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  #1  
Old 10-05-2007
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Pointing Trouble

(As y'all will see, this is a bit about learning to sail, a bit about seamanship and a bit about gear and maintenance, so it landed here.)

Okay, we've had her long enough and gotten enough experience to have learned a couple things and make a couple educated guesses. Let's see if y'all agree.

Facts: Pearson 30. Original sails. Sails are still in good shape, in that they're not blatantly worn or tattered, but I suspect they're a bit blown-out. As I noted in Which Book On Rigging?: The state of our standing rigging is somewhat questionable, as to its tuning/adjustment.

Symptoms: She doesn't point as well as we believe she should be capable. Secondly: She either isn't pointing as high, or we're getting much more leeway, or both, when on a starboard tack as when on a port tack. This is repeatable. You can really see it on a GPS track, where, instead of the track resembling a zig-zag, it resembles "Z"s.

I suspect the general pointing problem a function of the mainsail, in particular, being somewhat (?) blown. We have a new mainsail we can hank on. We've kept the old one on while we learn. Better to beat up the old sail than the new one, right? Secondarily, as we learned racing this last weekend, I think we can point her a bit higher than we've been able to in the past with a bit of fine-tuning of the trim. (Jib trim, fairlead block position and leech line, mainsheet and its traveler, outhaul, vang, etc.)

I suspect the asymmetrical pointing problem is due to the shrouds on the starboard side being looser than those on the port side. When we were bringing her up from her previous home, the PO at one point adjusted the port-side shrouds while we were on a startboard tack. I'm almost certain he did not do the same on the starboard side. And, in fact, when we're close hauled on a port tack, even the top shroud is visibly very slack. Unfortunately, me being the absent-minded type I am, I keep forgetting to eyeball the port shrouds when we're on a starboard tack--to see if they behave similarly.

So, today I'm going to order both Dedekam's Sail and Rig Tuning and Toss' The Complete Rigger's Apprentice, but I'm wondering: 1. What y'all think of my analysis and 2. Are there are any intermediate steps, seat-of-the-pants type rigging adjustments, as it were, I might make now to alleviate the asymmetrical pointing problem?

(As to why I bought neither of the books in that poll yet: Don't ask. The reasons are complex. And perhaps just a bit lame .)

Thanks,
Jim
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Old 10-05-2007
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Assuming your hull and weight distribution is symmetrical (water tank full/empty could matter), then the asymmetry has to be coming from the rig.

The books you're getting will tell you. But use your halyard to measure to each chain plate, see if the distance is the same laterally. And when sailing, sight up the mast to make sure there isn't a hook or a sag.

Beyond that, it's your sails, I think. Adjust the old ones all you want, but likely that new ones will point higher and go faster. A function not just of shape but less stretch and porosity.
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Old 10-05-2007
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SemiJim,

Two quick points:

1) If it were me, I'd bend on the new mainsail. You sound like you're far enough along the learning curve not to worry about abusing it.

2) The leeward shrouds should not be "very slack" as you indicated they are. Fine tuning the rig takes experience and practice, but getting it gross tuned is not that hard. Definitely tighten those sloppy shrouds until they remain mostly taut even when they are on the leeward side (they will certainly loose some of their tension, but they should not be sloppy).

The assymetric pointing ability is most likely caused by incorrect tuning of the shrouds. Overall pointing ability may be due to a lot of different factors, but insufficient mast rake could be one.
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Pointing

First, sails make a huge, and I stress HUGE, difference in pointing ability. If your sails are old, no matter how they may look, they aren't performing that well. You will be amazed at the difference new set of sails will make.
As for the rigging, buy a Loos gauge, from WM or anywhere else, it's worth the investment. They come with a chart with a recommended range for a given shroud size. Follow the directions and make small changes from side to side until everything is where you want it, and this will cure a lot of the unequal port vs. starboard performance. Many boats sail slightly better on one tack than the other, however. There are just a lot of variables involved, and I wouldn't worry about minor differences.
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Jgeissinger's post reminds me that I should have said not to make too many changes all at once. Some of this is trial and error, so make one change at a time, test sail the boat, observe the difference, then make another incremental change. Gradually it should all come into tune.
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Old 10-06-2007
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Thanks for the feedback, everybody. With your comments, and input from elsewhere, I think I have what I needed.

I also talked about it with the PO yesterday. He hadn't realized he'd had a brain-fart and had tied the turnbuckles incorrectly. ("What in the hell was I thinking?," or words to that effect, was his response, when I told him what I'd found.) He told me how to get her roughly back in tune. Amongst other things: He told me opposing shrouds are so close to identical, wrt length, that a good start is to match the lengths between the turnbuckle bodies on the starboard side to those on the port side. I'll of course use the main halyard to measure to the main shroud chainplates on each side, and eyeball the mast to see that it's plumb. After that, he said, it's mainly a case of sail her and find out what needs to be done from the way she sails. (Kind of along the lines of what John suggests.)

Somebody on the P30 mailing list also pointed me to a rig tuning guide written by Bill Shaw. I kinda suspect he probably knows what he's talking about . So I'll add that info to the mix.

