J92s, Hull#30

[jwhj92s]

Hello all,

I just purchased the J92s, hull#30. We are sailing on Lake
Pontchartrain, along the Gulf Coast. This boat is very new to me, as
I used to sail a J30, #445, which was lost in Katrina. I have read
everything possible on the internet, including the rig tension numbers
at Key West. We are consistently racing against J35, Evelyn 32,
Hobie33, and a J92. We finished second in our first 5 race series to
the Evelyn 32. We have tanked some races and had moments of
incredible boatspeed, we are looking forward to some consistency. Any
pointers to shorten our learning curve would be more than greatly
appreciated.

Our conditions are generally 5 - 10 with light chop. Any more rig
tensiion numbers? Tips on pointing? Tips on not losing the helm
during a power reach?

Having alot of fun so far and looking forward to imersing myself in
the local sailing scene once again.

John

[Gene Cloutier]

John,

Congratulations on your new purchase!  The J92 is a lot different boat than the J30.  I own a J92 on Lake Champlain in VT where we race at a phrf of 105 vs. Pearson 37's (105), c&c 99's (105), a number of J29's fractional (114) and masthead (111) and a couple J30's too.  I think the biggest change you will find is figuring out the angles of sailing an asymmetrical.   The biggest piece of advice I can give you is you need to sail these boats with big s turns.  As far as rig tension, Lake Champlain has similar conditions with mostly 5 -10 with some occasional 15 - 20.  If I remember correctly, my rig tension is generally 38 for the uppers and 26 for lowers.  If it is really light I take 2 turns off the lowers and leave the uppers.  In the windier conditions I add 3 turns to the base of lowers and 2 turns on the uppers.  However, I am sure this depends on the shape of your sails.  

Gene

SurRealEscape #43

[Todd Aven]

I wonder how much we can compare rig tension between the J/92s and the
J/92 classic? The geometry is significantly different with the outboard
placement of chainplates and deeper sweep on the spreaders.

For what it's worth, in the same wind conditions I had (top to bottom)
37/38/34 on my classic.

[Todd Aven]

As far as pointing upwind, you have to watch out because the boat's
foils stall pretty easily. You'll probably feel horribly underpowered in
5-10 with the non-overlapping jib. Keep the bow down and the sails fat,
or your speed will fall off the proverbial cliff. Never ever try to
point as high as the J/35.

For power reaching, the "s" has a deeper, finer rudder than the classic.
If you can react quickly enough, when you feel the rudder start to lose
it's bite pump the tiller to windward quickly and grossly a couple of
times to break the cavitation and help re-attach flow to the foil

Cheers,
Todd Aven
J/92 #14 Thin Man

[Ragtime!]

Congrat's John.

I wondered where that boat went - it sounded like it was set up well.
I'm curious to know how you like the NKE instruments. I'd like to get
an NKE autopilot someday and would probably need to change out my
Raymarine instruments.

You might try getting ahold of Kenny Kieding with The Chandlery in
Santa Barbara, CA. He's responded to my e-mails in the past. Kenny
put together Dr. Laura's J/92s (#55) and raced it successfully in
generally light Southern California conditions. They did so well that
by the time they sold it, the rating was all the way down to 84!

Kenny told me that getting a properly-cut jib is critical. As an
aside, I learned that on a non-overlapper like the 92s, the 108% jib
is called a #1.

The other person to contact is Jeff Johnstone. Before Dr. Laura
bought #55, Jeff raced it at Key West (2007?) Jeff is the guru for
either flavor of 92.

Have fun and stay in touch!
Bob J.
Old style J/92 #18 (What's this "Classic" stuff?)

[jwhj92s]

Thanks for all the replys guys.

I don't think the classic 92 and the 92s can sail with the same rig
tensions. I was told the S likes a straight mast, very little
prebend, don't know if the classic is the same. I appreciate your
numbers and will consider tightening up my rig.

As far as the tiller pumping goes, my arms were worn out after a race
in which the we set the AP chute in 12 knots to go downwind; halfway
to the finish the wind shifted forward and increased to 18-20.
Pumping only prolonged the inevitable. Don't know if flying the
reacher would have helped.

Thinman, are you a classic or an S? I think one of the other
differences between the two are the foils, both keel and rudder are
alot different.

On to the NKE instruments. When we get them calibrated correctly, I
will like them; until then, they supply me with false info which is
not very helpful. The compass is 20 degrees off between 20 and 180,
only. Siebe at NKE says it has a fork in it, and I should send it
back. The apparent wind indicator has also eluded our attempts to
calibrate it according to the book. Boatspeed, depth, and wind speed
looks good. When everything is working, I forsee a need for three
more dispays. I am trying to connect my Garmin GPS via an NMEA
cable. I got the connection but the data it chooses to display
doesn't help. I was looking for my magnetic heading, which I get, but
it alternates every 2 or 3 seconds with speed over ground. Havn't
figured out how to get only my course over ground.

I'll look for contact info on Kenny Kieding, sounds like he had much
success with the S.

Looking forward to sailing the boat, and learning what it takes to
make her go; again, thanks for the info. Does the classic 92 have
three sets of shrouds? I set mine to 35-32-28, top to bottom but have
since changed them many times.

