...but not every crochet-crazed scrapbooker knows his or her way around a 3000-pound Heidelberg Windmill. In fact, most craft geeks have probably never heard the name of the giant machine that produces most of the textured, old-timey graphics that adorn the greeting cards and wedding invitations so beloved by the hipster set. I certainly hadn't.

But with my letterpress card collection overwhelming my sock drawer, the time seemed right to learn the process behind these products. I called up the crew at San Francisco's own Hello! Lucky letterpress shop and design studio to see if they'd show me the ropes. They agreed.

These days, most people only bother with snail mail for truly meaningful correspondences, so it makes sense that two people in a deep relationship founded a company specializing in the handmade and handwritten. Sister duo Eunice James and Sabrina Moyle run Hello! Lucky together—Eunice handling creative direction and Sabrina holding down the business side. In the years since they began, both sisters have gotten married and started families, making them well-poised to guide clients through these momentous events.

Hello! Lucky's two-story facility sits on a nondescript block of SOMA. From the street, one would never guess there's an imagination factory hidden inside. Upstairs, the design and sales teams post up at computers, surrounded by paper of all colors, drafts of custom cards, and inspirational tchotchkes. Downstairs, apron-clad printermakers tattoo words and illustrations onto thick paper cranked through presses from the 1950s. The work soundtrack for the company's fifteen employees is a percussive rhythm of pneumatic machines breathing and stamping their way through bottomless stacks of cards.

Sabrina sits me down at a big dining table in a spindle back chair that looks handed down from somebody's grandmother. This is where Hello! Lucky's designers consult with engaged couples, expectant parents, and party hosts when they come to start planning their events. Corkboards and shelving units feature inspiring examples of past designs, ranging from the quaintly conservative to the charmingly zany.

Hello! Lucky's aesthetic is distinctly vintage, and, Sabrina explains, because the letterpress process constrains color variety, most samples have a pared-down palette. In recent years they've expanded into digital printing, allowing more colors and detail while maintaining the handmade look.

Sabrina escorts me downstairs to the presses, where she hands me off to printman James Tucker, who, along with his printing team, take all of Hello! Lucky's designs from digital drawing to finished product. The only piece of the process Hello! Lucky conducts offsite is the transfer of their illustration to film—the intermediate stage between design and printing. A photo processing facility in the Dogpatch neighborhood turns the digital file into a high-contrast photonegative and sends it back to the Hello! Lucky studio.

James shows me the film negative for a wedding invitation he's working on. Next to it, on a printed invite, it's easy to see how the transparent lines on the negative become the embossed lettering on the card. To get from point A to point B, you have to transfer the photo to a polymer printing plate. James demonstrates by cutting a piece of photosensitive plastic the color of a prescription pill bottle into a rectangle the same size as the film.

We carry it to a set of slim metal drawers with a temperature dial and several gauges at the top and, after adjusting the temperature, James slides the plastic piece into a narrow drawer that emits the purple glow of ultraviolet light. The film and plastic spend 45 minutes in their tanning bed and, like a pale Northwesterner in the dead of winter, emerge transformed.

After exposure, we remove the plate from its drawer and separate the film from the plastic. The UV rays have transferred the negative image onto the plate—in this case a block of embellished text—and hardened all of the lines in place. We then place the plate into another drawer filled with a shallow pool of murky water and lined at the bottom with brushes. The plate is affixed to a rotating mechanism that jostles it against the brushes under the water, sweeping away unexposed polymers to reveal a raised, stampable design that's ready for the press.

The photopolymer plate technique is one of the major supporting factors in the resurgence of letterpress as 21st century craft. James shows me several carved copper blocks—vestiges of older techniques—that, while impressively intricate and beautiful, are clearly a much more labor intensive, and thus costly, approach. Some studios print images directly from computers onto plates but at Hello! Lucky they still use the UV strategy. "It's not as fast," James explains, "but it's more tactile."

Once the plate's been made, the real fun begins. Hello! Lucky houses three Heidelberg Windmills, a Heidelberg Cylinder, and a Vandercook flatbed press. The Windmill—so named for the formation of the paper-feeding and delivery arms of the machine—operates with an electric motor that keeps printing consistent in both speed and pressure. When Sabrina and Eunice launched the company, they purchased a Windmill on eBay for a few thousand dollars (and at least as much in shipping), and set it up in a garage. With some of the old machines, safety is a gamble—Eunice smashed her hand in one while manually feeding paper—but the studio's current suite all have protective components to keep everyone's extremities intact.

James shows me how to secure a plate into one of the machines and prep the paper for printing. A stack of paper sits on a ledge of the machine and a pair of heavy mechanical arms grab a piece at a time, dropping it into the press where the plate is pressed firmly against it, then grabbing it and delivering it onto a stack of finished cards.

Each piece must be run through the machine as many times as there are colors in the design, and the ink rollers must be thoroughly cleaned in between each run—hence the limited number of colors on most true letterpress cards. The invitation we're working with is a single-color piece, requiring fewer passes through the machine, and therefore less time and a lower cost.

These days, Hello! Lucky often employs a hybrid of digital and manual techniques, which increases the options for clients in terms of both creativity and price. Although the deep impression generated by old-school presses is not as distinct with digital printing, advanced technology makes it possible to achieve a good looking product, and to include things like color photos of babies and couples—a painstaking and cost-prohibitive process without the computer.

The relatively simple sample we're working with goes through the press in no time, but flourishes can be added down the line, like intricate paper linings for the envelopes and personalized mailing addresses printed directly onto RSVP cards (a digital feature). When all of these details are finalized, Hello! Lucky's job is finished, but the personality they've infused into each custom product carries through until the celebrating is done. And unlike the vanishing Evite, these are the kinds of crafts that inspire even the most electronically-addicted of us to grab an old shoebox and start saving for posterity.

Getting hitched? Bun in the oven? Contact the Hello! Lucky team to start planning your own custom letterpress for the exciting events in your future. For ready-to-send paper goods, you can find Hello! Lucky's cards at shops throughout the city, including Rare Device on Market Street, Kinokuniya Stationery in Japantown, Xapno on Haight, and dozens of others. If you'd like to try your hand at crafting your own, check out the class schedule at The San Francisco Center for the Book. And if you already fancy yourself a pro and just need the equipment, you can buy small presses for home use on eBay and other online retail and auction sites. Just brace yourself for the cost of shipping.

Photos by Anna Hurley.