Haven't been able to convince The Admiral of the need for a Loos gauge. Doesn't help that most people on the P30 mailing list, the PO, and everybody we've talked to at the club, incl. our sponsor, says "You don't need it."

Jim
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Old 10-06-2007
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Jim how does your helm feel when it breezes up? Can you get the boat to balance with sail trim alone? You should be able to balance your boat where it will practicly steer its self. If you can't then your sails are fighting your keel.
your center of effort and your center of resistance are not lined up.
In Dedekams book there is a methode of tensioning stays by elongation of the wire It was too big of a pain for me and I bought a loose gauge insted. Tell moma that if she likes your cheerful disposition that you can afford one.
It will save you a hell of a lot of time.
I think its critical that booth sides be as equal as you can possibly make them or you will continue to fight this problem.
Follow the instructions That Ivar lays out to a tee and in order. I tried to cheat and do it all static at the dock. It doesn't work. the final bit will have to be done under sail in moerate to heavy air close hauled. It took me abought five times through the whole rig. over three months to get Our boat where it is now.
The net results were;
1 no more excesive weather helm Boat will almost self steer
2 cut 10 degees off of our over all tacking angle
3 gained almost a full knot by not having the keel and sails doing battle
4 upped our enjoyment sailing the boat by ten fold. It is way easier to balance and depower now we don't get that over powered feel to the boat untill about 20+knts. She stays on her feet better which makes Joni really happy
5 We did all this with ten year old tiered sails. Then bought a new head sail and it just got even better.
If you get your rig perfect the rest of the sail trim issues will fall into line. and you will see much faster responses in the boat when you start tweeking.
Your track wont look any thing like a Z it will look more like a straight line with fire coming off of it.
Hope this helps
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Jim,

Everyone here is right. We have a 30' US Yachts, and she points like a champ. She gybes and tacks on a dime. Sails like a dream! All rigging and sails are tuned perfectly. However, the only time old girl will not point is at anchor. Due to her hull design, and the fact we have no bowsprit or anchor roller (we bought an anchor roller, and despite careful measuring, it won't fit right), the anchor is off to the side. So she is a squirrelly girl at anchor (but we do use a kellet, just in case!) Once you get the new main up, and everything tuned right in the rigging, you will notice a huge difference in her pointing when sailing. Also, you might want to make sure she is sitting right and add ballast where needed. (We had to add some lead after Wu-Wei got a new engine, as it made a difference.) Good luck and happy sailing! Pearsons are good boats!

Chris
US 30' Wu-Wei
http://www.diysailor.com
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Old 10-07-2007
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Chris, have you ever tried using a bridle on the anchor rode to cure that?
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Quote:
Originally Posted by soul searcher View Post
Jim how does your helm feel when it breezes up? Can you get the boat to balance with sail trim alone? You should be able to balance your boat where it will practicly steer its self.
"Practically?" There's no "practically" to it. On some tacks we can literally let go of the tiller and it stays put. My wife has, more than once, let go the tiller to grab a drink of water simply because her tiller hand was closer to her water bottle

Quote:
Originally Posted by soul searcher View Post
The net results were;
1 no more excesive weather helm Boat will almost self steer
Already there.

Quote:
Originally Posted by soul searcher View Post
2 cut 10 degees off of our over all tacking angle
Yet to be seen. (See below.)

Quote:
Originally Posted by soul searcher View Post
3 gained almost a full knot by not having the keel and sails doing battle
Already there. We're been getting good speed (5-6 kts DDW in 5-6 kts of true wind. Repeatable. A couple of max speeds, so far: 7.5 kts on a beam reach, w/just the main, reefed, in 15 kt winds, gusting to near 20 kts. [Our 1st time out.] 8.2 kts on a close reach in 15 kt [?] winds with the 155 up.)

Quote:
Originally Posted by soul searcher View Post
4 upped our enjoyment sailing the boat by ten fold. It is way easier to balance and depower now we don't get that over powered feel to the boat untill about 20+knts. She stays on her feet better which makes Joni really happy
Yet to be seen. (See below.)

Quote:
Originally Posted by soul searcher View Post
5 We did all this with ten year old tiered sails.
What we've been flying are 31 years old .

Quote:
Originally Posted by soul searcher View Post
Then bought a new head sail and it just got even better.
We bent-on the new main last weekend. Thing looks like it's hardly been used. We brought out the light 155 and we'll be bringing the heavy 155 with us next weekend. (It's Kevlar, apparently. The new main is Dacron. I don't know what the light 155 is. Wifey says it's somewhere between off-white and kinda tan. Mylar? Kevlar?)

The rigging is all straightened out. Had some guests from Canada at the club this weekend. (Apparently they come every year at this time to spend Canadian Thanksgiving Day at our club.) Mentioned to one of them our suspicions about our rigging. "Ask Brian," he replied, "He'll know. Brian's forgotten more about rigging than most people will ever know." Well, Brian did know. And he spent about a half-hour or 45 minutes with us, a pair of wrenches and a screwdriver, getting our rigging tuned. Then gave us a lesson on the back-stay tensioner: When and how much to use .

We're very much looking forward to this-coming weekend, to see how she sails now!

(Now if only those damn weeds will float off...)

Jim
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