricated) |


















