[Rhodes22-list] Standing Rigging and Tension

Mark Kaynor mark@kaynor.org
Thu, 24 Oct 2002 13:11:43 -0400


Roger,

I put it into the document library in MS Word format.

Mark

----- Original Message -----
From: "Roger Pihlaja" <cen09402@centurytel.net>
To: "The Rhodes 22 mail list" <rhodes22-list@rhodes22.org>
Sent: Thursday, October 24, 2002 7:48 AM
Subject: Re: [Rhodes22-list] Standing Rigging and Tension


> Al & Michelle,
>
> Enclosed is a copy of my rig tuning procedure.  I was kind of hoping this
> procedure would have made onto the FAQ web site by now, but I guess that
> didn't happen.  The standard Loo's tension gauge will do just fine for
your
> purposes.  Enjoy!
>
> Roger Pihlaja
> S/V Dynamic Equilibrium
>
> ______________________________________________________________________
>
>                        Rig Tuning Procedure For Rhodes 22
>
> The 1st thing you want to do is measure the length of the forestay on
center
> from pin-to-pin.  On my 1976, standard mainsail, Rhodes 22, this
measurement
> is 333-5/8 inches.  Write this number down because it is very important.
> If your forestay length is more than a couple of inches different than
this,
> you might want to reset it to 333-5/8 inches as a reasonable starting
point.
>
> Now step the mast.  Take the excess slack out of the forestay & backstays
> with the backstay adjuster.  You don't want things real tight at this
point.
> All upper & lower sidestays should be slack.  Go to the base of the mast,
> pull a halyard taut along the mast & sight up the mast from the rear &
from
> the side.  Any deviation from a straight mast will show up as a gap
between
> the mast & the halyard.  There should be no observable bend or bowing in
the
> mast.  If there is, the mast may have been dropped & bent at some point or
> may have some other problem.  You should call Stan at GBI & he will be
able
> to help you work out your problem.
>
> I like to use a Loo's tension gage.  The model 91 is the appropriate range
> for the Rhodes 22.  Remember to always measure the tension at the same
> relative position on each shroud every time.  On Dynamic Equilibrium, I
> have marked these measurement points with little spots of paint on the
> wire right at my eye level.
>
> The upper sidestays are adjusted next.  Raise a tape measure up the mast
on
> a halyard.  Measure to the same point on each side of the boat.  I like to
> use the edge of the toerail right next to the sidestay.  Tighten the
> turnbuckles a little at a time on each side to adjust the upper sidestays
> until both sides are the same length +/- 1/4" & tensioned to approximately
> 300 lbs +/- 5%.  This procedure assures the top of the mast is centered in
> the boat & the upper sidestays are tensioned equally port & starboard.
>
> What you do next depends upon whether your boat has the IMF mainsail or a
> conventional mainsail.
>
> On an IMF mainsail boat, I would adjust the 4 lower sidestays so they were
> all approximately the same tension.  I would start with approximately 200
> lbs +/- 5% on all 4 lowers.  This is not a lot of shroud tension.  Check
for
> mast straightness with the halyard again.  You want the mast to be
straight
> in order for the IMF furling mechanism inside of it to be able to turn
> without binding &/or excessive wear on the bearings.  Minor bending or
> bowing can be taken out with the lower sidestays.  However, I would call
> Stan at GBI if I couldn't get the mast to straighten out with a difference
> of about +/- 15% on lower sidestay tension.
>
> My Rhodes 22 has a conventional mainsail.  I have a very roachy fully
> battened mainsail which has been cut to respond to mast bend.  I have my
> backstay adjuster set-up to adjust quickly from the cockpit with
calibration
> marks on the line.
>
> Tighten the turnbuckles equally & a little a time on each side to keep
> things reasonably centered.  I adjust the forward lower sidestays to 400
lbs
> +/- 5% of tension, and the aft lower sidestays to 200 lbs +/- 5% of
tension.
> Then, check for mast straightness with the halyard.  Believe it or not,
the
> standard mast on the Rhodes 22 is such a stiff telephone pole that, at 200
> lbs differential tension on the lowers, there will be a barely detectable
> fore/aft bend in the mast with no sails set & the backstay adjuster slack.
> At 400 lbs of tension on the lower forward sidestays, when the backstay
> adjuster is tensioned, primarily only the upper half of the mast is pulled
