[bolger] Re: Boomed Headsails
> Elsewhere on this thread, someone (Peter?) suggested (inconnection with
> my posting regarding Bolger's description of a "20's" racing slooprig, I
> believe) that leading the sheet forward from the traveler (or"horse") to
> near the tack of the sail provided some "vang" effect. I'm notcertain that
> it does so, and would be interested in hearing other opinions on thesubject.
I probably shouldn't have made this remark. Clearly, if the sheet is
led from the end of the jib boom to the deck aft of the jib boom
gooseneck, the sheet applies some downward pull, but the mechanical
advantage is so small that the effect is probably negligable. I plead
the Bolger did make a similar comment with respect to a mainsheet
somewhere.
My understanding is that the reason to lead the jibsheet forward is to
avoid any left/right forces in the sheet system. Other simple systems
tend to center the jib boom. When the sheet is eased enough to get the
jib out for a reach, it is so loose that the boom also rises, and the
sail shape is terrible.
For completeness, we should mention that there are high class racing
boats with self-tending jibs. They use a long traveler bent in a
circular arc and mounted in the plane perpendicular to the jib stay.
The set of the jib can be perfect for beating and pretty good for
reaching. These boats all use spinnakers downwind. The important point
illustrated is that being imaginative about your traveler could result
in a system that works as well and is simpler than a jib boom.
Peter
I share your interest in the balanced club jib idea. Bolger has fairly
complimentary things to say about this rig, as I recall. I'm too lazy tonight
to try to locate the scattered references in "100 Small Boat Rigs", but I
believe at one point he states that it produces the best headsail set for the
least load on the mast, but on another states that it is not very good
(compared to a conventional jib on a headstay, I suppose) for sailing to
windward. However, I may be completely mistaken. Rig #91 in 100 SBR is that
of "Vendredi Treize" and he notes in that discussion that he suggested to the
designer (Carter Offshore) that balanced clubs would have advantages over the
staysails it was eventually equipped with. This is curious, as my (admittedly
falible) recollection is that "Vendredei Treize" was intended to sail to
windward against the westerly to take advantage of the shorter great-circle
route, while its principal and ultimately victorious, competitor took the
longer trades winds route. The stategy of "Vendredi Treize" was based on
getting superior windward performance - which would be inconsistent with my
recollection that Bolger elsewhere states that the up-wind performance is not
optimal. In his discussion of this alternative to the design as executed he
does say "...it would have been hard to get enough halyard tension to make
the sail stand in heavy weather", which would may be inconsistent with the
(possible) observation about low loads on the mast(s). I certainly don't know
and have never actually seen, much less sailed with such a rig.
Peter V.'s cautionary comment (as I take it) on reducing (dropping?) sail
finds some support in the commentary on Rig #91. Since the jib is necessarily
set flying, it is not restrained by being hanked to a stay when being
lowered. Bolger says that such a rig would require slack jackstays aligned
with the pivot axis of the sail to restrain it while being lowered. Still,
the notion of having the leech tension the luff is one of those elegant ideas
that make reading Bolger such a gratifying experience.
Elsewhere on this thread, someone (Peter?) suggested (in connection with
my posting regarding Bolger's description of a "20's" racing sloop rig, I
believe) that leading the sheet forward from the traveler (or "horse") to
near the tack of the sail provided some "vang" effect. I'm not certain that
it does so, and would be interested in hearing other opinions on the subject.
(actually I'm pretty convinced that it doesn't, but at the moment I'm at a
loss as to why it is necessary or desirable to run the sheet forward for any
reason). I'd be really interested in hearing more opinions on this subject.
