Skip Gundlach wrote:
So, we're floating, again, and letting the hull settle into its water
configuration, having been out for more that 2.5 years, before we start
tweaking.
Hmm, when you say "settle into the water," what do you mean?
For the planks to swell & close up the seams? A fiberglass
boat should have exactly zero "settling" to do.
I want to tune the rig before we start sailing, and currently all the
shrouds and intermediates save one seem very loose by hand.
Regardless, they're probably not set correctly.
Ya think
If they're loose to the hand, then they are definitely not
set up to sail. But it's easy to do a basic set-up
Once the hull's settled in, I expect that a Loos gauge is the way to go
to see the right setup. I have two questions:
First, is it worth the investment to buy one? I'm not a racer, nor
will I ever be.
Personally, I don't think that matters. If you want to be
able to set up your rig (or a friend's) properly *and*
(here's the key part) be able to do it the same every time,
then a Loos gauge is the best tool for it. There are other
ways of judging tension, in fact you can home-brew a tension
gage. But it will cost more in time and be less accurate.
OTOH you can borrow one, or jury-rig a tension gauge that's
good enough.
... But I expect that a properly tuned rig will be kinder
to the boat, in any event. Is this something which I'd use frequently
or something better done by paying a rigger (the largest tool is what
our boat needs - it's 180 at list) on the occasions when I thought I
needed it?
Depends partly on your rig & partly on your goals. It's
probably cheaper to pay a rigger, especially if you have
multiple spreaders.
Second, how does one determine the proper tension for a given boat and
the given stays/shrouds? Or, is that covered in the manual which comes
with the tool?
"Proper tension" depends on who you ask. The minimum should
be 10% of the wire's limit (termed "working load").
Setting up a cruiser's mast should be quite simple. The goal
is to get the mast standing up & keep it there! It's
surprising how few people pay any attention to this.
http://www.sailingsource.com/neilpry...al/rigtune.htm
http://hallspars.com/Resources/Articles/rigtune.htm
Start off with all standing rigging slightly loose to the
hand. Use either a plumb bob (which I don't like, since it
can be misleading) or a protractor from 'way back on shore
to measure the RAKE of the mast. This is how much it leans
aft. You want enough to get a good helm balance when the
boat is powered up under sail. Too much weather helm means
too much rake (ie leaned too far aft). This is adjusted at
the forestay (looser = more rake).
Now get the mast straight up & down athwartship. You'd be
amazed how many boats are sailing around with their mast
leaning to one side or the other. The lower shrouds should
be loose, uppers barely taut. Put a tape measure on the main
halyard and make a measurement to a good marking point which
can be definitely the same on both sides, say for example to
the gun'l right at the chainplates. It almost certainly
won't be the same on both sides unless you are very lucky.
Adjust only the upper shrouds until it is the same on both
sides, then tighten the upper shrouds to the minimum,
counting the turns on each turnbuckle & keeping them the
same, then lock them.
Now, sight up the mast track. It should be perfectly
straight all the way up. If not, tighten the lower on the
side that it bends away from.
When the mast is raked properly, centered, and straight
(termed "in column"); and all the shrouds are set up to
their minimum tension, you can go sailing. You will want to
tighten the uppers enough to keep the lee shrouds from going
slack (assuming your hull is strong & rigid enough), and the
lowers enough to keep it in column. You will also want to
adjust the lowers such that when you tighten the backstay,
you get a little curve aft in the mast. This does two
things, it controls sail shape and it prevents the mast from
pumping (alternately bowing one way then the other as the
boat goes over waves). Remember to always adjust the shrouds
in pairs, keeping the same number of turns on each side.
And don't overdo it, remember the mast & rig is like an
enormous bow & arrow that you do *not* want to shoot!
And that's it. Many fairly successful racers do less.
Fresh Breezes- Doug King