Schaller M6 90 Guitar Tuning Machine
The Schaller M6 90 sets a high benchmark for closed tuning machines, offering an improved 1:18 gear ratio for exceptionally precise and smooth tuning action. Designed to fit the identical installation dimensions of original predecessor models, it allows seamless upgrades without modifications.
Every component is CNC-machined to exacting tolerances, surface-finished, and fitted with high-grade brass posts to deliver optimal tuning stability and zero-wear durability. The self-locking internal drive and permanent lubrication with Schaller special grease ensure maintenance-free performance.
The innovative stepped M6 flanged washer centers the string post reliably without requiring stepped drilling in the headstock. This configuration eliminates tilting moments and relieves tension from both the post and the rear mounting screw.
| Brand | Schaller |
| Model | M6 90 |
| Product Type | Guitar Tuning Machine |
| Gear Ratio | 1:18 |
| Post Material | Brass |
| Weight per Unit 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) |
| Button Bore Hole | Diameter 0.17 in (4.2 mm) with 0.14 in (3.6 mm) drive flat |
| Lubrication | Permanently lubricated with Schaller special grease |
| Mounting Screw Size | M2.2 x 9.5 mm |
| Flanged Washer Diameter | 0.39 in (10 mm) stepped |



