I see from other comments that "103 Small Boat Rigs" is an actual
publication, not just a typo. Would anyone care to fill me in on what has
been added and/or deleted from "100 SBR"? I hope Rig # 70 "Jibheaded with
staysail and very small foresail" has not been deleted. It would be nice if
the radically assymetrical sailplan of the "Scooner Wyoming" shown on the
PB&F advertisement in MAIB was elucidated.:)
Bill in MN
complimentary things to say about this rig, as I recall. I'm too lazy tonight
to try to locate the scattered references in "100 Small Boat Rigs", but I
believe at one point he states that it produces the best headsail set for the
least load on the mast, but on another states that it is not very good
(compared to a conventional jib on a headstay, I suppose) for sailing to
windward. However, I may be completely mistaken. Rig #91 in 100 SBR is that
of "Vendredi Treize" and he notes in that discussion that he suggested to the
designer (Carter Offshore) that balanced clubs would have advantages over the
staysails it was eventually equipped with. This is curious, as my (admittedly
falible) recollection is that "Vendredei Treize" was intended to sail to
windward against the westerly to take advantage of the shorter great-circle
route, while its principal and ultimately victorious, competitor took the
longer trades winds route. The stategy of "Vendredi Treize" was based on
getting superior windward performance - which would be inconsistent with my
recollection that Bolger elsewhere states that the up-wind performance is not
optimal. In his discussion of this alternative to the design as executed he
does say "...it would have been hard to get enough halyard tension to make
the sail stand in heavy weather", which would may be inconsistent with the
(possible) observation about low loads on the mast(s). I certainly don't know
and have never actually seen, much less sailed with such a rig.
Peter V.'s cautionary comment (as I take it) on reducing (dropping?) sail
finds some support in the commentary on Rig #91. Since the jib is necessarily
set flying, it is not restrained by being hanked to a stay when being
lowered. Bolger says that such a rig would require slack jackstays aligned
with the pivot axis of the sail to restrain it while being lowered. Still,
the notion of having the leech tension the luff is one of those elegant ideas
that make reading Bolger such a gratifying experience.
Elsewhere on this thread, someone (Peter?) suggested (in connection with
my posting regarding Bolger's description of a "20's" racing sloop rig, I
believe) that leading the sheet forward from the traveler (or "horse") to
near the tack of the sail provided some "vang" effect. I'm not certain that
it does so, and would be interested in hearing other opinions on the subject.
(actually I'm pretty convinced that it doesn't, but at the moment I'm at a
loss as to why it is necessary or desirable to run the sheet forward for any
reason). I'd be really interested in hearing more opinions on this subject.
I see from other comments that "103 Small Boat Rigs" is an actual
publication, not just a typo. Would anyone care to fill me in on what has
been added and/or deleted from "100 SBR"? I hope Rig # 70 "Jibheaded with
staysail and very small foresail" has not been deleted. It would be nice if
the radically assymetrical sailplan of the "Scooner Wyoming" shown on the
PB&F advertisement in MAIB was elucidated.:)
Bill in MN
Remember also that this is rigged only on the staysail on a cutter rigged
boat-the idea is to only have to handle one set of sheets-and on Island
Packets, you need all the sail, all the time.
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
boat-the idea is to only have to handle one set of sheets-and on Island
Packets, you need all the sail, all the time.
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
> -----Original Message-----
> From: Peter Vanderwaart [mailto:pvanderw@...]
> Sent: February 23, 2000 9:25 AM
> To:bolger@...
> Subject: [bolger] Re: Boomed Headsails
>
>
>
> > Would it be an advantage to be able to vary the length of the boom as
> well as control the height of the clew end?
>
> This is a tricky question. The absolutely optimum sheeting point for a
> jib changes with each change in point of sail and wind strength. That
> is why the decks of racing boats are covered with tracks. And for any
> point of sail other than close-hauled, the ideal point is to lee of the
> boat, out over the water. Now that the racing rules allow us to use the
> whisker pole on the same side of the mast as the boom, we find it very
> useful to pole out the jib to leeward while on a close or square reach.
> This requres a shorter pole than the downwind whisker pole. My pole is
> adjustable length.
>
> In general, I think that a the best shape for reaching is fuller (more
> curved) than for beating, i.e. the clew is closer to the tack. This
> works out OK with a jib boom that is goosenecked somewhat behind the
> tack. For general cruising purposes, I think that variable length is
> not required.
