In article , DSK
wrote:
But it does add weight down
low, and it's relatively cheap... if it gives the boat enough life span
to last out your likely tenure of ownership, why not?
Peter Wiley wrote:
Yeah, if you want to look at it like that, fair enough. It makes me
uncomfortable tho.
It would me, too. But as a practical matter of boat-keeping, you cannot
make everything perfect.
Doug, there's nothing wrong with the junk rig on that hull and I don't
understand why you think there is. It was designed for the rig.
I just don't like junks. They have a lot of windage,
True.
proportionately
more weight aloft,
But why is this bad? Taken to a logical conclusion, you're saying the
less weight aloft the better.
From a standpoint of stability & speed, that's true. But I agree with
you that there are other factors.
Yeah. Like, taken to its ultimate, you have no rig at all and end up
with..... a tug boat!
... In practice this has been shown to be a
bad assumption. Weight aloft damps out roll, extends roll period and
provides more inertia to resist rolling over. I agree that too much
weight aloft isn't going to be good either, but the implication that
more is bad doesn't hold up.
Depends on what you want the boat to do. Roll damping is good, but
weight aloft also hurts LPOS.
Don't I recall some data from the Fastnet fiasco of some years ago WRT
lack of weight aloft as a contrib factor to rolling over?
I don't really have any feelings pro/con about the looks. They're
different is all. As to pointing, true but so what? It's not designed
as any sort of racing vessel. That hull form won't point as high as a
fin keeled sloop no matter what rig it has. It's not designed for it.
Dunno about pointing, it's true that it's not going to climb to windward
like a 12-Meter no matter what rig you put on that hull. But I'm
uncomfortable with a boat, no matter how "cruisy," that does not go to
windward pretty well,
So - what do you mean by 'pretty well'? You're an engineer - give some
figures.
or (as many cruising boats) will only make ground
to weather at all in ideal conditions. Too easy to get trapped, and too
dependent on the engine (odd as it may sound for a tug boat owner to say
that).
Yeah. But what makes you think this criticism applies ot all or even
most junk rigs? I think you've taken assumptions and treated them as
facts. There are at least 2 examples - the Colvin Gazelle design and
the Benford dory - that can & do go to windward in somewhat less than
ideal conditions. The first Gazelle was built and sailed for some years
sans engine. The Hill's dory ditto.
What's worse, many boats that have difficulty getting to windward are
ulso unhandy on the helm & reluctant in stays. It's a vicious circle.
OK, true. But do you think either of these things are peculiar to or
universal amongst junk rigs? If so, why? At least 2 people with junk
rigs disagree with you. Where is the basis for your implication that
junk rig vessels are
a) difficult or impossible to sail to windward
b) unhandy on the helm and
c) reluctant in stays.
It might be a vicious circle, but you haven't demonstrated that it is a
universal characteristic of junk rigs, and people with in excess of
100,000 miles sailing them disagree with you. I'm open to argument, but
all you're doing is making assertions, and those without reference to
any recognised authority.
But it's
dependent on the cutting edge of 17th century technology. With just a
teensy bit more budget,
Like somewhere in the vicinity of 10X, I'd venture to say......
Not at all. Part of what I'm trying to say is that all the stuff to
build a rig like that can be picked up 2nd hand or free, if you don't
mind spending the time hunting around. Around any recreational sailing
area, it's easier to find parts for than a junk rig.
Doug, almost *any* rig can be picked up 2nd hand or free, if you don't
mind spending time hunting around. I really can't see this is relevant.
I think the people who extol the junk rig are very full of descriptives
like "no rig easier to control" when that's not really quantifiable...
and the rig they are extolling is also "easier to control" because
there's less of it.
So? Still a valid point, if you agree that the objective of a rig is to
get you from A to B in a reasonable time. 'Reasonable' is subject to
definition but I really don't think 140 mile days for a cruising boat
is bad.
I also wonder how many of them have much experience
with modern rigs... the same crowd seems very down on roller furling &
self tailing winches.
Another point is that "easy to control" and "inexpensive" are the junk
rigs *only* two virtues.