> towards the stern.  The forestay is tightened & the mast is bent at the
same
> time.  Both actions are exactly what you want to obtain proper sail shape
in
> a high wind situation.
>
> Now go out sailing.  On a close hauled course, put up enough sail to heel
> the boat over about 15-20 deg.  Make certain the rudder blade &
centerboard
> are all the way down.  On my Rhodes 22, the above tension settings cause
the
> mast to remain straight & more or less centered in the boat.  The primary
> thing to check is the upper sidestays.  On my Rhodes 22 with the above
> unloaded tension settings, at 15-20 deg of heel, the windward upper
sidestay
> should have about 450 lbs tension & the leeward upper sidestay should have
> about 150 lbs of tension.  I have my upper sidestays set-up such that the
> leeward upper sidestay tension drops to 0 lbs at about 30 degrees of heel.
> At this point, the windward upper sidestay will be under about 600 lbs
> tension.  Note, normally the stays are set-up to give proper shroud
tension
> & the correct amount of weather helm with full sail set.  This tends to
> limit the weather window in which you can do this sort of tuning.
>
> When all sails are properly trimmed & the boat is "in the groove", there
> should only a slight amount of weather helm.  If there is a huge weather
> helm, or neutral, or lee helm; then, you need to adjust the rake angle of
> the mast.  If you have neutral or lee helm; then increase the forestay
> length.  To get rid of excessive weather helm, shorten the forestay.  The
> balance of the boat is very sensitive to this mast rake angle, so change
it
> in increments of about 1/2" at a time.  Note, a slight amount of weather
> helm is desirable because it provides feedback to the helmsman, thus
> allowing
> him to steer a better course.  Excessive weather helm tends to tire the
> helmsman out.
>
> Once I'm happy, I lock the adjustment in place by taping the lock nuts on
> the turnbuckles.  I find I only need to do this adjustment once.  The
> Rhodes 22 is such a strongly built little boat that nothing ever seems to
> stretch or bend.  I do check the side-to-side upper sidestay length at the
> beginning of every season; but, it's never changed in the 13+ seasons I've
> been measuring it.  Trailering set-up only involves adjusting the lower
> sidestays since the rest are not disturbed.
>
> As far as rig tension settings on the trailer vs. off the trailer, I've
> found the only rig tension adjustment that significantly changes is the
> backstay
> tension.  You can set the tension on the rest of the standing rigging
> according to the
> above procedure on the trailer as long as the boat & trailer are
reasonably
> level.
> It will be very close to optimum when you
> get the boat in the water, certainly good enough to do the on-the-water
> fine tuning described above.
>
> FYI, I slack off on the backstay tension when Dynamic Equilibrium is not
> being sailed.  As I mentioned above, the backstay adjuster has sufficient
> power to affect the shape of the hull.  Greatly exaggerated, imagine the
> ends of the hull being pulled upward like a 22 foot long banana when the
> backstay
> adjuster is tight!  There is no sense leaving the hull & rig under that
kind
> of stress when the boat is not being sailed.
>
> Roger Pihlaja
> S/V Dynamic Equilibrium
>
>
>
> ----- Original Message -----
> From: "Al Miller" <al.shell@verizon.net>
> To: <rhodes22-list@rhodes22.org>
> Sent: Wednesday, October 23, 2002 10:35 PM
> Subject: [Rhodes22-list] Standing Rigging and Tension
>
>
> > Hi All,
> >
> > I read some time ago on the list about a neat method of using a
> > Loos(sp?) gauge to correctly tension the standing rigging on the Rhodes.
> > For the life of me I cannot find the article, even though I have about a
> > year's worth of saved mail for technical info.
> >
> > Will someone please point me in the right direction so that I can locate
> > this article?  Maybe a re-post would be helpful to others, too.  I found
> > a Loos gauge for the 1/8 inch wire used for the rigging, but it was not
> > the "pro" model.  Would the standard be adequate?
> >
> > Thanks in advance,
> >
> > Al/Michelle Miller
> > S/V Mishka
> > Tampa, FL
> >
> >
> > _________________________________________________
> > Use Rhodes22-list@rhodes22.org, Help? www.rhodes22.org/list
> >
>
> _________________________________________________
> Use Rhodes22-list@rhodes22.org, Help? www.rhodes22.org/list