>
> I should say that when I used the word 'vang' for the jib boom I had in
> mind a short length of rod or wire that would be 'adjust once and leave
> be'. For a small homebuilt boat, maybe a hardware store stainless steel
> turnbuckle could be a major part. I don't think that vertical
> adjustment is particularly crucial, especially in a cruising boat, and
> certainly did not have a block & tackle arrangement in mind.
>
> I think I finally realized why the Island Packet arrangement did not
> have the clew attached to the boom: as the sail swings out, the clew
> lifts due to the rake of the forestay.
>
> Of course, nothing works really well on a very broad reach or dead
> downwind. On the lee side, the jib is blanketed and shape does not
> matter much. Going wing and wing, you may have trouble getting the jib
> out to windward and keeping it there, especially if the helmsman is not
> attentive.
>
> The point of a jib boom, as I see it, is to reduce the effort required
> to handle the jib. Multiplying the controls defeats the purpose.
>
> Peter
>
>
>
> ------------------------------------------------------------------------
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> This may be a simplistic question, but I've been playing with aYes, of course. I don't have first hand experience with any of these
> boomed jib on a low tech swing rig I've been designing, and what about
> the old approach of the balanced club jib? Doesn't that self vang? As
> the jib boom tries to rise it increases the tension on the luff of the
> jib?
things, and especially not with the balanced club. Mr. Bolger reviews
the tradeoffs in Small Boat Rigs, and I believe that the weak point of
the balanced club is heavy weather. It would seem to me that since it
is an unusual rig (at least here and now) that you want to be careful
about the design and construction of the gear and especially the sail.
You don't want to spend the money and not have it work properly, and
there are probably some subtle points that are easy to overlook. You
need to balance both luff and leech tension (in order to keep the boom
level) and the rotational force in front of and behind the stay (in
order to make the jib swing with the wind properly). Both
considerations affect sail shape.
And then, there is the question of what is required to furl the sail,
or unbend it and take it home.
Peter.
Peter,
This may be a simplistic question, but I've been playing with a
boomed jib on a low tech swing rig I've been designing, and what about
the old approach of the balanced club jib? Doesn't that self vang? As
the jib boom tries to rise it increases the tension on the luff of the
jib?
david beede
Peter Vanderwaart wrote:
This is a tricky question. The absolutely optimum sheeting point for a
jib changes with each change in point of sail and wind strength. That
is why the decks of racing boats are covered with tracks. And for any
point of sail other than close-hauled, the ideal point is to lee of the
boat, out over the water. Now that the racing rules allow us to use the
whisker pole on the same side of the mast as the boom, we find it very
useful to pole out the jib to leeward while on a close or square reach.
This requres a shorter pole than the downwind whisker pole. My pole is
adjustable length.
In general, I think that a the best shape for reaching is fuller (more
curved) than for beating, i.e. the clew is closer to the tack. This
works out OK with a jib boom that is goosenecked somewhat behind the
tack. For general cruising purposes, I think that variable length is
not required.
I should say that when I used the word 'vang' for the jib boom I had in
mind a short length of rod or wire that would be 'adjust once and leave
be'. For a small homebuilt boat, maybe a hardware store stainless steel
turnbuckle could be a major part. I don't think that vertical
adjustment is particularly crucial, especially in a cruising boat, and
certainly did not have a block & tackle arrangement in mind.
I think I finally realized why the Island Packet arrangement did not
have the clew attached to the boom: as the sail swings out, the clew
lifts due to the rake of the forestay.
Of course, nothing works really well on a very broad reach or dead
downwind. On the lee side, the jib is blanketed and shape does not
matter much. Going wing and wing, you may have trouble getting the jib
out to windward and keeping it there, especially if the helmsman is not
attentive.
The point of a jib boom, as I see it, is to reduce the effort required
to handle the jib. Multiplying the controls defeats the purpose.