John

[jwhj92s]

Sorry Bob, I meant to say "Old Style", classic should be reserved for
wooden hulls with full keels. :-)

How about "The Throwback 92"?

John

On Nov 11, 12:00 am, "Ragtime!" <bobsail...@gmail.com> wrote:

[Todd Aven]

On Tue, 11 Nov 2008, jwhj92s wrote:

> I don't think the classic 92 and the 92s can sail with the same rig
> tensions. I was told the S likes a straight mast, very little
> prebend, don't know if the classic is the same. I appreciate your
> numbers and will consider tightening up my rig.

I don't know that I buy the bit about the S liking a straight mast. Your
sailmaker should have the final word on your rig setup.

Thin Man is a J/92 (#14) and my main is a North 3DL. It is cut for a
significant amount of pre-bend, and I have about 21" of rake as well which
probably has a significant effect on how the mast bends for a given shroud
tension.

>
> As far as the tiller pumping goes, my arms were worn out after a race
> in which the we set the AP chute in 12 knots to go downwind; halfway
> to the finish the wind shifted forward and increased to 18-20.
> Pumping only prolonged the inevitable. Don't know if flying the
> reacher would have helped.

What was your true wind angle? If the wind was really 18-20, I would say
anything tighter than about 130 is jib-and-main territory. I may have
polar tables from Jeff for the 92s. If I can find them, I'll post them
here.

> On to the NKE instruments. When we get them calibrated correctly, I
> will like them; until then, they supply me with false info which is
> not very helpful. The compass is 20 degrees off between 20 and 180,
> only. Siebe at NKE says it has a fork in it, and I should send it
> back. The apparent wind indicator has also eluded our attempts to
> calibrate it according to the book. Boatspeed, depth, and wind speed
> looks good. When everything is working, I forsee a need for three
> more dispays. I am trying to connect my Garmin GPS via an NMEA
> cable. I got the connection but the data it chooses to display
> doesn't help. I was looking for my magnetic heading, which I get, but
> it alternates every 2 or 3 seconds with speed over ground. Havn't
> figured out how to get only my course over ground.

I know it's not helpful, but I have to give a shameless plug for Nexus
NX2. I installed a complete new system, and calibrated the speedo against
a handheld GPS in calm waters (maybe 30 minutes of effort). The system has
given me very accurate information, especially TWA and TWD, for the entire
season. Outstanding system and easily integrated with existing GPS and
laptop.

> Does the classic 92 have three sets of shrouds? I set mine to 35-32-28,
> top to bottom but have since changed them many times.

Yep, three sets. Don't forget to work on ideal headstay length vs. wind
speed.

Cheers,
Todd

[jwhj92s]

Todd

My boat came with a fresh set of UK sails. Very nice looking sails;
main, #3(class jib), #4, storm jib, AP chute, and a reacher chute.
The main, #3, and reacher can be viewed in the Files section. My
local sailmaker is a North man. We are talking with him about a light
air class jib. When he sailed with us, he liked the sails and we won
our race, naturally. I will get more input from him on my rig
tensions as they relate to the cut of my sails. Are you happy with
the performance and longevity of your North 3DL's??

I didn't have my true wind angle up, but judging from the windex, we
were sailing with the apparent wind close to 90 ocassionally. This
race was won by the J92OS(old style), we watched him broach maybe 5
times just slightly ahead and to windward of us. We attempted to do a
leeward takedown and finish under jib, but the takedown did not go
very well, to say the least. I would LOVE to see the polars for the
S. I am sailing with the OLD SCHOOL polars right now, as a reference.

My headstay is currently very loose, about 6" of sag. I find, even in
lighter air, we will point higher with a little backstay on. The
current lenght was set by John Kolius of KO Sailing.

Thanks again for the info, looking forward to seeing some pics of Thin
Man.

John

[Ragtime!]

On Nov 11, 8:44 am, jwhj92s <j...@diversifiedfoods.com> wrote:

"I would LOVE to see the polars for the S.  I am sailing with the OLD
SCHOOL polars right now, as a reference."

John, I just uploaded a little ditty I created a year ago for our
local PHRF committee. It's an Excel file over on the Files page. It
was based on some pretty solid data. I was considering buying your
boat and wanted to see how our committee would have rated it.

More later (when I'm not supposed to be working).

Bob J.

[Todd Aven]

I have the J/92s and J/92 IMS VPP tables and will upload them tonight when
I'm not under the corporate yoke.

[Ragtime!]

On Nov 11, 8:44 am, jwhj92s <j...@diversifiedfoods.com> wrote:

"I would LOVE to see the polars for the S.  I am sailing with the OLD
SCHOOL polars right now, as a reference."

I'm not sure how to do a link here - this guy has some S-type tuning
data:

http://www.furkolkjaaf.net/the_boat.html

I haven't compared his numbers to anything but maybe it will help.

Bob J.

[jwhj92s]

So what was the outcome? The data shows two boats that are very close
in performance even though one has smaller, more manageable sails. I
know it also shows the S to be a wee bit faster, moreso upwind than
down. We have yet to realize these gains and are working diligently
on sailing the S to its' potential. Our PHRF number is 99, the OLD
SCHOOL is 105. It's hard to understand that a similar boat, with less
sail area, and more displacement is faster. I know the foils are
substantially different, and I love the larger cockpit but .........
So why did you opt to not buy the S? I considered buying an OLD
SCHOOL, but the ones I looked at had some problems. The newer
constructed S, had more appeal to me, I only hope I can learn to sail
her efficiently.

