Boom Furling?

[chris20636]

While playing around with the rigging on my first sail outing, I
figured out that the big crank on the front of the mast turns the
entire boom. I get the general idea of using this to shorten the
main sail. However, can anyone point me to information (or has a
good write up) on the nuts and bolts of how to use this?

Thanks,
Chris
V2933 Renee
Chesapeake Bay, USA

 

[stevebirch2002]

Hi Chris

Yes this is called roller boom furling for the mainsail. It is quick and
easy to do but has two major drawbacks.

1. Once furled the shape of the mainsail is lost and the efficiency
suffers considerably.
2. You cannot easily use a kicking strap so you are unable to get
the sail falt when trying to point close-hauled.

The best way to reef the main is to fit and use slab reefing (Jiffy
Reefing). Not difficult to fit and overcomes the problems of roller boom
reefing. If you need any more details on slab reefing then drop me an
email at steve@...

Kind Regards

Steve Birch Vega "Southern Comfort" V1703

 

[mocap1]

Strve,

Have I been laboring under a misapprehension all these years? I thought the kicking strap (boom vang) was used off the wind. Going to windward the sail and mainsheet traveller are centered; the sheet pulls straight down on the boom, flattening the sail. Off the wind the sheet pulls at an angle to the boom and is ineffective in flattening the sail, hence the vang.

When I was younger, on a nice day I enjoyed serving as a boom vang by sitting on the boom while going downwind. I still do it once in a while.

Although common, I don't think attaching the vang to the base of the mast is as effective as attaching it somewhere along the rail, where has a better angle, and can also act as a preventer. Of course it you do this, you have to use two vangs, maybe more lines than you really want on a boat the size of the Vega.

Mort

 

[mocap1]

Ease the halyard nd turn. turn the crank. Don't forget to take the sail stop out of the mast groove. That's all there is to it. The result is a shorter sail with a poor aerodynamic shape. Steve is right, jiffy reefing is a superior system.

Mort

 

[stevebirch2002]

Hi Mort

If you are close-hauled and reefed you will find the mainsail trying to
lift. To counter this you need the sail flat and a kicker is ideal and
should be connected at about 45 degrees to the base of the mast. This
will give a downwards pressure and with a mast/boom Cunningham
(downhaul) will keep the boom down and the sail flat.

I am no expert at sail trimming but having sailed our chairman's Vega in
a race as crew with a Force 6/7 on the nose our reefing was awful as he
has the boom furling only. I have tried for the last four years to get
him to change and finally this winter he will be doing it!!! Nagging
always works in the end.

Kind Regards


Steve Birch

 

[chris20636]

Thanks Mort. I plan to add jiffy reefing when I get the funds to purchase a new mainsail. In the mean time, it's nice to know how to use the original reefing gear if it's ever needed.

Chris

 

[mocap1]

Next time you are close hauled, reefed or otherwise, center the traveller and sheet in. Then tighten the vang. I'll bet you don't see any significant difference. Not so off the wind.

The Cunnigngham hooks into a hole in the sail, for some reason called the "Cunnigham Hole", and flattens the sail; it has no effect on the boom. Perhaps British and American terminology is different.

You are not using a sliding gooseneck are you?

Mort

 

[wxt8981]

Hi all:
I've been reading with interest about 'reefing'. I'm using
the original roller reefing; it's not too often- only when
the wind picks up a lot, then I reef the main, when's
blowing more, than I change the jib with the storm jib,
though that has happened only about a dozen times in my
plus
thirty years of sailing my Vega.
I do use the Cunningham a lot; to adjust the main for
proper
'fullness'- unless I just sail for fun and don't care if
I'm making 5 or 5.2 knots....
By the way- I've been away most of last Summer- I'm happy
to be back- and, since I'm in Florida, can sail my Vega
again....
Wilhelm
Vega 257

 

[stevebirch2002]

Hi Mort

On quite a few of the Vegas in the UK they use a sliding boom as the
roller boom furling is sometimes on the boom and not through the mast. I
will have a go at what you say next season, sure you are right but Mike
Freemans' mainsail sure went into the air as we were pointing and we had
the mainsheet tightened as much as possible.

Cant wait until the next IFR (July 2004) in Marstrand, Sweden. There
will be over one hundred Vegas and all the expert Vega sailors. Makes me
look like an ametuer. I managed to come 34th out of thirty two finishers
in the 2000 IFR at Hoorn in Holland????? Even the Vegas that managed to
finish just two of the four races ended up in front of me. Turned out to
be a badly stretched genoa that happened when I lost my mast the
previous season and towed the genoa behind the Vega for an hour. Didn't
think my sailing could have got that bad in two years as I won the
Criusing Class in 1998 on The Medway (IFR98).