Peter
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This may be a simplistic question, but I've been playing with a
boomed jib on a low tech swing rig I've been designing, and what about
the old approach of the balanced club jib? Doesn't that self vang? As
the jib boom tries to rise it increases the tension on the luff of the
jib?
david beede
Peter Vanderwaart wrote:
>well as control the height of the clew end?
>
> Would it be an advantage to be able to vary the length of the boom as
This is a tricky question. The absolutely optimum sheeting point for a
jib changes with each change in point of sail and wind strength. That
is why the decks of racing boats are covered with tracks. And for any
point of sail other than close-hauled, the ideal point is to lee of the
boat, out over the water. Now that the racing rules allow us to use the
whisker pole on the same side of the mast as the boom, we find it very
useful to pole out the jib to leeward while on a close or square reach.
This requres a shorter pole than the downwind whisker pole. My pole is
adjustable length.
In general, I think that a the best shape for reaching is fuller (more
curved) than for beating, i.e. the clew is closer to the tack. This
works out OK with a jib boom that is goosenecked somewhat behind the
tack. For general cruising purposes, I think that variable length is
not required.
I should say that when I used the word 'vang' for the jib boom I had in
mind a short length of rod or wire that would be 'adjust once and leave
be'. For a small homebuilt boat, maybe a hardware store stainless steel
turnbuckle could be a major part. I don't think that vertical
adjustment is particularly crucial, especially in a cruising boat, and
certainly did not have a block & tackle arrangement in mind.
I think I finally realized why the Island Packet arrangement did not
have the clew attached to the boom: as the sail swings out, the clew
lifts due to the rake of the forestay.
Of course, nothing works really well on a very broad reach or dead
downwind. On the lee side, the jib is blanketed and shape does not
matter much. Going wing and wing, you may have trouble getting the jib
out to windward and keeping it there, especially if the helmsman is not
attentive.
The point of a jib boom, as I see it, is to reduce the effort required
to handle the jib. Multiplying the controls defeats the purpose.
Peter
> -------------------------------------------------------------------------
>
>
> eGroups.com Home:http://www.egroups.com/group/bolger
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SOME CLICKS THAT COUNT!!
Feed someone.
http://www.thehungersite.com/
Save a little rain forest.
http://rainforest.care2.com/front.html/player12296
Simplicity Boats (& mirror sites)
http://members.tripod.com/simplicityboats/index.html
http://members.xoom.com/simpleboats/index.html
Here's my latest boat:
http://members.tripod.com/simplicityboats/featherwind.html
http://members.xoom.com/simpleboats/featherwind.html
Quasi esoteric musical instruments
http://unicornstrings.com
> Would it be an advantage to be able to vary the length of the boom aswell as control the height of the clew end?
This is a tricky question. The absolutely optimum sheeting point for a
jib changes with each change in point of sail and wind strength. That
is why the decks of racing boats are covered with tracks. And for any
point of sail other than close-hauled, the ideal point is to lee of the
boat, out over the water. Now that the racing rules allow us to use the
whisker pole on the same side of the mast as the boom, we find it very
useful to pole out the jib to leeward while on a close or square reach.
This requres a shorter pole than the downwind whisker pole. My pole is
adjustable length.
In general, I think that a the best shape for reaching is fuller (more
curved) than for beating, i.e. the clew is closer to the tack. This
works out OK with a jib boom that is goosenecked somewhat behind the
tack. For general cruising purposes, I think that variable length is
not required.
I should say that when I used the word 'vang' for the jib boom I had in
mind a short length of rod or wire that would be 'adjust once and leave
be'. For a small homebuilt boat, maybe a hardware store stainless steel
turnbuckle could be a major part. I don't think that vertical
adjustment is particularly crucial, especially in a cruising boat, and
certainly did not have a block & tackle arrangement in mind.
I think I finally realized why the Island Packet arrangement did not
have the clew attached to the boom: as the sail swings out, the clew
lifts due to the rake of the forestay.
Of course, nothing works really well on a very broad reach or dead
downwind. On the lee side, the jib is blanketed and shape does not
matter much. Going wing and wing, you may have trouble getting the jib
out to windward and keeping it there, especially if the helmsman is not
attentive.
