SAN JUAN 23
ORIGINAL SPECIFICATIONS FOR RACING
...As printed in Clark Boat Company SJ 23 Owners Manual - 1979 Edition
Measurement Rules
It is the intent of the Measurement Rules of the class to insure that boats
race and remain as nearly identical as possible within normal building
tolerances and to insure and enforce the One Design nature of the Class.
Accordingly, any equipment or modifications to equipment deemed by the class to
contravene either the spirit or the letter of these rules shall be outlawed.
Article I - General
The selection of original fittings, spars, sails and any other equipment
furnished with a San Juan 23 sloop at the time of its sale by the manufacturer
shall be within the discretion of the Clark Boat Company.
Article II - Hull Construction
1. All hulls shall be constructed of fiberglass from molds made from plugs
or forms furnished by the Clark Boat Co. and in accordance with procedures
established by the Clark Boat Co., shall be made by builders licensed by the
Clark Boat Co., and approved by the executive committee of the San Juan 23 Class
Association, and shall conform to the official specifications.
2. The mast step position may not be altered from its original manufacture,
and adjustable steps are not permitted. If the step is damaged, or if any change
is required to accommodate a new mast, the aft edge of the boltrope groove of
the mast must be in the same position when stepped as it was prior to the repair
or damage. No rotation of the mast which exceeds the usual mast step slope is
allowed.
Article III - Mast and Boom
1. The mast shall be made of aluminum.
2. Halyards must run outside of the mast.
3. Tapered masts are not permitted.
4. A masthead latch is permitted.
5. Wire halyards are permitted.
6. No stays on the mast are permitted, other than four shrouds, forestay, and
backstay.
7. Other than the standard turnbuckle arrangement, devices for adjusting the
forestay, changing the tension of the shrouds, or otherwise adjusting position
of the mast while underway are not permitted. A backstay choker is permitted.
8. Length of the mast is not limited. However, a one-half inch black band is
to be maintained on the mast, so that the lower edge of the band is to be no
higher than 26 -0 above the mast step. The sail, when hoisted, shall not
extend its topmost portion above the lower edge of the band. Another black band
must be maintained on the mast 24 -0 from the lower edge of the band to the
upper edge of the lower band. The sail shall not be downhauled past the upper
edge of the lower band.
9. If a mast is replaced, the replacement mast must be identical in all
essential respects to the mast then being supplied as original equipment on new
San Juan 23 sloops.
10. Spreaders shall hold shrouds 26 Ύ from mast (minimum).
11. The boom shall be made of aluminum.
12. Length of the boom is not limited. However, a black band one-half inch
wide shall be maintained on the boom, the inner edge of which band is a distance
not greater than 8 9 from the aft edge of the mast. The sail must not be
outhauled past the inner edge of the band.
Article IV - Rigging and Equipment
1. Rudder: The rudder shall be made of wood (which may be fiberglass covered)
or fiberglass, shall not be less than 1 and not more than 1 ½ thick, and shall
have a 2 length of any shape tolerance. Kick-up rudders are permitted, but must
be locked or pinned in the down position while racing.
2. Tiller: The tiller shall be of the general shape as provided by Clark Boat
Company and may be made of any type of wood.
3. Hiking Aids: A hiking stick or tiller extension of any design is
permitted, but no other hiking aid above deck level is permitted. Hiking straps
of any design are not permitted.
4. Keel and Ballast: Internal lead of 900 pounds from the existing or
identical mold shall not be altered in either section, profile, weight or
placement. Other interior lead ballast or any unusual placement or gear that
would provide the effect of inside ballast is not allowed. The centerboard
stirrup may be adjusted as desired, however, the centerboard slot may not be
gasketed and the centerboard shall remain free to travel up and down while
racing.
5. Jib Sheet: Other than by holding the jib sheet by hand, no reaching
devices are permitted. The blocks may be attached to a sliding track which
provides adjustable positions fore and aft. The blocks may be attached by means
of metal fittings or wire to extend the blocks but such extenders shall be so
designed and rigged as not to be adjustable during a race.
