Monday, February 3, 2014

Winter Wheelset Part One: Studding Tires

My interest in amateur wheel building actually stemmed from a modest attempt at retrofitting a clunky, too-small mountain bike as an All-American winter beater on a budget. Naturally, I came to see spending a hundred bucks on carbide studded tires at my LBS as a breach of my liberties, and so I set out to drive pan-headed sheet metal screws through my Continental Travel Contacts (rather ironically, the newest componentry of the poor old MTB).

A few rules of thumb present for studding tires. One mustn't use screws too lengthy, but they of course must be long enough to protrude from the treads--perhaps by half a centimeter. There ought be more studs on the front wheel than the rear, where load and therefore friction wane. The patterning of the studs must repeat periodically such that a full revolution of the pattern around the wheel ends where it began. 

The resolution of these simple considerations will depend on the tread pattern of a particular tire. Have a gander at my solution, which employs 44 and 88 studs on the rear and front wheels, respectively:

Studding patterns are shown for the rear wheel (44 studs) 
and front wheel (88 studs) [click to enlarge]

The treading followed an ABBABB pattern on each side of each tire, with A being a slightly larger polygon-shaped tread than B. The front wheel was studded (as indicated with red text) as ABBABBABBABB, and the rear wheel likewise as ABBABBABBABB. Thus, twice as many studs were used to complete the pattern around the front wheel. Given the option, use treads at the tire's edge to prevent undue rolling resistance.

As it happens, the local hardware store didn't stock the 1/4 inch pan-heads I originally sought, but having gone with 3/8 inch, I am glad in retrospect. The protrusion is more than one would expect from a typical manufactured studded tire, but as they wear down a bit and recess back into the treads, I expect they will maintain their bite quite nicely.



After settling on patterning and count, but before screwing each stud in by hand, holes were drilled through the appropriate treads against a slab of wood to catch the drill bit. This is vital for uniform stud orientation and can be tiring on the hands, depending on the rigidity of the tire. I suggest taking breaks working through this prep work. Better to prolong the process than sully your hard work with a poorly drilled pilot hole.

Finally, the inner tube must be shielded from the screw heads inside the tire. Tire liner may be acquired for flat prevention in a more general sense, but I found the liner too thin and narrow to adequately cover the screw heads. I widened it with Gorilla brand tape to accommodate the spacing.


Tuffy Tire Liner was reinforced and widened with Gorilla Tape
Having commuted for the last month or so with my homemade studded tires, I am quite happy with the results. So far there is little sign of wear (a worry when foregoing carbide studs), and I've yet to have a real fall. The unbearable rolling resistance I anticipated is not nearly as bad as one might expect.

Up next: I attempt to stripe my spokes red and white to compliment the spangled banner that is my steel, blue MTB frame. The results are a mix of shitty craftsmanship and rugged individualism.

-WGM

"Seriousness, young man, is an accident of time. It consists, I don't mind telling you in confidence, in putting too high a value on time. I, too, once put too high a value on time. For that reason, I wished to be a hundred years old. In eternity, however, there is no time, you see. Eternity is a mere moment, just long enough for a joke."

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