Hobie Cat Forums

It is currently Mon Sep 22, 2014 2:42 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 54 posts ]  Go to page 1, 2, 3, 4  Next
Author Message
PostPosted: Mon Apr 09, 2012 1:00 pm 
Offline
Site Rank - Captain

Joined: Sun Apr 17, 2011 6:31 am
Posts: 71
Location: Johannesburg, South Africa
This last weekend I suffered humility by being properly beat even by H14's. I could point but could not match their speeds, they came flying past. I was devastated.

So I sat down to analyse what happened.

My sails are new, my mast is raked for max power, rig tension is not tight tight nor is it loose, rudders are perfect with no adverse helm.

Ultimately I came to the conclusion that it could only be my sail shape, i.e. wrong batten tension with incorrect foil profile and the pocket in the wrong position. The sails were considered flat for the moderate wind conditions.

Cutting a long story short and with commiserations at the club pub, one of my sailing colleagues whom sailed H18 worlds in the 80's, gave me a book entitled THE HOBIE 18 PERFORMANCE MANUAL written by PHIL BERMAN.

WOW..... for those who really want to go faster, I really suggest this book. It has everything how really to set up the H18.

So next weekend I am going to have the H18 on its side going through all permutations.

Cheers and good reading

_________________
Richard Stephens
Image


Top
 Profile  
 
PostPosted: Thu Apr 12, 2012 6:55 am 
Offline
Site Rank - Old Salt

Joined: Thu Sep 24, 2009 5:50 am
Posts: 379
Richard, I know how you feel, the top two H16s in our fleet beat me every time straight up. It has usually been close and there are points of sail/conditions where my H18 appears to have a distinct advantage but I have yet to beat them. I'm sure part of it can be attributed to my 27-year-old blown-out sails. But even more, I think our top two H16 sailors are just better sailors than me and the boats are a lot closer in speed than some people think. If the wind and seas are up I like my H18s chances. In moderate conditions....not so much.

I've been trying to get a hold of the "Hobie 18 Performance Manual" for quite some time now with no luck. Another excellent resource is "Catamaran Racing for the 90s" by Rick White. There are a lot of good tips in this book. Earlier this week I purchased "Catamaran Racing From Start To Finish" by Phil Berman for $6 via Amazon.com. Should be arriving in the mail any day now.

Best of luck with your new sails. They sure do look nice. I assume you're using telltales to help with the trim?


Last edited by BrianCT on Fri Apr 13, 2012 12:08 pm, edited 1 time in total.

Top
 Profile  
 
PostPosted: Thu Apr 12, 2012 8:38 am 
Offline
Site Rank - Old Salt

Joined: Mon May 09, 2005 10:25 am
Posts: 2570
Location: Jersey Shore
I agree that the 16, 17, & 18 all tend to be pretty close in speed. The skill of the sailor(s) has as much or more to do with which boat is faster than the actual boat in many cases. The 16 is at an advantage in some ways because it has such a large class compared to the 18, so it tends to attract higher caliber racers and the tuning of the boat has become very refined. So an experienced 16 racer will almost always beat a less experienced 18 racer - any difference in speed between the boat designs doesn't make up for the advantage of experience.

I have an old copy of the 18 performance manual laying around somewhere, but honestly, I haven't looked at it in years. I think if you rely too heavily on that book, you end up putting too much emphasis on the tuning aspect of sailing and not enough emphasis on the things that really matter, like good starts, boat speed, tactics, getting your head outside of the boat, etc. I actually think Catamaran Racing for the 90's is a better book because it actually discusses tactics and strategy which are much more important to racing success then the things that are discussed in the Performance manual.