The point of a jib boom, as I see it, is to reduce the effort required
to handle the jib. Multiplying the controls defeats the purpose.
Peter
> Although this means three lines to control the headsail it wouldallow for it to be self tacking, and could double to hold out the clew
when going downwind. The potential for wrecking gear poled out in this
way is worthy of not a little consideration.
>I can't help much with this but I can email you a sketch by Audemard
> I really would appreciate some futher comment
>
> Regards - Foster
(ca 1910) showing a Chinese battened jib... <grin>
> The best system would seem to be to buy, off the shelf, the bearingsystem
> used by Island Packet and fabricate a boom to fit your headsail(assuming
> the loads aren't tremendously larger.Peter Wrote
I think that the same effective geometry can be homebuilt in a lower
tech way with a simple vang on the jib boom. Since a vang requires some
more or less vertical separation between the jib attachment and the
vang attachment, it would be necessary to build a vertcal butt (sort of
a mini-mast) just behind the stem. The jib boom would be goosenecked at
the top, say 8-10" off the deck. The jib boom vang would attach to the
butt at its base, and to the jib boom a couple of feet back
I now understand the basic geometry of the IslandPacket and system proposed above but I don't have enough sailing experience to exactly visulise all the necessary parameters to getting "ideal" headsail shape. So if you will bear with me, some more questions:
Would it be an advantage to be able to vary the length of the boom as well as control the height of the clew end?
What I an thinking of here (and this may be getting to complicated to be worthwhile) is to have the boom telescope through a simple universal that will permit radial movement in a horizontal plane controlled by the sheet (the boom can swing across the deck) radial movement in a vertical plane controlled by a vang (the outer end of the boom can be held up or down).
The telescoping boom would be held out by a outhaul
Although this means three lines to control the headsail it would allow for it to be self tacking, and could double to hold out the clew when going downwind. The potential for wrecking gear poled out in this way is worthy of not a little consideration.
I really would appreciate some futher comment
Regards - Foster
> The best system would seem to be to buy, off the shelf, the bearingsystem
> used by Island Packet and fabricate a boom to fit your headsail(assuming
> the loads aren't tremendously larger.I think that the same effective geometry can be homebuilt in a lower
tech way with a simple vang on the jib boom. Since a vang requires some
more or less vertical separation between the jib attachment and the
vang attachment, it would be necessary to build a vertcal butt (sort of
a mini-mast) just behind the stem. The jib boom would be goosenecked at
the top, say 8-10" off the deck. The jib boom vang would attach to the
butt at its base, and to the jib boom a couple of feet back.
The Hoyt arrangement holds the jibboom 'up' at all times, but that is
not a functional requirement.
In the picture I saw of an Island Packet, the jib clew was not attached
to the boom. Instead, the sheet ran from the boom to the clew and back
to the boom. I don't remember the complete arrangement of the sheet.
The advice from Bolger to run the sheet forward does provide some small
vanging force, as well as a better control of the clew.
I'm not sure that in the catalog of possibilities we included the
counterbalanced jib boom - discussed in 100 SMR.
Peter
One post back in this thread someone mentioned the recent introduction by
Island Packet of a "Gary Hoyt" style boom for the staysail on the cutter
version of the boats. After re-reading Bolger's comments, I have to say the
curved boom of the Island Packets and, on a smaller scale, the Escape sail
trainer, seems to obliviate the main drawback, ie, a foot that rises off the
wind and causes sail twist. The curved boom swings in a flat arc, thus
keeping the foot of the sail down. A cursory review of this set up at the
Miami boatshow DID show a drawback of the curved boom, that is the bearing
arrangment of the foot of the boom where it attaches to the deck-any jams
here, such as those seen in various rooler furlers over the years would
cause much cursing....
The best system would seem to be to buy, off the shelf, the bearing system
used by Island Packet and fabricate a boom to fit your headsail (assuming
the loads aren't tremendously larger.