John

[jwhj92s]

Wow!! That's alot of data. The two files are both for the OLD SCHOOL
92, unless I'm reading them wrong; naturally, I would be more
interested in seeing the S numbers, although I think the performance
of the two boats are very close.

John

> > SCHOOL polars right now, as a reference."- Hide quoted text -
>
> - Show quoted text -

[Todd Aven]

Sorry, I screwed up and gave the same link for both models. The link for
the J/92s should be this:

http://www.j92.org/J92s-vpp.doc

Unlike the VPP I have for the J/92, it did not come with a descriptive
header so I can only assume that it is based on the "class" sails.

Cheers,
Todd

[jwhj92s]

I spoke to Ken at The Chandlery yesterday. He said the boat liked
alot of mast rake, so much so, they lengthened the headstay, shortened
the backstay, moved the step forward and recut the main to keep the
boom out of the cockpit. I was told the S liked a straight mast, no
prebend by more than one respected sailor. Ken's boat won enough
races to be rated 84, maybe he was onto something, most of the J boats
I sailed in the past liked prebend. I will probably readjust my rig
to setup as much prebend as the stock rigging will allow and see if I
gain any advantages. Any thoughts?

John


On Nov 11, 12:00 am, "Ragtime!" <bobsail...@gmail.com> wrote:

[Todd Aven]

Put a small mark on your boom half way out, on both sides. Use this mark
as the position for your camera. Take photos of your sail upwind in
"normal" conditions and make a note of the conditions and rig settings.
Change the settings and take more pictures in the same conditions. Compare
the pictures and decide which shape you like better. Later, rinse, repeat.

Cheers,
Todd

On Wed, 12 Nov 2008, jwhj92s wrote:

[jwhj92s]

Sounds like a plan.

Thanks

> > and see if I gain any advantages.  Any thoughts?- Hide quoted text -

[Ragtime!]

Hi John - responses below:

> So what was the outcome?

Since I didn't proceed with the purchase I didn't submit the paperwork
to our PHRF committee. They aren't keen on rating hypothetical boats.

> The data shows two boats that are very close in performance

My submission would have included head-to-head race results for 6-8
boats from the UK; I think the results were from SpiQuest (I'll look
that up again). Over there, the J/92 races under IRC with 135-140% LP
headsails and most of the time corrects out ahead of the S-type. I
planned to argue for an equal PHRF rating between the two designs and
probably would have ended up with the 6 sec./mile spread recommended
by J/Boats (basically where you are at 99).

> So why did you opt to not buy the S?

If I didn't already have my 92 I would have bought it (or #55). I
decided that it would not have been enough of an upgrade to justify
the "transaction costs." My boat is fully equipped for offshore
singlehanded racing and has a bewildering inventory of newer sails and
offshore gear. I might have been able to use some of my kites on the
S-type but that's about it. Also Ragtime! is pretty cherry - I know
what you mean about some of the used 92's that have come on the
market.

Regarding tuning, I run at full rake around here. The Hawaii and
coastal races are mostly downwind so I tip the mast full forward for
those (to improve separation between the main and kite). I have an
extra spectra section in my backstay tackle to deal with the
difference between the two modes. The headstay has actually been
shortened slightly to help with sag in our big breeze here in S.F. My
mast is tuned with zero prebend and the main is designed accordingly.
As I'm sure you know, on these fractional rigs you have to have the
main cut for the amount of prebend in the stick.

My last main was designed for my old setup (with some prebend) but I
couldn't get it flat enough without screwing up its shape. It is a
great light-air sail and has full PHRF roach, five battens, etc. The
new main is flatter, four battens, deeper offshore reefs and less
roach.

I also have running backstays - I only use them beating out into the
ocean in chop when I want lots of headstay tension but a powered-up
(not too flat) main. The 92 is notorious for headstay sag and poor
pointing with the #3. I think I have resolved most of the problem now
with the newer rig setup and sails, and the use of inhaulers with the
#3.

Bob J.

[jwhj92s]

Thanks for the informative reply Bob. The price difference between a
worn out, 10 year old J92 was not enough for me to not purchase the
new 92s. I too believe the ratings should be the same or even closer,
who knows, by next year our results may be all the proof the GYA needs
to raise my rating; I hope not though. Most of the 92s I looked at had
things added to the deck, which I know were not bedded properly, with
the evidence to prove it. I will think LONG and HARD before I add
anything to the deck of my S. Although I would like a small cam cleat
to keep the spin sheets out of the water when sailing upwind.

I can't imagine sailing/racing this boat alone. Sometimes eight hands
are not enough for us. You have my full respect for your singlehanded
accomplishments.

[jwhj92s]

Thanks a bunch Todd. Those files are full of great info. I'm sure
the S must be with the class jib, that's the only one it can fly, no
overlapping jibs possible. We do have a jib-top, which we fly between
beam and close reaching.

John

> >> - Show quoted text -- Hide quoted text -

[Ragtime!]

On Nov 13, 6:58 am, jwhj92s <j...@diversifiedfoods.com> wrote:

> I will think LONG and HARD before I add anything to the deck of my S.  Although I would like a small cam cleat
> to keep the spin sheets out of the water when sailing upwind.