How about long lived, difficult to damage and easy to repair?
On what point(s) of sailing? Upwind, maybe - if you care. IIRC Colvin
said the rig points as high as a Marconi rig but made more leeway.
That may have been true, given less effective underwater foils, back in
the 1960s.
I think we're back to the draft factor again. You're cherry picking. If
you put a highly efficient to windward rig on a shoal draft cruising
vessel, it ain't going to work too well. Keep the engineering params in
mind - it's a cruising vessel with shoal draft for gunkholing.
Demonstrate, within these constraints, your assertion that the Marconi
rig will outpoint the junk rig. I'm happy to be convinced as I don't
know from personal experience myself.
... OTOH
it tended to run away downwind as the sails could be set wing & wing
easily, without the main blanketing the fore.
Sorry, I don't think that a heavy junk-rigged schooner
What do you define as 'heavy'? What displacement?
is going to "run
away" from any but the pokiest marconi rigged boat, and that without any
flying sails set.
... You could also sail by
the lee without any dramas
A matter of skill on the part of the helmsman
... and a gybe was also pretty drama free as the
balanced lug damped out the motion when the sails swung across.
Now that much is true. Add that to the list of virtues... "easy to
control", cheap, and easy to gybe.
... Short
tacking up a channel was effortless.
So is a gaff cat, or cat ketch, or sloop with no jib or self-tacking
jib... and a sloop with a small jib is not difficult.
True. Now, how do those rigs compare to the junk rig in terms of sail
area set?
I simply do not believe that you can build a fully battened Marconi rig
for anything like the price of a junk rig.
Why not? Go scrounge around a boat yard nowadays, you'll find lots of
2nd hand parts & components for such a rig... and darn few junk rig
parts.
Ummmmm, that might be because there are damn few - I hesitate to say
none - specific junk rig parts. Feel free to correct me by listing
some. Therefore, it's a wash at best.
I just did a Google search for used sail batten cars. Guess how many
sites selling them popped up? Nice round number........
Of course, if you're shopping at the farm & truck supply place,
then maybe you can cobble together something, and it won't cost much...
but then neither will the boatyard cast-offs.
... Nothing I've ever read
indicates that you can even get close. Are you going to have the same
height mast(s)? If so, where's the gain in sail area?
In staysails & flying sails,
Wellllllll, the Gazelle has a jib and a fisherman as well as its 2 junk
sails. So no gain at all, then.
and the Marconi sails are more efficient.
Doug, Marconi sails are more efficient *to windward*, and only then if
in very good condition. As soon as they get saggy & baggy, the
efficiency goes to hell. On reaching & running the tall Marconi rig is
inefficient compared to almost anything else. I can't find any
authority that says different. Quote me one.
Quoting from:
http://www.kastenmarine.com/gaff_rig.htm
It is well known that higher aspect sails produce greater lift when
close hauled.* It not so widely known however that high aspect sails
stall much more readily as the angle of attack widens. As A/R gets
higher, sails get less and less efficient at pulling when anywhere but
close hauled.
For racing, where windward performance is of prime importance, it has
been shown that an aspect ratio greater than 6 is of little use on
monohull racing craft.* An appropriate range will be an A/R of from 4
to 6.
A polar diagram showing lift vs. drag plotted for sails having the same
area but differing aspect ratios very graphically shows that the
favored lift / drag position is quickly handed off to shorter and
shorter rigs as a sail is eased. If you would like see this data
graphically presented, please have a look at the Aero-hydrodynamics of
Sailing by Marchaj, p. 444, Fig. 2.138.
A study of this data shows that the most favorable aspect ratios for
ocean cruising, where all-around performance is the goal, an aspect
ratio from 2.5 to 3.5 is very appropriate, with an approximate upper
limit of around A/R 4.* Naturally, these are not "hard" boundaries,
only guidelines.* In most cases, a compromise is struck in
consideration of the times inevitably spent sailing to windward.