I would use the manual as a reference to get yourself set up in the ballpark, but don't take it as the gospel truth. The 18 has a couple adjustments you can make, but really, it's a pretty basic boat and I've found most of the adjustments don't seem to make a whole lot of difference. Make sure your boat is set up balanced, the mast rake is about where it should be, and you have a good working downhaul. Those are probably the most important things in my opinion. Having a fresh set of sails doesn't hurt either.

sm


Top
 Profile  
 
PostPosted: Thu Apr 12, 2012 12:27 pm 
Offline
Site Rank - Old Salt

Joined: Wed May 17, 2006 7:49 am
Posts: 1073
Location: North Carolina
The book is useless once you change sail type, you have a mylar squaretop not a dacron pin top. If your sail is a Whirlwind chances are its not balanced. Mine was too flat in the top half, when I sheeted in to power the lower sail the top would stall. Had to send it back to be reshaped. Also run your rig slightly tight and keep the diamonds fairly tight if not very tight. I try to induce some precurve in the mast but do not suggest you try that.

In moderate winds the 16 and 14 will beat you unless you roll solo. Just the weight difference and drag of the extra hull length is enough to allow them past. Add in a new sail and you don't have a chance.

I really like the spin in just these conditions, everyone trots to "A" mark together but when you make the turn and snap the spin full they eat your rooster tail. If only the H18 had better foils!


Top
 Profile  
 
PostPosted: Thu Apr 12, 2012 1:20 pm 
Offline
Site Rank - Old Salt

Joined: Sun Aug 26, 2007 5:40 am
Posts: 412
Location: Metuchen NJ
racing in one-design is more about what's happening outside the boat. given that you've set-up the boat as best you can, items such as clear starts with speed, staying in clear air, staying between your opponent and the mark (or at least covering your opponent waiting for a mistake), watching the wind shifts, knowing what the tide is doing... all contribute to better results.

an example:
In addition to multihulls, I've spent 11 years crewing on a 36' J109 in one design. On wednesday night club racing, and big regional events like the NOODS and BIRW. The difference is boatspeed between boats can be measured in tenths of a knot, that's it. Until we had an efficient crew system where the helmsman could ignore boat handling and just drive fast, and a tactician who concentrated on what's happening outside the boat with conditions and competitors, we struggled. Once we had the system down, our results improved dramatically.

that said, racing a two man crew, it's a bit tough to handle all those tasks at once. it's best to have a game plan: who handles boatspeed, driving fast, and watching outside the boat. once you have that system down, all you need then is time on the water and experience.

consistency in a crew is paramount. get a good crew and keep that crew.

_________________
Chris
'88 H18SE Arís


Top
 Profile  
 
PostPosted: Thu Apr 12, 2012 7:13 pm 
Offline
Site Rank - Old Salt

Joined: Mon May 09, 2005 10:25 am
Posts: 2570
Location: Jersey Shore
Quote:
In moderate winds the 16 and 14 will beat you unless you roll solo
.

A 14 should basically never beat an 18 around the course, except maybe in a drifter when it tends to be a crap shoot. But an 18 and a 14 of equal skill and both near minimum weight, the 18 will win every time, and especially in moderate breeze. An 18 vs a 16 can be much closer.

If you're on an 18 and being beaten by 14s on a regular basis, you're doing something very wrong.

sm


Top
 Profile  
 
PostPosted: Fri Apr 13, 2012 7:30 am 
Offline
Site Rank - Old Salt

Joined: Wed May 05, 2010 8:28 am
Posts: 702
Location: Clinton Lake, KS
I was gona say... I am a pretty mediocre sailor and an 18 vs a 14 shouldn't be a race at all... Under the right conditions a 14 might be able to match speed (briefly) on a reach... or even running downwind.. Just for a second.. But pointing upwind.. Not a chance. At least that has been my experience vs a great 14 sailor..


I haven't really done any serious racing with an 18 vs a 16, but played around plenty last year.. and the differences are minor enough a good 16 sailor could outrun an average 18 sailor on a course, no doubt.. But all things being remotely close the equal the 18 is so much faster on a course simply because of the ability to point. Enough so that a lesser skilled sailor should be able to keep up with a better 16 sailor short of major tactical errors. At least this was my experience.