With the cored deck you have to take the extra time to do it right -
that's for sure. I found that in some cases I could use existing
hardware for different purposes, or at least use one or more of the
existing holes. For example, to clean up the foredeck for
singlehanding, I moved the roller furling line out to the stanchions
and the on-deck sprit control line below (like on the newer boats).
The freed-up cams on the sides of the cabin trunk became the cams for
new adjustable genoa leads. I changed out the single deck organizers
for stacked ones, requiring no new holes. I installed a windward-
sheeting traveler and the old traveler cams are now used for the main
fine-tune, etc.

I would go ahead with the extra cams for the spinny sheets - the first
time a sheet ends up around the SailDrive, you'll be glad you did.
(Just pot/redrill the holes, etc. - do it right and you'll have no
core problems.)

> I can't imagine sailing/racing this boat alone.

On short sausage courses it would be hard, but that's not what we do.
These boats are GREAT for it - once you get a good autopilot and start
racing solo on longer courses, it is hard to go back. We raced three-
up last Sunday in a buoy race and I was completely disoriented and off
my game.

Your sails look great in the photo. One of my concerns about #30 (and
especially #55) was that I would have to get flatter sails right away
for our conditions but after seeing your photos, I'm not so sure - I
think your main is flatter than mine.

It's crazy (to me) to see eight people on the boat though!

[Ragtime!]

On Nov 13, 10:11 am, "Ragtime!" <bobsail...@gmail.com> wrote:

> I installed a windward-sheeting traveler and the old traveler cams are now used for the main fine-tune

Correction - I later moved all four cams lower to increase leverage
for pulling in the controls. The yard did a nice job of making the
old holes disappear.

[jwhj92s]

Reference my flat sails.

The wind was up pretty good for that race. It was the Pink Ribbon
Regatta, you may have noticed the female at the helm, the large pink
bra connected to the lifellines, among other odd things that earned 3
point credits each, to our rating. I believe we ended up sailing with
a 285 PHRF rating. The wind was blowing about 15 - 20 and required
flattened sails and a dropped traveler, the downwind run was fun, that
is the other picture I posted. That is about as flat as those sails
will get, they do power up nicely with things eased off a bit. BTW,
eight people on a beam reach in 20kts is alot of fun!!! I just have
to make sure we end up with the same number we started with. :-)

John

[furkolkjaaf]

Hi John,

I have my 92s since this spring, and have played a little with rig
tension but honestly do not think to have figured out what is fast and
what not.
My current settings are high/intermediate/lower = 34/16/21 and where
I'm struggling the most is in light and very light conditions,
especially with chop.
I would like to loosen things up furtherly, but I'm little concerned
for mast stability. I have the "standard" mast rake (as per builder's
set up) but not sure at all this is the fastest. I haven't been able
to find a sailmaker down here who really has a clue on how to get this
boat optimized.

Cheers from Italy
Max
Furkolkjaaf #81

[furkolkjaaf]

On 12 Nov, 16:48, jwhj92s <j...@diversifiedfoods.com> wrote:
> I spoke to Ken at The Chandlery yesterday.  He said the boat liked
> alot of mast rake, so much so, they lengthened the headstay, shortened
> the backstay, moved the step forward and recut the main to keep the
> boom out of the cockpit.  I was told the S liked a straight mast, no
> prebend by more than one respected sailor.  Ken's boat won enough
> races to be rated 84, maybe he was onto something, most of the J boats
> I sailed in the past liked prebend.  I will probably readjust my rig
> to setup as much prebend as the stock rigging will allow and see if I
> gain any advantages.  Any thoughts?
>
> John

John,

this guy, Ken, sounds like he's a guru of the 92s...
How much rake are we talking about ? There must be some precise data
probably...
One thing I also was wondering is how to move the mast step forward
since my boat has a sort of "hole" on the floor where the mast is fit
into, so apparently no chance to move it...How is it on your boat ?

I also take this opportunity to say hello to you all J/92 & J/92S
fellows !

Max from Italy
Furkolkjaaf #81

[jwhj92s]

Hi Max

We had our rig much looser than that in a drifter or two. I would'nt
be afraid to loosen things up in light air and see how it affects your
performance. I retuned my rig this past weekend, going with 38-15-22,
winds were 10 -15 for our races. We sailed much better, but were
still beaten by a J-35 and a Beneteau 40.7. The boat felt better at
these settings. I find the slot is very small upwind, and beating to
windward in a chop, is a battle of concentration. How's the weather
in Italy, are you still sailing?

