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by Tom Causin (from the 2000
Region 3 Regatta Report)
As far as sails was concerned this event could not be used as a measure
of what was best. There was drafting Mylar, Icarex, and Tri Spi as the
three predominant materials being used. All but two boats used the same
materiel for both sails, the two boats with differing combinations for the
Main and Jib, and the captains for these were Danny Thomas and Steve
Radloff , both of whom made there own sails, and as can be seen from the
results Danny's worked very well. Check out DT Sails, Danny will make you
a set. Four sets were from Carr one set came from an unidentified source
in Las Vegas, the remainder being a combination of home made and those
made for AMYC club member by Brian Roberts.
Sails were a different matter, only one Jib sail exceeded the maximums
and that was less than a 1/8th inch at one of the leach points. Several
mains were below the limit and in one case a sail was below minimum on all
three leach points. The race committee did not consider the amount to be
significant, and therefore did not disqualify any sails. It may be a
coincidence but the small main large jib combinations were all in the top
half of the finishers. Brian Roberts had to switch boats during lunch
(sail servo installation failure) and his backup boat had a small (under
limit) jib and maximum limit main, yet managed a fifth. Inconclusive
conclusions.
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from VRC Forum
Simon Clarke:
After studying a few pics of various Victorias in action, I noticed
that some boats have the jib head attached to the mast at the masthead,
and others at points around the jenny strut area. Which is better, a
higher or lower attachment point?
Hal Slentz-Whalen:
Quick answer may not be quite accurate but believe there are two
reason to attach near baby stays = rules and it's faster.
1) believe the rules require a forestay attachment near the baby stays
in kit instruction terms...probably a certain point above the bottom of
the mast in inches....and
2)would emphasize that the Power of the Jib is coming upwind by Jamming
Air (Venturi) thru the jib and main. The leach (back edge) of the jib
should come as close to the main's luff (running close hauled the leach
looks parallel to the luff of the main) and would overlap to increase
pressure over the camber of the main if the sail plan (jib club) would
permit....like you see in the America's Cup 2000 boats (Jibs overlapping
the mains).
A.J. Moritz:
Simon, you have raised a good question. In theory, the head stay
attached/placement should be in compliance with what the originally kit
rigging instructions show. As I understand it, if the Vic Class Rules do
not otherwise state, the masthead arrangement for jib stay and/or jib
head is not permitted.
The jib head stay's attachment point is at approximately 6.0" when
measured from the top of the mast. From what I understand, the Class
Rules does provide up to 1/4" (+/-) variance on all rigging
measurements excluding sails.
I have not seen a masthead arrangement on a Victoria until viewing the
jpg (BIG BLUE) that you have referenced. If the Class permitted this, I
do not believe it would be beneficial to the Vic's performance. In some
other open classes like the 36/600, masthead configured rigs are
permitted and as such, do benefit in up wind light air performance due
to their very high aspect ratios.
In my opinion, its very important that all Vic skippers adhere to the
one design concept. Hull, appendages, weight rig/sail plan control is
essential in keeping with the spirit and intent of a one-design class
concept and preventing the watering down effect. The CR19 and Victor
Soling 1M Classes are very strong due to their strict one-design
control. Its paramount to any one-design class to stay the course and
vote on motions for change, modification or rule revisions put forwarded
from the rank-n-file.
Brian Roberts:
There have been many changes to the Victoria above the water line,
but within the limits of the rules, even though there are loop holes. It
is this freedom that gives the owner chance to experiment. It is one of
the reasons I chose a Victoria over a CR914. So I will vote for freedom
above the water line at every opportunity, including the jib attachment
point.
The instructions measure from the join up and there is no measurement
for the join item (BJ0108), we (Victoria owners) have imposed a rule for
overall mast height.
My join is approx 6" in length, therefore I am within rules.
Now where "can" the jib be on the fore stay, if the boom has
to be 1.5cm from the deck?
