Mitre Cut?

how many of you have been around long enough to remember those? Quantum
San Diego’s
Keith Lorence tackles this one.

Q: When
I look at sail lofts and their offerings they split between cruising and
racing and some times performance cruising. When it comes to cruising
the options seems to be Dacron and crosscut. Only one sail loft advertises
mitre cut. Question: Is there an advantage to mitre cut genoas as one
of the lofts claim? Can Dacron be used to make tri-radial sails or is
the only option fro tri-radial some kind of composite?


S/V Tangerine
C&C 35 MK II

A: Most all sail lofts offer both racing and cruising sails. There are some
lofts that offer only cruising sails largely due to the highly specialized
nature and complex construction of racing sails. Those lofts prefer to
stick with the tried and true Dacron sails and often build them using
conventional (cross cut) construction. This fits with many traditionalists,
and there is a niche for these sails for those sailors.

Again, the vast majority of lofts will make both. There are many fine
fabrics to choose from, beginning with Dacron, (very durable and a standard
of the industry) to Spectra laminates, and a whole bunch in between. Some
cruising laminates use Vectran as the primary fiber and, like Spectra
laminates, are tri-radial in construction. Laminated sails are generally
a slight bit lighter and because of the higher modulus of the fiber, they
stretch less. They generally do not last as long as a Dacron sail, but
have longer performance life span. They are however prone to Mildew and
should be taken down when not in use for long periods.

As for Mitre cut sails, that was a fashion prior to the 70’s as Dacron,
and it’s predecessors Rayon and Nylon, were very stretchy and aligning
the panels along the stronger fill angle reduced stretch by taking advantage
of the fill yarns. These days, fabrics are far more stable, (through calendaring
and finishing), and the need for the mitre cut has gone away.
Dacron as a radial cut sail is generally inefficient due to the inherent
weaving issues. It is simply not possible to achieve a strong warp in
a Dacron sail. We tried it in the 80’s with a little success, but not
enough to overcome the added labor
At the end of the day, a crosscut Dacron sail made of quality fabric is
a great option for cruising, next in line is a radial sail made from one
of the laminates.Many choices, and you are best advised to talk to one
of the quality sailmakers in your area for some advise. Let us know what
you come up with!