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Seven Cycles - Watertown MA - November 2011

click here for slide show
Seven Cycles and Ciclismo Classico combined to put on a great party at the former's facility in Watertown MA. A group of 50 or so cycling enthusiasts (one must assume) gathered in an inviting Seven showroom surrounded by beautiful bicycles, tasty food, and a bar serving beer and wine. The program consisted of Ciclismo talking us through a photo-enhanced description of the international bike tours that they so carefully craft and Seven walking us through a factory tour.

Being a sucker for factory tours, I took notes along the way. Seven asked us not to take any photographs within the manufacturing facility, referring us instead to an online article in Embrocation Magazine from which I've gratefully lifted the photos below and in the accompanying slide show.

Much in the same way that a Saville Row customer commissions a suit designed to his or her exact specification, a Seven client is not simply selecting a bicycle from the rack. In fact, building to order as they do, Seven has no racks at all, unless you count the ones on which they store their raw tubes of steel and titanium (Seven steers clear of aluminum for reasons they didn't explain; the starting form of their carbon fiber frames was lost on me).

Fun fact 1: bicycle frames are ideal applications of titanium for its light weight, tunability, and durability [1].

Fun fact 2: titanium is the Earth's 4th most abundant metallic element, trailing only aluminum, magnesium, and iron [1]. (That said, those without a reasonably technical background may be challenged to name more than one or two other metals.)

Fun fact 3: titanium, and therefore titanium tubes (at as much as almost $60 per foot), are expensive because of the cost of extracting the metal from other compounds such as rutile ore and ilmenite [1].
The Seven journey begins at an authorized local bike shop. The cyclist isn't limited (except perhaps by availability of funds--prices start at $3,500 for the Halcyon touring bike and climb north of $16,000 for the Axiom tandem [2]), as options include road, tri, mountain, cross, and touring.

Fun fact 4: titanium appears to have made its bicyle debut on a Merlin mountain bike in 1987 (Seven's founder and many of its employees came from Merlin) [1].
Working with Seven, the customer fills out a detailed survey before proceeding to a short 10-15 minute interview and a more involved body measurement. The phrasing of one particular step in the measurement process isn't one that you encounter every day: "[H]old a book with a 1 1/2 inch binding so the binding is pressed hard against your crotch--like a saddle--and the bottom of the book is against the wall [3]."

The LBS then sets up the customer's existing bike (or one provided by the shop) to the carefully arrived at specifications that Seven plans to build, giving the customer the opportunity to take the intended sizing out for a spin. With optional guidance from Seven, the customer creates a custom paint/finishing design and then signs off to release the project to the 2-5 week production sequence [4]. Our tour featured titanium frames in various stages of completion--clearly, the process would vary in small and large ways depending on the material of the frame being constructed.

Matt O. took us through the machining step that kicks off manufacturing. Based on a CAD drawing, tubes are carefully measured, cut, and machined in dedicated fixtures. We learned that the facility produces 25-30 frames this time of year, with a team of employees juggling various tasks except during a Wednesday clean-up window. Within some general constraints, employees are able to choose which 8 hours to work during the 12-hour workday.

Mike S. took the handoff from Matt to tell us about welding. Titanium is more particular than other materials, but the general rule applies: clean tubes lead to clean welds (in this case, tungsten inert gas, or TIG). Tack welds are applied to temporarily hold the tubes in close to final position. TIG welding of titanium requires an argon purge inside the tubes as well as on the outside at the weld zone. A fixture is used for precise near-final alignment, after which the full welds are made. Special skill is necessary, as the heat introduced during the welding process slighly alters the alignment into the finished configuration, hence the fixturing only to near-final positioning.

Matt S. saw us next to explain final machining, which includes bottom bracket boring and threading, head set boring and threading, and alignment checking. A carbon seat tube insert is added to avoid a metal-metal interface. The frame is buffed, as 85% of titanium frames don't receive paint. For those unpainted frames, decals and components are added. Pledge (yes, the furniture polish) is used to create a waxy finishing coat.

Karl B. completed the tour with a discussion of paint. Overall, about half of their frames are painted (colors include elecric blueberry and amber ale [4]), first with a prime and then a finish coat. Titanium is not porous, and therefore not very accepting of paint, but a special primer solves that issue. A drying step completes the manufacturing process prior to the installation of components.

The blending of art and science complete, delivery to the customer marks the end of one journey and the beginning of many others.


[1] "Seven's Titanium Technology & Manufacturing Technology," Seven Cycles, Watertown MA.
[2] "2011 Pricing Guide," Seven Cycles, Watertown MA.
[3] "Seven Cycles Custom Kit," Seven Cycles, Watertown MA.
[4] "Seven Cycles 2011 brochure," Seven Cycles, Watertown MA.