My first thought after reading the first post was you are running to much rake. There is no need to rake an 18 back to put the center of power closer to the rudders to make it point... You can use the extra 'power' on the 18... Stick the bows down and drive it hard... but you have the book now so ya probably figured this out already.. :D

And also... I would guess with your sail raking it back would hurt you even more than raking with a stock sail...

but then... ya know my advice is worth what you paid for it. :)


Top
 Profile  
 
PostPosted: Fri Apr 13, 2012 11:53 am 
Offline
Site Rank - Admiral

Joined: Wed Sep 27, 2006 8:32 am
Posts: 257
ncmbm...

i have the sqaretop and its REALLY flat up top.

what's your thought on tapering the top horizontal batten some?
useful or just send the sail back?

if you take off the 'swivel pigtail' atop the jib forestay, you can run the SX forestay and SX jib.. (what i'm doing since I opted to swap for a standard mast and sail setup to sail stock in hobie events... otherwise i just go to the SX forestay and jib, squaretop.. and now I've got a F18HT spin on a I17 endpole.. whoo-hoo)


Top
 Profile  
 
PostPosted: Fri Apr 13, 2012 10:12 pm 
Offline
Site Rank - Captain

Joined: Tue Jun 10, 2003 4:39 am
Posts: 92
Is there interest in a much higher performing set of daggerboards for the H18, not class legal of course? I am looking at building a set for my boat, close in dimensions to the F18 daggerboards, not the new style super high aspect ratio boards but the generation before that (new style boards may require pre-preg carbon and I don't have the tools to handle that). If I go down this route I will likely build molds for the parts needed to modify the trunks. Those parts could be used with any set of boards, if you find a used pair for example.


Top
 Profile  
 
PostPosted: Sat Apr 14, 2012 12:15 am 
Offline
Site Rank - Captain

Joined: Wed Jan 11, 2012 1:00 pm
Posts: 29
samcc99us wrote:
Is there interest in a much higher performing set of daggerboards for the H18, not class legal of course? I am looking at building a set for my boat, close in dimensions to the F18 daggerboards, not the new style super high aspect ratio boards but the generation before that (new style boards may require pre-preg carbon and I don't have the tools to handle that). If I go down this route I will likely build molds for the parts needed to modify the trunks. Those parts could be used with any set of boards, if you find a used pair for example.


High performance foils for the 18 sounds interesting! If not increasing speed and decreasing drag, at least making them easier to use!


Top
 Profile  
 
PostPosted: Sat Apr 14, 2012 12:40 pm 
Offline
Site Rank - Old Salt

Joined: Mon May 09, 2005 10:25 am
Posts: 2570
Location: Jersey Shore
samcc99us wrote:
Is there interest in a much higher performing set of daggerboards for the H18, not class legal of course?


I actually thought about this a little as a mod for one of my boats. I think you would be much better off buying an existing pair of boards and modifying the trunks to fit rather than trying to build your own boards. Used f18 boards do show up from time to time.

The boat should point a little higher and perhaps be slightly more responsive, but I wouldn't expect any radical performance improvements.

sm


Top
 Profile  
 
PostPosted: Sat Apr 14, 2012 3:08 pm 
Offline
Site Rank - Admiral

Joined: Thu Sep 23, 2010 1:58 pm
Posts: 176
Location: SE Michigan / NE Indiana
Have to agree. Unless the challenge of building your own foil is important to you, there's probably not much benefit to create a one-off reinvention of the wheel.

Now what I think would be really cool is to have someone develop limited-run production insert that fits the existing daggerboard well that instantly converts it to Tiger or Wildcat dimensions. Would be important to have design features to limit amount of play. Correct fore-aft positioning will be critical for boat balance.

In the end, though, I'm afraid it would be like putting F1 tires on a Camaro. Definitely cool and better than stock, but nothing that would allow us to hang with the big boys.

_________________
Jeff R
'88 H18 Jolly Mon
'10 F18 Closely Called
Sail Michigan's Great Lakes in 2014
cramsailing.com


Top
 Profile  
 
PostPosted: Mon Apr 16, 2012 6:05 pm 
Offline
Site Rank - Old Salt

Joined: Mon Dec 31, 2007 6:06 pm
Posts: 610
Location: SE PA/ Chesapeak Bay
Richard,

When I converted my P19 (Pinhead) to a P19MX (Squaretop) ... I had the same problem you're having ... since my "MX" sails came from Randy Smythe, I asked him for a mast tuning quide ....

