C. F. Martin Jr. builds the first addition to the North Street factory known at "The Barn." The industrial revolution was in full swing and he introduced steam-driven machinery, including band saws and sanders, facilitating increased production with better, more consistent quality guitars, further positioning the company for future growth.

In 1867, C. F. Martin, Jr. and his cousin Christian Frederick Hartman became partners in the Martin Guitar Co. The exact date of the dissolution of this partnership is unknown, but when C. F. Jr. died on November 15, 1888, Hartmann was again only an employee and the company was passed to Frank Henry Martin and his mother.

It is unfortunate that not more is known about C. F. Martin, Jr. Although little changed at the Martin Guitar Company under his leadership but further standardization of guitar models, his son would see the family company through its greatest period of change and growth.

In 1894, Frank Henry Martin's first son, Christian Frederick Martin III was born, followed in 1895 by a second son, Herbert Keller Martin.  Besides a wife and two young children, Frank Henry was also responsible for supporting his mother, who was still co-owner of the company, and two unmarried sisters. That’s a lot of mouths to feed when your company’s sales are stagnant.

To compete with mandolins and banjos, Frank Henry Martin introduces the 12-fret 000 size of guitars, the biggest Martins so far. The first Style 45 guitars, 12-fret 00 45s, are designed featuring a pearl-trimmed body, a pearl “vine” inlaid fingerboard, and pearl inlaid pickguard similar to bowl mandolins of the period. Frank Henry is pictured (left with tophat) with his two sons: C. F. Martin III (center) and Herbert Keller Martin (right).

Frank Henry Martin (center wearing vest) with his employees circa 1910. Far right is C. F. Martin III. Far left is Herbert Keller Martin. At this point in the evolution of the company, each of the workers had developed a craftsmanship specialty.

While the first full-sized D-45 was years away from production, Martin built four “Baby D-45s” (or the “1-45” as it was dubbed) on special order for the Oliver Ditson Company. These guitars closely approximated Martin’s standard “1” size but with wider sides, 45-style pearl binding, and slotted peghead with a “torch” inlay.

Martin uke production takes off. The Company continues to design and build for Oliver Ditson Co. of Boston, Philadelphia and New York, including the first full-size “Dreadnought” guitar named after a class of large British battleships. The large size was to provide bass for vocal accompaniment, as well as for greater volume. These original Ditson Dreadnoughts were fan braced, had 12-fret necks with slotted peghead, and most were designed for Hawaiian slide style of playing.

C. F. Martin III, the first Martin to attend college, graduates from Princeton. He continues to work alongside father and younger brother in the family business.

Martin steel-string Hawaiian guitars are formally introduced as lap style models, played with a steel bar. Martin Hawaiian guitar sales soar.

Martin discontinues use of elephant ivory in bridges and bindings, instead using ivory-colored celluloid ("Ivoroid") for bindings and ebony for bridges.

Frank Henry Martin hand crafts a scroll cut wooden plaque in one of the Company’s workrooms inscribed with the Latin phrase "Non Multa Sed Multum" which summarizes the family’s guitar-making philosophy: "Not Many, But Much" or "Quality Not Quantity."

Although Martin didn’t make any mention of building guitars for steel strings until the early 1920s, a few were made on special order starting as early as 1900. About a dozen 0 and 00 models made for steel strings show up in the sales ledgers covering the first decade of the new century, and all were Style 21 and higher, including some pearl-bordered models. The real push for steel strings, however, came in the late ‘teens, and by then it was the less-expensive mahogany models that were given the new stringing.

Southern California Music, which was actually a small chain of stores stretching from Pasadena to San Diego, may not have been as big as Ditson, but being closest to the center of the Hawaiian music hurricane they too wanted their own line of instruments. They supplied Martin with koa wood from the islands for guitars that would be more authentic for Hawaiian music. These all-koa instruments, introduced in 1916, would be Martin’s first production guitars made exclusively for steel strings. Once again, the earliest versions had no markings as to their origin. Impressed by the number sold, Martin cautiously introduced its own line of all-koa guitars a year later. Still apparently unsure of the steel-string guitar market, however, these koa models didn’t appear in the company’s catalogs until 1922. One possible reason for this long delay is that there was considerable friction between lovers of what was considered the true guitar, strung with gut, and newcomers to guitar who wanted to forego years of studious practice and just have fun playing pop songs on steel strings. Instead of risking offense to the gut-string faithful, Martin pitched it’s new all-koa models directly to dealers and let them take it from there.

Martin begins production of tenor banjos. Never cataloged, only 96 will be built until discontinued in 1926. Martin will later build Vega banjos, in Nazareth, in the early 1970s for several years. Over the years, Martin has made a variety of stringed instruments including zithers, harp guitars, tiples, taropatches, bandurrias, bowl and flat-back mandolins, ukuleles, an 8-string “Octa-Chorda” (now in the Martin museum), tenor guitars and archtop guitars.

Martin modifies the 000 (or "OM" Orchestra Model) to accommodate 14 frets clear of the body, instead of 12, for star banjo player Perry Bechtel who wants to switch from the long-necked plectrum banjo to the guitar. Later named the OM-28, it is the first regular Martin guitar specifically designed for steel strings, and it proves so popular that other guitar makers copy it. It soon becomes the industry standard.