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
Island Packet of a "Gary Hoyt" style boom for the staysail on the cutter
version of the boats. After re-reading Bolger's comments, I have to say the
curved boom of the Island Packets and, on a smaller scale, the Escape sail
trainer, seems to obliviate the main drawback, ie, a foot that rises off the
wind and causes sail twist. The curved boom swings in a flat arc, thus
keeping the foot of the sail down. A cursory review of this set up at the
Miami boatshow DID show a drawback of the curved boom, that is the bearing
arrangment of the foot of the boom where it attaches to the deck-any jams
here, such as those seen in various rooler furlers over the years would
cause much cursing....
The best system would seem to be to buy, off the shelf, the bearing system
used by Island Packet and fabricate a boom to fit your headsail (assuming
the loads aren't tremendously larger.
Robert & Amy Lundy
St. Petersburg, fla.
robert@...
amy@...
> -----Original Message-----
> From:Wmrpage@...[mailto:Wmrpage@...]
> Sent: February 21, 2000 8:11 PM
> To:bolger@egroups.com
> Subject: [bolger] Re: Boomed Headsails
>
>
> Bolger's observations on headsails are rather scattered about
> "100 Small Boat
> <snip>
Bolger's observations on headsails are rather scattered about "100 Small Boat
Rigs", but I've found two discussions that may be of interest to you:
1) Rig #28 "Jibheader with low foretriangle", described as "characteristic
rig of the 1920's". The function of the jib on this rig is discussed as
principally to correct a deficiency in the main rig. Boler says, in part:
"A boomed jib like this has to have a traveler and a horse and the fall of
the sheet has to lead forward to a turning block close to the tack. It's
tempting to sheet it with the standing end of the sheet on a deck padeye to
oneside, up through a block on the boom, down to a turning block across the
deck from the standing end and so aft.... (this has certain conveniences,
which he here discusses) ...A good many cruising boats were, and some still
are, rigged this way. No racer ever was because the arrangement doesn't hold
the boom down.The sail twists, falls off at the top, draws badly and doesn't
help the mainsail. Its a bad trad off and not worth it even on a cruiser.
... "(and has certain inconveniences, which he then discusses)
As shown on his cartoon, the it is not clear that the jib is attached to the
boom only at the clew, but all the (few) examples I've ever seen were so
rigged, and I'm not sure it is physically (geometrically) possible to do it
otherwise. The gooseneck or whatever of the boom is fixed a bit abaft of the
tack. The sheet runs down to the end of the boom to a block on the horse,
then up to a block on the boom (in an effort from keeping the sheet from
snagging on the mooring bits, etc.) and forward to a point that can't be
discerned, but is presumably just aft of the "gooseneck", to pass around a
block and aft. He says the principal reason for rigging these boats so was
that the crews found having to tend both the running backstays and the jib
sheets as being more work than most crews wanted.
Incidently, the boomed jibs shown in Bolger's cartoons in 100 SBR all
have their forward ends fixed quite close behind the tack of the jib. I have
seen a boat or two with the goosenecks set quite a bit farther aft and on one
occassion received a learned lecture on the virtues of such an arrangement -
something to do with the jib setting "fuller" when the sheet is eased. I
suspect that the rig might be made to work well if carefully enough thought
out - but would require rather sophisticated dealing with sail-cut, horse
width, sheeting angles, etc. I does seem to me that the problem with the
sheet catching on excresences on the fore deck when rigged as Bolger suggests
is the better practice could be avoided by making the boom hollow and running
the running part of the sheet down the hollow interior.
2) Rig #27 "Cat with jib (cat-sloop) shows a jib secured by a pair of battens
bolted through the sail approximately perpendicular to the headstay running
to the clew. Bolger does not think it an appropriate rig for any seagoing
boat because of the danger (inevitability?) of kinking and fatigue fracture
of the head stay.