John

> > > John- Hide quoted text -

[James R. Stansbury]

John and all the lucky J92 owners,

I have attached my analysis I did of my boat's mast bend when I was buying new sails for my J92. I spend months trying to tune the rig and came to the following conclusions:

1) Tune mast pre-bend and max-bend to the mainsail cut. My sailmaker found my measurements of my mast bend with various backstay adjustment most helpful. My sailmaker was also interested in the keel profile, which he already had access to.
2) Tune mast rake to the feel of the helm. I raked my mast until I felt just a little weather helm. I did rake the mast too far back to get a feel of how bad the helm could get, then raked it forward until the helm was just right. My mast step base is all the way forward. Mast rake moves the center of effort of the main and jib in relationship to the center of effort (or lift) of the keel. This effect the feel of the helm. I did not need to cut my forestay to find my sweet spot for the helm.
3) The lower shroud tension controls how much your mast will bend and what the arch will look like when applying backstay. Tight lowers will not let the center of the mast bend forward when backstay is applied. I look for lots of nice even bow in the mast when I apply backstay so I can control or flatten the mainsail.
4) Forestay sag is something I could never figure out how to measure. Upper shroud tension seems to control forestay sag when the backstay is slack but adds pre-bend. Increasing backstay does decrease forestay sag but flattens the main with mast bend. Forestay sag is the Achilles' heel of a fractional rig. This is my problem area that I actually tuned the rig to eliminate.
5) I play the backstay very aggressively when the wind is puffy. It really changes the shape of the mainsail more effectively in those conditions that the mainsheet. I see the backstay as a mainsail control line, it just happened to attach to the top of the mast.
6) I made my backstay a 32:1 system with marked increments of adjustments so I can return to an known adjustment. I can pull my backstay over 4" with little effort, but it takes lot of backstay line.

To take my mast bend measurement, I sent a guy up the mast on the spinnaker halyard with a measuring tape. I found the lightest person for the job so not to affect the mast bend. I ran the mail halyard down to the gooseneck and tied a line around the mast and halyard at each black band to pull the halyard against the mast at the bands. With the guy sitting in the bosun's chair at each measurement position at the mast, I adjusted the backstay to each of the nine backstay positions and a measurement was make between the mast track and halyard.

Also, I hope no one is using wire halyards or backstay. They were standard on my boat. I did a weight reduction analysis when I replaced mine but lost the numbers. The weight reduction was dramatic.

Jim Stansbury J92 #27 UBIQUITOUS
240-401-7944

[jwhj92s]

Great info James. When you say you tied a line around the mast and
halyard at each black band, what do you mean?
I can see the main halyard running from top to bottom and the space
between being the prebend measurement, this would change at each
backstay setting. But, if the halyard is tied to the mast, how do you
measure the distance? So, who built your sails, and how do they
work? Any pictures? Sounds like a good plan, the more data you can
give your sailmaker, increases your chances of getting a good sail.
Is the maststep in a 92 adjustable? The S has a fixed postition.
Will these measurements all change if you change your rig tensions?

John



On Nov 17, 10:25 pm, "James R. Stansbury" <jim.stansb...@strickland-

>  J92 UBIQUITOUS Mast Bend.pdf
> 174KViewDownload- Hide quoted text -

[furkolkjaaf]

On 17 Nov, 23:21, jwhj92s <j...@diversifiedfoods.com> wrote:
> Hi Max
>
> We had our rig much looser than that in a drifter or two.  I would'nt
> be afraid to loosen things up in light air and see how it affects your
> performance.  I retuned my rig this past weekend, going with 38-15-22,
> winds were 10 -15 for our races.  We sailed much better, but were
> still beaten by a J-35 and a Beneteau 40.7.  The boat felt better at
> these settings.  I find the slot is very small upwind, and beating to
> windward in a chop, is a battle of concentration.  How's the weather
> in Italy, are you still sailing?
>
> John
>

Thanks John,
weather is still decent here in Italy and we are still sailing up to
end of november with our "fall series".
Generally light or very light air, with occasional days of 15-20
knots.
We'll see how the next weekend will go...
Max

[jwhj92s]

Keep us posted. We sailed the last race of our fall series, this past
Sunday. Next series will be the Sugar Bowl regatta, then the winter
series. We get to sail year round here, although it does get pretty
nasty. I saw alot of videos of you on the Thin Man site, your boat
looks very nice.

John

[James R. Stansbury]

John,

In measuring mast bend, I wanted to measure bend as seen between the mainsail track and a imaginary straight line between the top and bottom black bands on the mast. As the main halyard exits the mast at the top, it over 3" away from the sail track. When the halyard is attached to the gooseneck, it's around 3" away from the sail track. If left this way, I would have an offset in my measurement. I wanted a baseline measurement of 0 both at the top and bottom black band. Therefore, I tied a line around the mast and the halyard to pull the halyard tight to the mast at the top and bottom black bands. This gives my graph and table a baseline of 0 at the two black bands.

With this done, the gap you see in the middle of the mask between the sail track and the halyard with the backstay slack is your pre-bend. If you don't see any gap, you don't have pre-bend. No pre-bend is unusual on a fractional rig. In my measurement table, in the first column is my pre-bend with backstay at position 1 or 0" of tension. I have a pre-bend of 1.75" as measured at the upper shroud.

Mast pre-bend in a fractional rig is created by mast compression caused by tight upper shrouds and relatively loose lower shrouds, which let the middle of the mast move forward as the mast compresses. If your lower shrouds are too loose you will see mast sag or out of column, the middle of the mast bows to the low side, in heavy air and mast pumping in heavy seas. Both are bad.

My loos gauge doesn't tell me when my rig is tuned correctly, it tells me when my port and starboard shroud tension is even. Sighting up the mast along the sail track and seeing a nice straight and even bow in the mast under different wind conditions and seeing the amount of bow controlled by the backstay tensions tell me when my rig is tuned.