So first things first ... ask the sailmaker to tell you what "LUFF CURVE" the sail is cut for ... this will tell you how much "Pre-Bend" you need to induce into the mast as the mast needs to match the sail !!! You'll need a "LOOS" gauge to set the diamond wire tension properly. My quess is that you'll use MAX spreader rake for that squaretop mainsail. ( My "MX" mainsail needs 1 3/4-2" of pre-bend which means max spreader rake and approximently 500ft-lbs of wire tension on the diamond wires ....)

Second, ask were the "draft" should be ... it will be a percentage of the cord length and will be slightly different for each batten. Did you buy new battons w/ the sail??? I had a sailmaker friend order a new set of battens for my MX Mainsail that came constructed to flex so as to put the "draft" exactly were it was suppose to be ... (between 41-45% depending on the batten for my sail ...) ... if you are using "old" battens, you have some measuring to do and most likely batten tuning/shaping ... (a flat metal file or a electric sander works well ...) There is a very good detailed explination of the process in "Phill's" book .... ( ... and NO you can't have my copy !!!!)

Hopefully this helps gets you headed in a faster direction .....

_________________
HarryMurphey
H-18 mag/ #9458
Fleet 54 Div 11


Top
 Profile  
 
PostPosted: Mon Apr 16, 2012 6:35 pm 
Offline
Site Rank - Old Salt

Joined: Wed May 17, 2006 7:49 am
Posts: 1073
Location: North Carolina
Rob, I don't think the upper batten has any effect on the fullness of the sail. The difference is at the second batten. After the alteration by Chip my second batten is just barely long enough so I guess he added 1 1/2 to 2" of material. If you use tell-tales upper and lower its easy to see the sail stall when you sheet in. Now its consistent top to bottom.

H14 VS H18, I have always encountered the H14 turbo and never ran against a standard H14. The turbo can point and is quick downwind. The guys that have equipped these boats with squaretops and hooters will eat an H18 alive. Thats where my statement came from.

I haved raced my boat in the F18 fleet and can definatively state that the H18 with squaretop, self tacking jib and spin can match the F18s in boat speed upwind and down. I am at best a novice racer, most of the F18 sailors I ran against were seasoned racers that attend most events. My crew is also inexperienced. We could beat any H18 and most other designs racing open class but only successfully beat one F18 on course. I raced F18 boat for boat, not on corrected time. The H18s daggers are the issue as they provide limited lift as compared to the F18 boards. The H18 hull shape and wetted area are almost the same as any F18. Change the boards and the only difference is the curved beams. I would be interested in a removable sleeve system to allow for new daggers.


Top
 Profile  
 
PostPosted: Mon Apr 16, 2012 8:53 pm 
Offline
Site Rank - Captain

Joined: Tue Jun 10, 2003 4:39 am
Posts: 92
If I were to go down the daggerboard project route, the biggest first step will be building the inserts for the well. These would be available as limited production bits.

As far as removable, the upper insert would be relatively straightforward. The issue is the lower insert. It would be difficult to make this removable or accommodating of the stock boards. My stock boards are garbage anyway so I don't really care that much, but there isn't a great way to make the lower insert removable. The upper insert could possibly be designed to handle the loads by itself but there are several variables in that equation, including the specifics of the boards in question.

As far as daggerboard choice, I tend to agree buying a used set would be best. I can build a set for less money but a lot more time. I'm not a big fan of the tiger board design and the wildcat boards are expensive new, few used available. I would try and find a different set of F18 boards from someone upgrading to long boards.

The curved beams and beam location on the H18 are certainly a limiting factor, especially when carrying weight. I had forward and rear beam slapping in very modest conditions on this past Sunday.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 54 posts ]  Go to page 1, 2, 3, 4  Next

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group