Weight: 4 LBS 6 OZ
Serial # 3023354
2026 CF Martin Custom Shop
Super D Sinker Mahogany
D-18 appointments , super rare 3 piece back
one of a kind guitar
Akzo Satin Lacquer finish
no pickguard
Sinker mahogany refers to genuine mahogany logs—typically old-growth timber—that were lost and submerged in waterways for decades, or even over a century. Originally harvested in Central America (notably Belize) during the 18th and 19th centuries, these logs were floated downriver to sawmills, where an estimated 25% to 30% became waterlogged and sank. Key Characteristics
Mineral Enrichment: While submerged in oxygen-free environments, the wood is preserved from rot and absorbs mineral deposits and tannins from the water. This process increases the wood's density and alters its cell structure.
Visual Appearance: It often exhibits a darker, richer patina than modern mahogany, featuring unique color streaks and deep reddish-brown hues caused by centuries of mineral exposure.
Tonal Qualities: In instrument making, it is prized for enhanced projection, sustain, and clarity
The Martin Super D-18 takes the legendary Style 18 Dreadnought to the next level. With 20% more internal air volume than a standard Dreadnought, this Super D body delivers thunderous bass, increased volume, and extended dynamic range—all while keeping the iconic silhouette intact. Solid genuine mahogany back and sides add warmth and punch, while the spruce top ensures clarity and projection. Forward-shifted Golden Era scalloped X-bracing, as featured on the Modern Deluxe Series, makes every note responsive and powerful. Appointments like black binding, abalone dot inlays, and a satin-finished neck keep the look classic and the playability smooth. Paired with an ebony bridge and fingerboard, the Super D-18 is a bold evolution of an acoustic icon—built for players who want to be heard.

Neck Frets Clear: 14 Frets Clear Body
Body Shape: Super Dreadnought 14F Body
Inspired by: True Custom - 18 Style
Appointment Level: Standard
Base Model Note: Wood selected by D-Town Guitars Sinker Mahogany #16
Adhesive: Modern Adhesive
Scale Length: 25.4"
Compensated Scale Length: 25.470"
Neck Joint: Dovetail
Top Material: Sitka Spruce
Final Top Grade: Grade 4 Sitka Spruce
Top Thickness: Standard
Bracing Material, Top: Spruce
Bracing Pattern, Top: X Brace
Bracing Pattern Number, Top: 3-D Super D
Bracing Shape, Top: Scalloped
Bracing Style, Top: Golden Era
Back and Sides Material: Sinker Mahogany
Wedge Material: Sinker Mahogany
Bracing Pattern: Super D
Neck Taper: High Performance Taper
Neck Profile: GE Modified Low Oval
Headplate Material: Sinker Mahogany
Headplate Inlay: Alternate Torch
Headplate Inlay Pearl Species: Select Abalone
Fingerboard Material: Black Ebony
Fingerboard Material Grade: 2
Fingerboard Stain: No
Fingerboard Oil: Yes
Fingerboard Radius: 16''
Fingerboard Width at Nut: 1 3/4"
Fingerboard Width at 12th Fret: 2 1/8"
String Spacing: 2 5/32''
Fingerboard Length: 17.984''
Fingerboard Thickness: Authentic Thickness
Fret Wire: Standard
Satin Finish Package: Akzo Satin Lacquer
Tuning Machines: Grover Nickel V97-18NA StaTite 18:1 Vintage Button
Case: 3-Ply Hardshell with Domed Top