Kind Regards



Steve Birch

 

[stevebirch2002]

Hi Wilhelm

I wondered where you had been, not heard from you for a while. Welcome
back.

Steve B

 

[florance.anderson]

I enjoy sitting on that seat on the sail serving as a vang, too. The gently
breezes of mid summer in Charleston.

Florance Anderson

 

[imbissfrank]

Welcome back Wilhelm,
I was beginning to believe you weren't going to get involved in this "boom furler". You didn't disappoint me. (personally I use jiffy reefing).
Frank Gallardo Jr, V-2184, Cin Cin

WL wxt8981@... wrote:

 

[johngillwill]

after 30 years with a vega
a) purchase what is known as a boom claw,a cast iron device with two
wheels which fit around the boom.
b) position this at the original boom vang/kicking strap (whatever
technology you are happy with).attach a strop to the end of the
boom,aft end of boat,this will give you a replacement.
the strop is sometimes colloquially known as a widowmaker, when you
sail with it you will appreciate the name.
c) it was originally very well recognised that unless there was great
cooperation between whomsoever was doing the rollong at the mast and
the helmsperson, standing on the cockpit locker lid and tensioning the
outhaul in unison then this would result in a baggy droopy sail. the
recommended way to solve this problem was to roll a sail bag into the
set up at the after end of the boom, after you have forgotten once or
twice when taking the reef out then this method has been taken out of
the equation, unless you have an unlimited supply of sailbags.so
d) either yourself or your sailmaker insert a cringle about 6/8
inches or so on the leech up from the boom and rig so that you can
take in this small amount of sail prior to rolling the reef into the
main.bingo lots less droop.
e) some older wooden boats had a triangular shaped fillet at the end
of the boom which gave the same result
f) you now should have a system which is the envy of all those whoe
think jiffy reefing is the bees knees as you have infinite choice of
the size of sail you require compared to the at most choice of three
sizes of main that jiffy reefing can give you

 

[wxt8981]

Hi Steve

nice to hear from you again- did you make it to Florida?
Sorry, I wasn't here and no way to contact me (I traveled
in South-East Asia).

I just came back from my boat- changed the oil and
filter(s) for the engine, and greased the stuffing box.
She's ready
for sailing- it's a bit blustery right now (and not as
warm), but I'm looking forward to have a good sail.....

Take care..... Wilhelm

 

[wxt8981]

Hi.)
what you're writing about raking the mast for or
aft is quite important- if you're racing! Though
under normal conditions, it's a good idea to have
some weather helm (the opposite to lee helm, where
the boat will fall off the wind.) In most common wind
conditions- I would sail closed hauled and hold the
tiller against the palm of my hand, there should be some
pressure against the palm- in other words- the boat
would like to round up- gently- and that would be just
about the correct rake- and I would adjust the stays
accordingly- and leave it there!
By the way- should you ever fall overboard (when sailing
alone), you'll appreciate to see the boat rounding up
and not sailing away- though that wouldn't help much for
me,
because I use my auto-pilot just about all the time.
Happy sailing... Wilhelm

 

[mocap1]

I would take issue with some of Alisdairs statements.

A boom vang, on a boat such as the Vega which has a real traveller located directl;y below the boom, is used only when off the wind. Consider this: The forward end of the boom is attached to the mast such that it can rotate about the aft side of the mast both horizontally and vertically. IT CANNOT MOVE UPWARD. The aft end of the boom is attached to the mainsheet which in turn is connected to the traveller. When sheeted in hard, the end of the boom assumes a position over the traveller. It can translate horizontally a very small amoun, but IT CANNOT MOVE UPWARD. We thus have both ends of the boom prevented from moving upward. Adding additional downward force, such as with a vang, will do nothing to the shape of the sail, and will not move the boom.

In Looking at Sails by Banks and Kenney , an authoritative text, they state: " If the mainsheet traveller had the the same sweeping length of arc as the boom could swing, it would be easy. We could say that all the up and down adjustment of the boom, controlling mainsail leech tension could be the role of the mainsheet........Once outside the the arc of the traveller, the vertical load on the clew must be taken by the vang, and the mainsheet must take over the role of the traveller in presenting the sail to the wind at the right angle"

In Sail Power by Wallace Ross, he states: "....As you sail even further off the wind, you want to set the carriage even further outboard but you have reached the end of the track. At this piont the vang takes over.The vang should be presecured so that when you have to ease the mainsheet to allow the sail to go further outboard, you still have a firm control over the leech."

To get the best performance going to windward, the boom should definitely not be sheeted over center. This is something that is sometimes done in light airs, probably more to give the crew something to do than for any real benefit.

