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Alternating mains

Q: A friend begins the mains at the center as recommended by USRSA, installing three mains on the right, three more mains on the left, and then three more on the left, before going back to the right side. In other words, he is tensioning six mains in a row. Is this just a matter of personal preference? Is it safe, or does it inflict more stress to the frame?

A: The whole reason behind alternating mains is to balance the not-inconsiderable stresses on the frame at its most vulnerable time. Installing six mains in a row means there are that many freshly-tensioned mains on one side of the frame, while the three mains on the other side of the frame have lost tension and are therefore exerting less force. Modern frames are pretty strong, and your friend may never run into a problem doing the mains this way, but the stresses could be better balanced, which may enhance frame longevity, as well as produce a more consistent stringbed response.

From the April 2007 issue
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