| The hardware required is generally the following: A track along the deck
so that the block position can be adjusted easily. A block on the track.
A winch. (The same on the other side of the boat). And, especially on
larger boats, a turning block aft of the winch so that the sheet leads
onto the winch nicely. The track can be omitted, but the chances of
getting a fixed_in_place block in the right place are small, and the
correct position does vary with wind strength and sea conditions (if you
are lusting for that last 0.1 knot).
There are at least five ways to choose the 'right' genoa hardware:
1. Look at what the other person is using on his/her identical or
similar boat. Ask if he/she finds it adequate.
2. Intuition: Does the hardware look strong enough? This is not likely
to result in the optimum hardware. Genoa loads can be higher than you
might think. Or, if your intuition goes the other way, you may get gear
far stronger than you need.
3. Call the boat's builder and get his recommendation. Trouble is, many
builders pay more attention to cost than adequate strength and ease of
use. Based on my not vast experience, 90% of the builder installed
winches are at least one size too small. The rest of the builder
recommended gear is probably at least marginally safe, thanks to product
liability suits.
4. Use a winch manufacturer's recommendation for winch size. Choose the
rest of the gear to have a comparable strength. Barient's winch sizes,
for example, are the safe working load on the winch in hundreds of
pounds. My Barient 27s thus have a safe load of 2700 pounds. My turning
blocks are rated at 5000 pounds working load. The track is rated at 3950
pounds and the track blocks at 2800 pounds. In a brisk breeze I suspect
that none of this is any too strong (315 sq foot jib in 30+ knots) and I
can only with considerable effort trim the jib in. My winches are one
size larger than builder recommended and are a size Barient recommends
for racing. Some of the block manufacturers (eg Scheafer, my favorite)
make recommendations based on sail size and/or boat size.
5. Calculate the likely loads and choose the gear accordingly. There was
an article in Cruising World or Sail some time ago telling how to do
this. A bit technical unless you remember geometry. (I can send a copy
to anyone who desperately wants one.)
Above all, remember, if it breaks, someone could be very badly hurt. So
err on the side of too strong.
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| The safest way to go is to call a reputable sailmaker. He/She works
with these problems every day and can specify the correct hardware,
track placement and the like. In the Boston area, this is easy as
there are lots of 'world class' sailmakers around. in other parts of
the country, contact a service loft for one of the national firms, or
find a reagonal or local loft. There are more out there than most think.
As one who was aboard a PJ/Frers 53 when a turning block exploded,
these things can kill! don't try to eyeball it. Lofts will gladly
make recomendations on this sort of thing as a goodwill gesture.
Happy (and safe) sailing
Tom Tyson
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