Tom Causin:
Go back and read the How to section articles by John Forester and Rod
Carr, both members of the Victoria "technical Committee". It
seems to me that playing with the rig above water is --to a point-- very
legal! I've played with using a masthead rig this season. Found it to be
very fast almost to the point of argument! But I bet I return to a 7/8's
rig next season because of AJ making sense and e-mails I've had with Rod
Carr along the same subject. It is right to question these and other
rules we have. Some rules have holes big enough in them you could drive
a truck through. Others are direct and leave no room for interpretation.
There is only 1 true one-design out there!! The RCLaser! I'm not sure
the tell-tales I have on my sail are legal!
A rule I question is the the LENGTH of the masthead crane. I think the
point to begin the 3 inch measurement is the back of the mast. After all
what matters is the point to which you can attach the backstay right? I
can't think of any reason why anyone would extend the front of the mast
crane. That is for 36/600's and ODOM's (right AJ?). There is no
definitive starting point for that measurement and since the rule is
there ..it should have one!
Spreaders--- I agree with John and Rod and I bet AJ. Only one set is
needed! Placement on the mast is the fun part there! Find a picture of
Hal's Victoria from the Region 2 RCCR and you will see a 4 spreader
rig!! And boy its hard to beat him too! In any case just remember to
watch the other boats out there on the race course --because all it
takes in one bad tack or a missed wind shift to make all of the go fasts
--not work!! But I know you'll look good!! :-)
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by Alan A. Bédard
It's the airfoil (wing like) curve of a sail that develops upwind
thrust for a sailboat. Even a flat sail will shape itself from the mast to
form an airfoil, but to take better advantage of the wind when pointing,
especially in light airs, sails are often designed with extra curve
(fuller). How much shape (fullness) you add is a matter of personal
preference and there are many texts that cover it in much greater detail
then this short article will attempt. All I will cover is the basic
techniques used to add fullness to sails, (Broadseaming and Luff Curve)
and my simplified application to make a single panel (one piece) sail
without any sewing involved.
For the easiest and lightest sails, I use polycarbonate kite/sail
cloth, available at most kite stores (on-line or in a big city near you).
It's available in a variety of colors, doesn't stretch out of shape,
resists ripping, and fabricates as easy as cutting and taping (which is
all you will be doing).
[BROADSEAM - A seam in a sail, in which the edges of neighboring panels
are cut in a convex curve, so that when they are sewn together the
resulting taper in the panels forces fullness into the sail.]
Full size sails are assembled by seaming (sewing together) multiple
panels of cloth together. The most common technique of adding shape to a
sail is to increase the area of the sail in the middle by broadening the
seam when putting panels together. Hence the term broadseam. There are all
sorts of formulas and techniques for determining the amount (and where) a
seam is broadened (made wider). Usually the seam is normal (no extra
width) at the luff, then widens to it's maximum amount about 1/3 of the
way across the sail, and then tapers back at the leach. What makes this
technique difficult is that only a little extra width will add a lot of
shape to the sail, and if the broadening isn't done smoothly, then the
sail will be lumpy. At the scale of a Victoria sail, the broadening is
usually only a few millimeters.
Another way to add shape to a sail is to cut a curve (a positive or
convex curve) into the edge of the sail at the Luff . If the mast is
strait, then the extra material at the middle of the sail will be displace
outward to produce a more curved (fuller) sail. This is the easiest way to
add curve because it doesn't involve any precision cutting and seaming of
the sail. It's also a necessary part of a sail if you are using a flexible
mast. The flexible mast has the advantage of letting you fill or flatten
your sail by decrease or increase the bend in your mast, which will use up
less or more (respectively) of the luff curve material.
Making a Sail, Step by Step:
- Cut your sail as a single piece, using the class rules as your
guide. Make sure to leave an extra 3/4 inch all around.
- Measure a strait luff line from the Head to the Tack (leaving 3/4
inch extra fabric for the luff curve).
- Make your 3/4, 1/2, and 1/4 marks on the Main. The broadseam dart on
the Jib is marked 91/2 inches up from the Tack (forward lower corner
of sail).
Note: The Jib dart is cut parallel to the foot of the Jib,
perpendicular to the Leach. . The class specifications measures the
jib perpendicular to the Luff.
- Cut and patch your darts. (See Below for details.)