Rigs", but I've found two discussions that may be of interest to you:
1) Rig #28 "Jibheader with low foretriangle", described as "characteristic
rig of the 1920's". The function of the jib on this rig is discussed as
principally to correct a deficiency in the main rig. Boler says, in part:
"A boomed jib like this has to have a traveler and a horse and the fall of
the sheet has to lead forward to a turning block close to the tack. It's
tempting to sheet it with the standing end of the sheet on a deck padeye to
oneside, up through a block on the boom, down to a turning block across the
deck from the standing end and so aft.... (this has certain conveniences,
which he here discusses) ...A good many cruising boats were, and some still
are, rigged this way. No racer ever was because the arrangement doesn't hold
the boom down.The sail twists, falls off at the top, draws badly and doesn't
help the mainsail. Its a bad trad off and not worth it even on a cruiser.
... "(and has certain inconveniences, which he then discusses)
As shown on his cartoon, the it is not clear that the jib is attached to the
boom only at the clew, but all the (few) examples I've ever seen were so
rigged, and I'm not sure it is physically (geometrically) possible to do it
otherwise. The gooseneck or whatever of the boom is fixed a bit abaft of the
tack. The sheet runs down to the end of the boom to a block on the horse,
then up to a block on the boom (in an effort from keeping the sheet from
snagging on the mooring bits, etc.) and forward to a point that can't be
discerned, but is presumably just aft of the "gooseneck", to pass around a
block and aft. He says the principal reason for rigging these boats so was
that the crews found having to tend both the running backstays and the jib
sheets as being more work than most crews wanted.
Incidently, the boomed jibs shown in Bolger's cartoons in 100 SBR all
have their forward ends fixed quite close behind the tack of the jib. I have
seen a boat or two with the goosenecks set quite a bit farther aft and on one
occassion received a learned lecture on the virtues of such an arrangement -
something to do with the jib setting "fuller" when the sheet is eased. I
suspect that the rig might be made to work well if carefully enough thought
out - but would require rather sophisticated dealing with sail-cut, horse
width, sheeting angles, etc. I does seem to me that the problem with the
sheet catching on excresences on the fore deck when rigged as Bolger suggests
is the better practice could be avoided by making the boom hollow and running
the running part of the sheet down the hollow interior.
2) Rig #27 "Cat with jib (cat-sloop) shows a jib secured by a pair of battens
bolted through the sail approximately perpendicular to the headstay running
to the clew. Bolger does not think it an appropriate rig for any seagoing
boat because of the danger (inevitability?) of kinking and fatigue fracture
of the head stay.
I would have said that the problem with boomed headsails is the same as
with boomed mainsails: the boom flies up when the sheet is eased. It is
reasonably easy to get a good sail shape for beating, but not so easy for
off-the-wind sailing. For mainsails, the cure is a boom vang (or a sprit boom).
In 100 Small Boat Rigs, Mr. Bolger does discuss the pros and cons of
several options about the sheeting arrangements, and it may be worth your
time and money to get a copy (now "103 Small Boat Rigs", I think). I would
note in passing that many production boats, Cape Dory for one, use a method
that is cheap and not prone to jamming at the expense of sail shape. Island
Packet has gone to a Gary Hoyt-style bent boom than functions as jib boom
and boom vang in one. I think that a vanged boom would not be too hard to
arrange if you put your mind to it. Freedom uses CamberSpar, a variation of
the sprit boom, that appeals to me if the jib stay is not required for the
safety of the mast.
'Best' in this case depends on the layout of your boat, how much crew you
sail with, your personal trade-off among sail shape, money, tolerance of
jams, etc.
Peter
with boomed mainsails: the boom flies up when the sheet is eased. It is
reasonably easy to get a good sail shape for beating, but not so easy for
off-the-wind sailing. For mainsails, the cure is a boom vang (or a sprit boom).
In 100 Small Boat Rigs, Mr. Bolger does discuss the pros and cons of
several options about the sheeting arrangements, and it may be worth your
time and money to get a copy (now "103 Small Boat Rigs", I think). I would
note in passing that many production boats, Cape Dory for one, use a method
that is cheap and not prone to jamming at the expense of sail shape. Island
Packet has gone to a Gary Hoyt-style bent boom than functions as jib boom
and boom vang in one. I think that a vanged boom would not be too hard to
arrange if you put your mind to it. Freedom uses CamberSpar, a variation of
the sprit boom, that appeals to me if the jib stay is not required for the
safety of the mast.