Boat speed tells me I'm using my sail control lines (including backstay) to create the right sail shape and draft to match the wind and wave conditions.

The amount of weather helm in my tiller tells me I have the right mask rake. I like a neutral helm.

North built my class sails, and Quantun build my kevlars for PHRF. Your sailmaker should cut you main's luff curve to match your mast bend. My sails are so old picture are useless. My mast step base is adjustable about 1.5".

Between the adjustable mast step and blocking the mast in different positions at the cabin top, and adjusting forestay length, all combine to adjust mast rake. I tried to measure mast rake using the main halyard as a plumb-bob with the boom level to the horizon (use a level). I tried to measure the distance between the mast and the end of the main halyard as it came to rest on the boom. The boat moves around in the slip too much and the measurement was very subjective due to weight distribution of the equipment in the boat (you need to empty the boat).

I found that a fast bottom, a good hand on the tiller, a good sail trimmer, and picking the favorite side of the race course gives greater results that tweaking a few turns on the shrouds.

PS, It's also important to have the top of your mast in the center of the boat.

Jim Stansbury

[Todd Aven]

John,

The mast step on the 92 is adjustable. Here are links to a couple of
photos of mine before and after cleaning it up before Spring launch this
year.

http://www.thinmansailing.net/gallery/maststep/P4160005.jpg

http://www.thinmansailing.net/gallery/maststep/P4160011.jpg

The range is about 1.5" and mine is positioned about 1/3 back from full
forward, which gives me about 21" of rake with the mast centered in the
partners.

Cheers,
Todd Aven
J/92 #14 Thin Man

[Imagine... Hull #45]

Nice pix Todd but no one should assume their mast step was placed in
the exact same position as the next guy's. The previous owner of our
J/92 (#45) had an impossible time tuning the rig and was convinced the
step had not been accurately placed in the boat. He told us that he
ignored J/Boats advise not to move it. After he moved it he had no
problem tuning it and the boat was faster.

Rod Carr
J/92 Imagine... (#45)

[jwhj92s]

James, after reading your first sentence, it makes perfect sense. I
was thinking you tied the halyard to the mast at the draft stripes in
the mainsail. Duh!!! The mast crane and tack are not flush with the
sailtrack and, yes, lashing the halyard at the black bands will give
an accurate figure on prebend. I also agree, that the most speed can
be gained from a fast bottom and a good sail trimmer. The shrouds on
the S are swept back more than the traditional 95, therefore, I think
tight uppers and loose mids and lowers will bend the mast even more.
My sailmaker says, not much prebend at all, almost straight; we'll
experiment till we get it right.

John

On Nov 18, 8:58 pm, "James R. Stansbury" <jim.stansb...@strickland-

> > - Show quoted text -- Hide quoted text -

[jwhj92s]

Yes, I see how your step can be moved forward and aft. I am going to
double check mine, but when we stepped the mast, I recalled only one
position.

John

> > Is the maststep in a 92 adjustable?  The S has a fixed postition.- Hide quoted text -

[furkolkjaaf]

On 18 Nov, 23:53, jwhj92s <j...@diversifiedfoods.com> wrote:
> Keep us posted.  We sailed the last race of our fall series, this past
> Sunday.  Next series will be the Sugar Bowl regatta, then the winter
> series.  We get to sail year round here, although it does get pretty
> nasty.  I saw alot of videos of you on the Thin Man site, your boat
> looks very nice.
>
> John

John, I think u are confusing me (Max) with Thin Man. Thin Man has a
great website, for sure !
I understand he has the "classic" (or "old style", or whatever...)
while I have the S.
I think u are right that the S has a fixed mast step, which makes
thinks complicated as far as rake adjustment is concerned.
I was wondering how the Santa Barbara guy managed to move mast step on
the S, doesnt sound as an easy job...

Max

[jwhj92s]

Thin Man said the same thing, but on his site he has a video link to
Youtube which has thumbnails on the bottom of related videos. That is
where I saw alot of videos of your very nice looking S. So, you see,
I did see your boat videos on the Thin Man site. Now that thats
clear. :-)

The boat in CA, had more than just the mast step moved. They moved
the step so far forward and raked the mast so far back, they had to
lengthen the headstay, shorten the backstay and recut the mainsail to
keep the boom out of the cockpit. I'm not willing to make those
changes to my boat, even though that boat won so many races it's
rating was dropped to 84, I'm at 99; and will do my best with what
I've got.

John

[furkolkjaaf]

Oh now I see it...!
I do not like either making such massive changes on mast step setup
etc, but I was wondering whether it makes such a big difference....
I'm quite convinced that this boat is somehow tricky to get optimized
and fully up to speed...
Sometimes I feel so fast some others so slow...but not sure what makes
me do either way...
max

[jwhj92s]

I know exactly what you mean!! I wonder if the traditional 92 is the
same way??