Ross suggests that when going to windward in very light air, 0-2 knots, it is important t have the boom trimmed well out until the boat gains speed, such as in a puff. He says that when the wind is in the 2-5 knot range, the boom '.....should be trimmed to the FURTHEST INBOARD POINT [THE CENTERLINE] and the leech should be relatively tight. (Midship travellers will need to be pulled to windward UNTIL THE END OF THE BOOM IS CENTERLINED"

As the wind increases, the boom should be kept centered until the crew is fully hiked out and the maximum heel is reached. From that point on, the sheet should be eased to keep the boat on its feet.

I have some comments about raking the mast aft, and moving weight forward, both of which can be beneficial under certain circumstances, but I doubt that anyone has read this far, so I will save it for another time.

I have heard it said that differences of opinion make horse races; I guess the same is true of sailboat racing.

Mort

 

[mocap1]

I would take issue with some of Alisdairs statements.

A boom vang, on a boat such as the Vega which has a real traveller located
directl;y below the boom, is used only when off the wind. Consider this: The
forward end of the boom is attached to the mast such that it can rotate
about the aft side of the mast both horizontally and vertically. IT CANNOT
MOVE UPWARD. The aft end of the boom is attached to the mainsheet which in
turn is connected to the traveller. When sheeted in hard, the end of the
boom assumes a position over the traveller. It can translate horizontally a
very small amoun, but IT CANNOT MOVE UPWARD. We thus have both ends of the
boom prevented from moving upward. Adding additional downward force, such as
with a vang, will do nothing to the shape of the sail, and will not move the
boom.

In Looking at Sails by Banks and Kenney , an authoritative text, they
state: " If the mainsheet traveller had the the same sweeping length of arc
as the boom could swing, it would be easy. We could say that all the up and
down adjustment of the boom, controlling mainsail leech tension could be the
role of the mainsheet........Once outside the the arc of the traveller, the
vertical load on the clew must be taken by the vang, and the mainsheet must
take over the role of the traveller in presenting the sail to the wind at
the right angle"

In Sail Power by Wallace Ross, he states: "....As you sail even further off
the wind, you want to set the carriage even further outboard but you have
reached the end of the track. At this piont the vang takes over.The vang
should be presecured so that when you have to ease the mainsheet to allow
the sail to go further outboard, you still have a firm control over the
leech."

To get the best performance going to windward, the boom should definitely
not be sheeted over center. This is something that is sometimes done in
light airs, probably more to give the crew something to do than for any real
benefit.

Ross suggests that when going to windward in very light air, 0-2 knots, it
is important t have the boom trimmed well out until the boat gains speed,
such as in a puff. He says that when the wind is in the 2-5 knot range, the
boom '.....should be trimmed to the FURTHEST INBOARD POINT [THE CENTERLINE]
and the leech should be relatively tight. (Midship travellers will need to
be pulled to windward UNTIL THE END OF THE BOOM IS CENTERLINED"

As the wind increases, the boom should be kept centered until the crew is
fully hiked out and the maximum heel is reached. From that point on, the
sheet should be eased to keep the boat on its feet.

I have some comments about raking the mast aft, and moving weight forward,
both of which can be beneficial under certain circumstances, but I doubt
that anyone has read this far, so I will save it for another time.

I have heard it said that differences of opinion make horse races; I guess
the same is true of sailboat racing.

Mort

 

[zippydoda_captain]

Let's get this right.
There are four controls for the mainsail.
The boom outhaul and Cunningham control the fullness of the mainsail.
The Boom vang (or kicker in the UK) controls the twist of the mainsail
leach.
The mainsheet controls the angle of the mainsail to the apparent wind.

If you use your mainsheet and traveler to hold the end of the boom down
you will take all the twist out of the leach, stalling the head of the
sail.

In a racing situation (upwind) you want to be sailing as upright as
possible (most efficient and faster than on the ear) you do this by
constantly playing the mainsheet. If you don't have a Vang (kicker)
controlling the leach of the main when you sheet out in the gusts the
boom goes 'up' instead of 'out' making matters worse by putting fullness
back into the sail.
Centre lining the boom usually means you're pinching to windward, again
not very fast. I rarely sheet in past the aft quarters. If you find the
main back winding behind the mast then your sheeting angles on the genoa
are probably wrong closing the slot to far.

Ray Wilton
University of Wales (Bangor)
School of Ocean Science
Menai Bridge
Gwynedd LL59 5AB
Tel: +44 (0)1248 382614
Fax +44 (0)1248 382584

 

[florance.anderson]

Thanks for the cyber space sailing lesson!

Florance Anderson
Salt
3227
1977 AlbinVega

 

[wxt8981]

Hi Ray;

you got it pretty right! Though there is a fifth control:
The rake of the mast. If you have to much weather helm
(mast farther back), then your rudder will work like
a brake- and slow you down.
Since the rake depends on the cut of the sail, I adjust
that only after I bent on new sails.. and then leave it
alone.
Wilhelm, Vega257