- Once the darts are cut, joined, and patched, re-measure the luff,
and add a 1/4 to 1/2 inch luff curve. (Mark 1/4" from strait luff
line at 1/2 mark, measure and draw curve as you would with leach
curve.)
- At 3/4, 1/2, and 1/4 marks, measure sail to Leach from Luff Curve
line.
- Mark and cut the Luff Curve.
-
- Reinforce the corners (Head, Tack, and Clue).
- Add batten pockets (up to but not beyond the dart patch) as desired.
- That's it. you're done. Ten easy steps to making your own sail.
Broadseaming with Dart:
Since the sails for the Victoria can be made from a single piece of
material, it occurred to me that it doesn't make sense to cut the material
into panels just so I can use broadseaming to add shape. Taking a hint
from cloths designs/patterns, I use a dart, cut from the luff towards the
leach. I cut a dart at the 3/4, 1/2, and 1/4 points in the sail (see class
restrictions/specifications). How deep you cut and how wide you make the
dart will determine the fullness of the sail. For the Victoria, I use the
following measurements:
Main Sail
|
| Measure |
Cut Length |
Cut Width |
| 3/4 |
1 1/2" |
1/8" |
| 1/2 |
2 1/2" |
*3/32" |
| 1/4 |
4 1/2" |
*3/32" |
Jib
|
| Measure |
Cut Length |
Cut Width |
| 9 1/2" (from tack) |
3 1/2" (parallel to foot) |
1/16" |
| * = corrected measurement |
Measure the length of the dart from the Luff Line and the width of the
dart along the Luff Line. Mark the cut lines from the edge of the fabric
to the inside mark (see example below). Cut the triangle of the dart with
a scissors. Avoid using a knife as this may damage the material unless the
knife is very sharp.
Once the dart is cut, place a piece of masking tape behind the material
and then bring the edges of the dart together.
Once the sailcloth at the dart has been butted together, cut a patch of
sailcloth to fit over the seam and a little beyond it. (I use 1/4 inch
wide double sided tape to attach everything to my sails, so I cut my patch
1/2 inch wide and 1/4 inch longer then the dart.) Attach the patch over
the dart and smooth out the seam. Remove the masking tape. You will only
need to put a patch on one side.
 
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from VRC Forum
Bob Dockrell:
I spoke with some some folks who use MICA
film ( The old material used for covering RC airplane wings ) for
making sails. I purchased some and it appears strong enough but I was
wondering if anyone else has tried using this material on their Vic and
what their experience has been.
Rod Carr
Mica film does a fine job as a sail material. It has a couple of
major shortcomings. First, the material creases easily, so handling the
sails when off the boat becomes a test of your willingness to be careful
and treat them gently. The second is the inability of the material to
hold stitches in high stress areas, an adhesive material seems best for
clew, tack and head patches. I've produced micafilm sails for even the
big EC-12's and they do the job along with being a pretty opaque white
if you choose that color. For competition, our recommendation is the
tested TriSpi 40 with its excellent shape holding capabilities.
A.J. Moritz:
I have not personally seen or heard of anyone using MICA AKA Monocoat
[Ed Note: Micafilm®
and MonoKote® are two different
(normally) model aircraft covering materials] or film other then .2 mil
drafting mylar. Your better off purchasing some 1/2 Icarex. With
lightweight films, it's very difficult to install the necessary
reinforcements needed to distribute the loads.
Alternatively, Maritime Products offers high performance sails that
include luff pockets "sewn", stainless steel micro grommets,
draft stripes, Victoria Class std "V" insignia, tack, head and
clew reinforcements. Jib includes 50lb Spectra forestay inserted in the
luff. The material used for these sails is bullet proof, 50% greater
bursting strength than many standard sail materials used by others. This
material also has 50% less wrap stretch which promotes better sail shape
with less high wind distortion, excellent strength to weight ratios,
less moisture absorption and low air permeability. Each set comes with a
complete and detailed set up procedures including detailed drawings
showing measurements, attachments etc. Also, tuning procedures for wood,
carbon spars and adjustments for different wind conditions.
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