John

> > > Max- Hide quoted text -

[furkolkjaaf]

As for the rake thing (on a J92S):
I've just got a ballpark value from my sailmaker at 55-60 cm (=
distance from mast to main halyard coming down vertical at boom
level).
Anybody having a clue on what you are using out there ?
I'll check my setting this weekend and will let you know...
Max



On 19 Nov, 03:58, "James R. Stansbury" <jim.stansb...@strickland-

inc.com> wrote:
> John,
>
> In measuring mast bend, I wanted to measure bend as seen between the mainsail track and a imaginary straight line between the top and bottom black bands on the mast.  As the main halyard exits the mast at the top, it over 3" away from the sail track.  When the halyard is attached to the gooseneck, it's around 3" away from the sail track.  If left this way, I would have an offset in my measurement.  I wanted a baseline measurement of 0 both at the top and bottom black band.  Therefore, I tied a line around the mast and the halyard to pull the halyard tight to the mast at the top and bottom black bands.  This gives my graph and table a baseline of 0 at the two black bands.
>
> With this done, the gap you see in the middle of the mask between the sail track and the halyard with the backstay slack is your pre-bend.  If you don't see any gap, you don't have pre-bend.  No pre-bend is unusual on a fractional rig.  In my measurement table, in the first column is my pre-bend with backstay at position 1 or 0" of tension.  I have a pre-bend of 1.75" as measured at the upper shroud.  
>
> Mast pre-bend in a fractional rig is created by mast compression caused by tight upper shrouds and relatively loose lower shrouds, which let the middle of the mast move forward as the mast compresses.  If your lower shrouds are too loose you will see mast sag or out of column, the middle of the mast bows to the low side, in heavy air and mast pumping in heavy seas. Both are bad.  
>
> My loos gauge doesn't tell me when my rig is tuned correctly, it tells me when my port and starboard shroud tension is even.  Sighting up the mast along the sail track and seeing a nice straight and even bow in the mast under different wind conditions and  seeing the amount of bow controlled by the backstay tensions tell me when my rig is tuned.  
>
> Boat speed tells me I'm using my sail control lines (including backstay) to create the right sail shape and draft to match the wind and wave conditions.
>

> The amount of weather helm in my tiller tells me I have the right maskrake.  I like a neutral helm.

>
> North built my class sails, and Quantun build my kevlars for PHRF.  Your sailmaker should cut you main's luff curve to match your mast bend.  My sails are so old picture are useless.  My mast step base is adjustable about 1.5".  
>

> Between the adjustable mast step and blocking the mast in different positions at the cabin top, and adjusting forestay length, all combine to adjust mastrake.  I tried to measure mastrakeusing the main halyard as a plumb-bob with the boom level to the horizon (use a level). I tried to measure the distance between the mast and the end of the main halyard as it came to rest on the boom.  The boat moves around in the slip too much and the measurement was very subjective due to weight distribution of the equipment in the boat (you need to empty the boat).

>
> I found that a fast bottom, a good hand on the tiller, a good sail trimmer, and picking the favorite side of the race course gives greater results that tweaking a few turns on the shrouds.  
>
> PS, It's also important to have the top of your mast in the center of the boat.  
>
> Jim Stansbury
>
> -----Original Message-----
> From: j92o...@googlegroups.com [mailto:j92o...@googlegroups.com] On Behalf Of jwhj92s
> Sent: Tuesday, November 18, 2008 12:33 PM
> To: J/92 Owners
> Subject: [j92owners] Re: J92s, Hull#30
>
> Great info James.  When you say you tied a line around the mast and
> halyard at each black band, what do you mean?
> I can see the main halyard running from top to bottom and the space
> between being the prebend measurement, this would change at each
> backstay setting.  But, if the halyard is tied to the mast, how do you
> measure the distance?  So, who built your sails, and how do they
> work?  Any pictures?  Sounds like a good plan, the more data you can
> give your sailmaker, increases your chances of getting a good sail.
> Is the maststep in a 92 adjustable?  The S has a fixed postition.
> Will these measurements all change if you change your rig tensions?
>
> John
>
> On Nov 17, 10:25 pm, "James R. Stansbury" <jim.stansb...@strickland-
> inc.com> wrote:
> > John and all the lucky J92 owners,
>
> > I have attached my analysis I did of my boat's mast bend when I was buying new sails for my J92.  I spend months trying to tune the rig and came to the following conclusions:
>
> > 1)      Tune mast pre-bend and max-bend to the mainsail cut.  My sailmaker found my measurements of my mast bend with various backstay adjustment most helpful.  My sailmaker was also interested in the keel profile, which he already had access to.

> > 2)      Tune mastraketo the feel of the helm.  I raked my mast until I felt just a little weather helm.  I didrakethe mast too far back to get a feel of how bad the helm could get, then raked it forward until the helm was just right. My mast step base is all the way forward.  Mastrakemoves the center of effort of the main and jib in relationship to the center of effort (or lift) of the keel.  This effect the feel of the helm.  I did not need to cut my forestay to find my sweet spot for the helm.  