'Best' in this case depends on the layout of your boat, how much crew you
sail with, your personal trade-off among sail shape, money, tolerance of
jams, etc.
Peter
I've always thought the poblem with boomed jibs is the lack of an easily
adjusted out haul to control draft. Again, I've always wondered if a light
wishbone boom might be more self adjusting for draft.
Rennie
adjusted out haul to control draft. Again, I've always wondered if a light
wishbone boom might be more self adjusting for draft.
Rennie
>From: "Foster Price" <foster.price@...>______________________________________________________
>Reply-To:bolger@egroups.com
>To: "'bolger@egroups.com'" <bolger@egroups.com>
>Subject: [bolger] Boomed Headsails
>Date: Mon, 21 Feb 2000 14:04:53 +1300
>
>Hello Guys
>
>I am thinking of adding a boom to the jib of my (non-Bolger) 23' Double
>-ended keeler.
>
>I don't have a copy of Bolgers 100 Small Boat Rigs ( nor does my local
>library) so I would be very interested to see what he thinks about them in
>general.
>
>What do others think, do they reduce the efficiency of the headsail, what
>is the best method of rigging them, does anyone use them in combination
>with a headsail that reefs?
>
>My thoughts are to use the system that Commodore Munroe used on the
>"Presto" class boats (as written up in Gilpins book).
>
>This I understand to be:
>-Longish Boom set on a fore/aft slide on the bowsprit
>-Jib attached to the boom at the clew only
>-Jib fitted with downhaul
>-Boom fitted with inhaul
>
>Another idea I wish to explore is wether the slide for the boom could be
>replaced by a telescoping boom (same as a whisker pole) and actually double
>as the whisker pole when using the Jib or Genoa going downwind.
>
>Regards - Foster Price
>Southland, New Zealand
>
>PS - One Nil to us, four to go
>
>
>
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>
Hello Guys
I am thinking of adding a boom to the jib of my (non-Bolger) 23' Double -ended keeler.
I don't have a copy of Bolgers 100 Small Boat Rigs ( nor does my local library) so I would be very interested to see what he thinks about them in general.
What do others think, do they reduce the efficiency of the headsail, what is the best method of rigging them, does anyone use them in combination with a headsail that reefs?
My thoughts are to use the system that Commodore Munroe used on the "Presto" class boats (as written up in Gilpins book).
This I understand to be:
-Longish Boom set on a fore/aft slide on the bowsprit
-Jib attached to the boom at the clew only
-Jib fitted with downhaul
-Boom fitted with inhaul
Another idea I wish to explore is wether the slide for the boom could be replaced by a telescoping boom (same as a whisker pole) and actually double as the whisker pole when using the Jib or Genoa going downwind.
Regards - Foster Price
Southland, New Zealand
PS - One Nil to us, four to go
I am thinking of adding a boom to the jib of my (non-Bolger) 23' Double -ended keeler.
I don't have a copy of Bolgers 100 Small Boat Rigs ( nor does my local library) so I would be very interested to see what he thinks about them in general.
What do others think, do they reduce the efficiency of the headsail, what is the best method of rigging them, does anyone use them in combination with a headsail that reefs?
My thoughts are to use the system that Commodore Munroe used on the "Presto" class boats (as written up in Gilpins book).
This I understand to be:
-Longish Boom set on a fore/aft slide on the bowsprit
-Jib attached to the boom at the clew only
-Jib fitted with downhaul
-Boom fitted with inhaul
Another idea I wish to explore is wether the slide for the boom could be replaced by a telescoping boom (same as a whisker pole) and actually double as the whisker pole when using the Jib or Genoa going downwind.
Regards - Foster Price
Southland, New Zealand
PS - One Nil to us, four to go