6. Jib Halyard Latch: A winch or other similar device for tensioning the jib
halyard is permitted. Jib cloth tensioning devices other than rope or wire luffs
are not permitted.
7. Spinnaker Pole: The spinnaker pole may be made of any material. Its length
shall not exceed 9 6, measured from end to end. A lanyard is permitted. The
spinnaker pole must be used and connected to the mast when the spinnaker is set,
and must be used on the side opposite to that on which the boom is carried.
8. Whisker Pole: The whisker pole may be made of any material, length and
type. It is to be used only with the jibs, and must be attached to the mast
while in use. It must be used only on the side opposite to that on which the
boom is carried.
9. Anchor: A suitable anchor, chain, paddle, and boarding ladder shall be
required. Bunk cushions supplied by the manufacturer or cushions equivalent to
them should be on board.
Article V - Sails
1. General
a. San Juan 23s may carry mainsail, working jib, 115% genoa, and 150% genoa and
spinnaker, as shown in the sail plan and as herein specified.
b. Use of sails other than main, working jib, 115% genoa, 150% genoa and 153%
spinnaker shall not be allowed.
2. Mainsail
a. The mainsail shall attach to the mast and boom by boltrope groove.
b. Luff and foot measurements shall be controlled by the black band system.
c. The leech shall not exceed 245. Batten length maximum: upper, 21, two
middle 23, and lower 21.
d. Battens shall divide the leech diagonally into equal section with 2
tolerances to allow sailmakers to avoid seams with batten pockets.
e. Hollows between battens in leech not to exceed Ύ in roach.
f. Headboards shall be triangular, with the upper side of the triangle not
exceeding 5 in length.
g. The mainsail shall be made of 5.0 oz. Or heavier Dacron or other synthetic
materials.
h. A cunningham or sail control grommet is permitted to be used while racing.
i. A reefing zipper on the mainsail is not permitted to be used while racing.
Roller reefing or jiffy reefing is permitted.
3. Jibsail (working)
a. The dimensions of the working jib shall not exceed 85 square feet.
b. The working jib shall be made of 5.0 oz. Or heavier dacron or other synthetic
materials.
c. Jib foot roach must be a fair, continuous curve.
d. One small window of clear plastic, 2 sq. ft. maximum area, is permitted.
e. Jib roller devices are permitted.
f. No battens in the jib are permitted.
4. 115% Genoa
a. The 115% genoa shall be made of 5.0 oz. Or heavier dacron or other synthetic
materials.
b. The dimensions of the genoa measured with 5 lb. Tension edge of sail to edge
of sail shall not exceed the following: Luff 226, LP 114.
5. 150% Genoa
a. The 150% genoa shall be made of 3.5 oz. Or heavier dacron or other synthetic
materials.
b. The dimensions of the 150% genoa measured with 5 lb. Tension edge of sail to
edge of sail shall not exceed the following: Luff 286, leech 26), LP 143.
6. Spinnaker
a. The spinnaker shall be made of a .75 oz. Or heavier woven nylon material.
b. The spinnaker halyard sheave shall be attached to the masthead.
c. Spinnaker sheet fittings may be placed at any position on the deck, but not
so as to extend outboard of the deck.
d. Maximum dimensions of the spinnaker, measured with sufficient tension to just
pull wrinkles out, shall not exceed the following: Luff 277, maximum girth
146.
It is my intent to suggest to the association just forming that we set up a
Rules Committee or act as a committee of the whole to review the above
Measurement Rules of the class as originally promulgated with the purpose of
approving reasonable deviations in equipment or modifications to equipment for
the purpose of maintaining racing competition in the class while at the same
time being reasonable in light of the fact the San Juan 23 is no longer in mass
production. It would seem some handicap could be assessed for modified equipment
which provides a clear advantage in racing without outlawing that equipment
just because it contravenes either the spirit or the letter of these original
rules.
-Chuck Van de Wetering