> > 3)       The lower shroud tension controls how much your mast will bend and what the arch will look like when applying backstay.  Tight lowers will not let the center of the mast bend forward when backstay is applied.  I look for lots of nice even bow in the mast when I apply backstay so I can control or flatten the mainsail.
> > 4)      Forestay sag is something I could never figure out how to measure.  Upper shroud tension seems to control forestay sag when the backstay is slack but adds pre-bend.  Increasing backstay does decrease forestay sag but flattens the main with mast bend.  Forestay sag is the Achilles' heel of a fractional rig.  This is my problem area that I actually tuned the rig to eliminate.    
> > 5)      I play the backstay very aggressively when the wind is puffy.  It really changes the shape of the mainsail more effectively in those conditions that the mainsheet.  I see the backstay as a mainsail control line, it just happened to attach to the top of the mast.
> > 6)      I made my backstay a 32:1 system with marked increments of adjustments so I can return to an known adjustment.  I can pull my backstay over 4" with little effort, but it takes lot of backstay line.
>
> > To take my mast bend measurement, I sent a guy up the mast on the spinnaker halyard with a measuring tape. I found the lightest person for the job so not to affect the mast bend.  I ran the mail halyard down to the gooseneck and tied a line around the mast and halyard at each black band to pull the halyard against the mast at the bands.  With the guy sitting in the bosun's chair at each measurement position at the mast, I adjusted the backstay to each of the nine backstay positions and a measurement was make between the mast track and halyard.
>
> > Also, I hope no one is using wire halyards or backstay.  They were standard on my boat.  I did a weight reduction analysis when I replaced mine but lost the numbers.  The weight reduction was dramatic.  
>
> > Jim Stansbury J92 #27 UBIQUITOUS
> > 240-401-7944
>
> > -----Original Message-----
> > From: j92o...@googlegroups.com [mailto:j92o...@googlegroups.com] On Behalf Of furkolkjaaf
> > Sent: Monday, November 17, 2008 3:52 PM
> > To: J/92 Owners
> > Subject: [j92owners] Re: J92s, Hull#30
>
> > On 12 Nov, 16:48, jwhj92s <j...@diversifiedfoods.com> wrote:
> > > I spoke to Ken at The Chandlery yesterday.  He said the boat liked

> > > alot of mastrake, so much so, they lengthened the headstay, shortened

> > > the backstay, moved the step forward and recut the main to keep the
> > > boom out of the cockpit.  I was told the S liked a straight mast, no
> > > prebend by more than one respected sailor.  Ken's boat won enough
> > > races to be rated 84, maybe he was onto something, most of the J boats
> > > I sailed in the past liked prebend.  I will probably readjust my rig
> > > to setup as much prebend as the stock rigging will allow and see if I
> > > gain any advantages.  Any thoughts?
>
> > > John
>
> > John,
>
> > this guy, Ken, sounds like he's a guru of the 92s...

> > How muchrakeare we talking about ? There must be some precise data

[furkolkjaaf]

I promised I woud post my current mast rake so here we are.
I took the measurement today and the boat was on the cradle, not in
the water.
So it must not be a super accurate measurement, although I've
corrected the result considering the slight waterline inclination that
I've measured.
The "corrected" rake is around 70 cm (27.6 inches, distance from mast
back face to halyard, coming down perfectly vertical from mast top).
This translates into 3.4 degrees inclination, which is more than what
I've guessed before.
Bottom line, it seems not far away from recommended ballpark,
generally speaking.
I've heard that 2-3 deg is normal (but not necessarily specific to the
J/92S).
It would be interesting to know what do you have out there...

Max

[jwhj92s]

Thanks for the info Max, I will measure our rake, using your
discipline. When you took these measurements, there was no backstay
on, right?

John

> > > > John- Hide quoted text -

[furkolkjaaf]

John :
exactly, no backstay.
Max

[Todd Aven]

To measure rake, you really should remove all loads from the mast.

- all halyards eased
- shrouds eased to hand tight
- backstay slack

The moment you put cap shroud tension on, you move the tip aft (and
down). This directly affects rake measurement.

On Dec 22, 2008, at 4:59 PM, furkolkjaaf <eliomas...@gmail.com>
wrote:

[jwhj92s]

I will measure my rake, the same as Max, therefore we can compare
apples to apples.

To get the natural, designer intended rake, I will use your method.
The S has swept back spreaders, therefore shroud tension, especially
upper, will greatly effect mast rake.

The way I see it, Max and I have the same boat, but not the same
sails. Different rig settings will create different rake numbers,
which may vary widely between our boats, but still be correct for our
individually cut sails. I am still new to this boat and want as much
info from other owners as I can get.

Looking forward to sailing our Mardi Gras Regatta, in early March and
hoping to be more competetive, keep the advice coming; I can use it
ALL!!

John

On Dec 22, 9:51 pm, Todd Aven <t...@avenshaven.net> wrote:
> To measure rake, you really should remove all loads from the mast.
>
> - all halyards eased
> - shrouds eased to hand tight
> - backstay slack
>
> The moment you put cap shroud tension on, you move the tip aft (and  
> down). This directly affects rake measurement.
>

> On Dec 22, 2008, at 4:59 PM, furkolkjaaf <eliomassimop...@gmail.com>  

> >>> - Show quoted text -- Hide quoted text -

[Todd Aven]

I understand what you're saying about ensuring valid comparison. At
least make sure your shroud tensions match his.

[furkolkjaaf]

I think this is a good point.

Indeed I made my measurement with backstay slack, halyards released,
but, as for the shrouds, I only had taken away 5 turns from the high
and 2 from the intermediates and lowers from my base setting which was
34/12/20. I wasn't too much concerned about the effect of shroud
tension on the rake, but as Todd pointed out, I was probably wrong.
However, my feeling is that such tension should affect the rake
measurement one inch or so...but maybe I'm wrong again.... :-)

Max

PS I take this opportunity to wish you'all guys a very happy
Christmas, and a healthy 2009 !