The table had been set. Well, nearly. Stephen Coles, a tall man with a beard and a passion for the typographical, was still adjusting the pieces. He repositioned a thick book that looked very heavy and very old (and was, in fact, both). He fanned out bits of ephemera, then stacked them. He subtracted items and added others, then stood back, considered his work and adjusted again.

To “set the table” at the Letterform Archive is an art, a subjective exercise in revealing, through a few dozen pieces, a collection of 50,000 typographical artifacts. “Everybody who is at the archive,” he said, “does a different version of this because we all have different backgrounds.”

On this occasion, Coles, the archive’s associate curator and editorial director, had decided to approach the task from a roughly chronological standpoint. So, at the head of the table was a Sumerian cuneiform tablet (stone, 2 by 2 inches, approximately 4,000 years old). From there, one went to an early letterpress printing of the Nuremberg Chronicle that describes, in great detail, the history of the world up through the late 1400s. After that was a 1450 manuscript, drawn by hand, that was placed next to a copy of itself, one that had been made with a press.

Coles’ table was set with Black Panther protest art, with an original copy of the now-famous NASA Graphics Standards Manual, with stacks of paper that showed the evolution of an early computer font. Together, the pieces become an art show — a gallery wall laid flat on a warm, wooden table.

All of these items were connected in that they “related to the history of communication, writing, typography,” said Coles. And that, in short, is why the Letterform Archive, a place tucked away in a nondescript apartment building in San Francisco’s Dogpatch neighborhood, is so unique. Its collection of 50,000 items represents one of the largest and most obsessive of its kind. This archive stares intently at a narrow subject, revealing a sprawling world. It is also a place that changes lives.

The archive began, some five years back, out of simple necessity.

The founder, Rob Saunders, had worked as a designer, teacher, publisher and consultant and during that time, 40 long years, he put together a typographical collection about 15,000 pieces strong. Then he reached a point where he thought he ought to figure out what to do with it all.

He made some calls to universities and to museums. They were interested, but he was nervous. “It just seemed like it would go into a black hole, and it wouldn’t be very accessible,” he said. There’s not much use in a collection that nobody knows exists.

At the same time, his home had begun to welcome a steady stream of visitors. Tânia Raposo, a recent type design graduate, who was interning for him and helping organize the collection for an eventual donation would bring her friends by — lots of young designers, fresh from school — to see, in person, what they had only ever seen in books or on screens, to hold the pages and the objects in their hands and feel their textures and their weight.

That’s how Coles found the archive. “One day he invited me over, and I was just amazed … it was such a deep collection,” he said. “Seeing it in person was a huge, life-changing moment for me.”

“They were seeing these things for the first time, even if they knew about it,” Saunders said. “It was just a lot of fun, and what I realized is that there was an underserved public, that there was a passionate interest in this stuff.”

So he did the only thing there was to do: He gave his home over to the collection. “It was easier moving myself,” he said. And that meant the archive could feel like a home of sorts for its visitors, that the collection would be seen and touched and used in a place that felt comfortable.

The archive opened to the public in 2015, and very quickly it more than tripled through acquisitions and donated collections, including one from Emigre, an Oakland type foundry. Smaller donations come in, too, said Amelia Grounds, the archive’s librarian. There are, for instance, “the people who went on vacation to Japan and brought back a piece of ephemera and said I thought might like this because it has Japanese letterforms on it.”

As the collection grew, so did the actual archive. It now spreads throughout not just Saunders’ old home, but also two other units in the building. The shelves are crowded and sometimes messy, a temporary truth because there is so much intake to process.

The archive is organized in an evolving language. There are sections like “Marks and Symbols,” “Sign Lettering,” “Type Design,” “Concrete Poetry” and “Street Art & Graffiti.” Grounds and another librarian have had to create this taxonomy, because a collection like this has never really existed. She is also working to translate this all to the web, to make a visual collection searchable with images and few words.

The sorts of people who come to the archive vary — there are the library tourists, the tech designers, the students and the curious, all by appointment only. Their first experience is always in the Reading Room with its vast wooden table set just for them. Sometimes they return with a specific request — “the color blue,” “cheerful fonts,” “airplanes” — and the archive obliges. I’m coming to you, they say, because I can’t find this anywhere else.

Letterform Archive is many things beyond its collection of design artifacts. It is also a school for students interested in learning font design. It is a publisher of books. And it is, on many evenings, a community salon. But at its core, it is a testimonial to obsession.

On a recent afternoon, Saunders, sitting near a fresh-set table, explained the real beginning of the archive.

“I had a tutor that learned italic handwriting and thought it was cool,” he said. “I started doing it. And I was kind of a juvenile delinquent, and it pulled me out of it.”

“I never knew that,” Coles said.

“You knew that.”

“I never knew you were a delinquent.”

“Well, OK, I never went to juvie, but I was kicked out of three high schools. I was somewhere in between.”

A quiet moment, and then Saunders says: “Anything you dive into and become obsessed with can change your life.”

Letterform Archive: 10 a.m.-6 p.m., Monday through Friday, by appointment only. 415-802-7485. 1001 Mariposa St., #307, S.F. letterformarchive.org