In the data presented by Marchaj, angle of incidence of the sail is
plotted against lift vs drag.* A sail having an A/R of 6 performs
exceedingly well at an angle of attack to the apparent wind of 10
degrees, where lift divided by drag (L/D) yields a ratio of around
8.5.* At 10 degrees, a sail with A/R 3 has an L/D ratio of 6.5.* At 15
degrees, the A/R 6 sail has an L/D ratio of 4.47, and the A/R 3 sail
has an L/D ratio of 4.5.* At 20 degrees, the A/R 6 sail has an L/D
ratio of 2.7, while the A/R 3 sail has an L/D ratio of 3.3, and so
forth.* By the time an angle of attack of 30 degrees is reached, the
favored position is handed off to a sail with an A/R of 1...!
The salient point is that extremely high aspect sails are not "bad"
sails, they are just not a requirement for general ocean cruising,
where it is rare to be sailing dead to windward.* When required to do
so, sails with an A/R of from 3 to 4 will perform quite well when just
eased off a few degrees.
======================================
Do you disagree with this?
Look, we're referring to cruising boats here, as that's what the
Gazelle is. That means few people doing boat handling for up to 30 days
at sea. Every extra sail you take means that much less space for other
gear & supplies. Seems to me that you're fixated on windward sailing
ability to the detriment of other factors.
But with less weight and less windage aloft, there's no reason to not go
higher. In fact a higher rig of the same weight provides more
damping.... so there you go!
... If not, how much
higher are you going to go and how do you propose to brace the mast(s)?
Adding spreaders and more rigging wire costs money, increases the rig
loadings and requires either higher tensile strength materials or
thicker materials to gain the needed strength.
True enough, and those materials are very common & easy to find.
............. at a price. I'm in the marine engineering business, I know
what stuff costs.
As I said, if one is determined to use 17th century technology, then the
junk rig makes a great choice.
And if you're determined to use 21C technology, that's a great choice.
For your chandler. If you have deep pockets. For cruising vessels,
there's a point somewhere in between that's appropriate. If you're
cruising from marina to marina and have spare everything a phone call
away, one level of equipment might be appropriate. If you're operating
in distant waters, another might be better. Would you put rod rigging
on a cruising boat under all circumstances? If not, why not? It's more
efficient in terms of reduced stretch.
....The batten cars cost a
hell of a lot more than the junk sail lacing. The sailcloth for a
battened Marconi sail needs to be of a lot higher standard than for a
junk sail. Etc.
In other words, you want to stitch burlap bags together and hang it on a
rig assembled from odds & ends out of a discount plumber's supply? Be my
guest... I won't even fuss when you brag about how easy it is to control!
Come off it. Do you need mylar sails for cruising on a Marconi rigged
boat? They've got better material specs than Dacron. If you're not
using mylar, does that mean you're using the equiv of burlap? How about
rod rigging instead of 1x19 s/steel? Or galv wire instead of s/steel
wire?
That bit of argument is reminiscent of Bobsprit. When you can't refute
the point, go for the exaggeration and hope nobody notices.
... I point out that if you increase the rig height then
you're most likely going to have to start reefing in lighter air due to
the extra leverage aloft, unless you also increase ballast/draft as
well. There goes the shoal draft gunkholing ability.....
If the boat *sails* well in relatively light air, thent what's the issue
of having to reef? As long as the boat sails well when reefed, and the
reef can be taken in or shaken out without too much labor ...and with
the solid vang & lazy jacks, it's a matter of easing one line and
pulling another, while the sailing characterisitics remain pretty much
the same...
Yeah, ok, point - there's no real difference.
This particular vessel (Migrant) has been recorded as doing consistent
140+ mile days cruising over many passages & many years.
That's pretty good. OTOH it's also a big boat. 140 mile days on a 40' +
LWL is comparable to 90 mile days with a 32' LWL.
Except it's 35' LWL, 42' LOD IIRC. I'd need to check the exact figures
but that's close.
How many production boats have got to that number of
hulls in the water?
Only the ones that have been very successfully marketed... as have the
junk rigs!
Ah. Damn few to none, then, that you can find.
Weekend is here and I'm going sailing as I only have 4 weeks left in
this year. This can wait till next week or forever, depending........
PDW