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windship 09-04-2002 08:01 AM

What is the difference between a coastal crusier and a bay b
 
Would anybody care to start?

Dennis

JeffH 09-05-2002 04:15 AM

What is the difference between a coastal crusier and a bay b
 
I am not exactly sure what you are asking because the question was truncated. When I think of a coastal cruiser, there are a number attributes that I look for:

-Accommodations:
Good wide berths, at with enough seaberths for at least half of the crew. Good storage to accommodate the larger crowds that is more likely to cruise on a short trip. I am looking for a well-equipped galley that has adequate space to prepare meals for a larger crew or a raft-up. Refrigeration is less important.

-Cockpit:
A comfortable cockpit for lounging is important. It should be larger than an offshore boat to accommodate a larger number of people which is OK since pooping is less likely to occur doing coastal work.

-Deck hardware:
While gear for offshore boats need to be simple and very robust, coastal cruisers need to be able to quickly adapt to changing conditions. Greater purchase, lower friction hardware, easy to reach cockpit-lead control lines, all make for quicker and easier adjustments to the changes in wind speed and angle that occur with greater frequency. There is a big difference in the gear needed when ''we''ll tack tomorrow or the next day vs. auto-tacking or short tacking up a creek.

Keel and Rudder types:
I would say unequivocally that a fin keel is the right way to go here, The greater speed, lesser leeway, greater maneuverability and windward performance of a fin keel with spade rudder (either skeg or post hung) are invaluable for coastal work. In shallower venues a daggerboard with a bulb or a keel/centerboard is the way to go

-Ground tackle:
Good ground tackle and rode-handling gear is important but all-chain rodes and massive hurricane proof anchors are not.

-Sailplan:
At least on the US East Coast, (where I sail and so am most familiar with) light air performance and the ability to change gears is important. It means more sailing time vs. motoring time and the ability to adjust to the ''if you don''t like the weather, wait a minute'' which is typical of East Coast sailing. If you are going to gunkhole under sail, maneuverability is important. Windward and off wind performance is also important.

With all of that in mind I would suggest that a fractional sloop rig with a generous standing sail plan, non- overlapping jibs, and an easy to use backstay adjuster is ideal. This combination is easy to tack and trim and change gears on. I would want two-line slab reefing for quick, on the fly, reefing. I would want and easy to deploy spinnaker as well.

-Speed:
I think that speed is especially important to coastal cruising. To me speed relates to range and range relates to more diverse opportunities. To explain, with speed comes a greater range that is comfortable to sail in a given day. In the sailing venues that I have typically sailed in being able to sail farther in a day means a lot more places that can be reached under sail without flogging the crew or running the engine.

-Ventilation:
Good ventilation is very critical. Operable ports, hatches, dorades are very important. While offshore small openings are structurally a good idea, for coastal work this is less of an issue.

-Visibility and a comfortable helm station:
You are more likely to be hand-steering in the more frequently changing conditions found in coastal cruising and are more likely to have greater traffic to deal with as well.

These are my first thoughts on this topic.

Regards
Jeff

windship 09-05-2002 08:58 AM

What is the difference between a coastal crusier and a bay b
 
Hello Jeff,
I can say that I pretty agree with most of your post.
I don''t agree with keel choise at all.
While it is true that a fin and balanced blade sail best to weather,I think the real question is, how much leeway is acceptable?
This question comes into play when you consider the increased possiblity of groundings and collisions below the waterline.The chances of this are increased in coastal cruising being you are in unfamilier waters, right?Espesially since most fins with external ballast are not designed strong enough to withstand a bad grounding or colision.
I would definatly not choose a daggerboard/bulb set-up for obvious reasons.
My choice is a heavily laid-up hull, internal ballasted modified fin or keel with full skeg rudder or full skeg with aprature for the prop such as the Southern cross underbody.
I also would prefer an anchor platform for quick and easy deployment.
I am re-launching my boat Friday and I have to finnish getting her ready so...thanks for your reply Jeff.
anybody else?

Dennis

JeffH 09-05-2002 04:58 PM

What is the difference between a coastal crusier and a bay b
 
Hi Dennis,

I think this is an interesting topic that you and I have rehashed a number of times but for those tuning late.......I think that there is much that we agree on. Even within those areas that you felt we had some disagreement on, I think we have basic agreements. For example, I think that we agree on the idea of a fin keel and a spade rudder (which as you may notice in my post I suggested that the rudder could be either skeg or post hung). You prefer a skeg hung and I prefer a post hung. The reality is that both can be constructed to be able to withstand equal loadings and that in most cases they are not constructed as substantially as they should be.

Similarly, I think that I agree that it is true that many boats with bolt-on keels are not designed strong enough to take to ground hard at speed without significant damage. But I do think that most quality built bolt on keel cruisers are engineered properly and that it is more common to find a bolt on keel better engineered to survive a hard grounding and to have a long life than you find encapsulated keels.

I think we are in agreement that a coastal cruiser needs to be sturdy to withstand the kinds of abuses that it might incur, although perhaps not as study as a boat that is meant to spend it''s life offshore, where the constant motion really can really lead to a lot of fatique related issues. Where we disagree is in how that strength is achieved. I prefer boats that are properly engineered rather than boats that have a lot of material placed without precision. Both can achieve an equally high level of strength but careful engineering and handling of materials achieves its strength with lower stresses and better performance.

I also agree with the idea of an easy to proper anchoring system but I don''t see what an anchoring platform has to do with that as long as there is a sturdy anchor roller that extends far enough from the hull that the risk of damage to the hull is minimized.

I am not sure what you think are the obvious reasons that you would not choose a daggerboard with a bulb, but to me this an excellent alternative if one were building a custom boat. Properly engineered a daggerboard scabboard distributes the loads to a very large area of the hull offering the potential for a connection that is actually stronger than either an encapsulated or bolted on fin keel and which allows deeper draft for offshore passages and which allows shallow draft for sailing in skinner venues. The nice thing about the bulb is that it permits a very low vertical center of gravity which is helpful in producing a comfortable motion, good stability without using form stability, and good ultimate stability.

I hope your launching went well.

Regards
Jeff

tsenator 09-05-2002 08:26 PM

What is the difference between a coastal crusier and a bay b
 
Jeff et.al.

Love the discussion, but I have a few questions I''d like to ask. You said that a "Properly engineered a daggerboard scabboard distributes the loads to a very large area of the hull offering the potential for a connection that is actually stronger than either an encapsulated or bolted on fin keel ".

I agree and totally understand the arguments for a fin or daggerboard scabboard (performance, less wetted surface area), but I can''t really see your argument that it will be stronger than an encapsulated keel. The way I see it if you have a boat that ran aground on a sand bar or on a reef ( a reality and concern with coastal cruising) that the boat with an encapsulated modified full keel will withstand the torsional and leverage arm forces much better than a fin or daggerboard.


JeffH 09-06-2002 04:03 AM

What is the difference between a coastal crusier and a bay b
 
Good question. You have to look at how an encapsulated keel is constructed. In most cases that I have encountered, the laminate for the hull of the boat is continued downward into the keel area so that there is a sharp turn in the laminate at the point that the hull turns down into the keel. In properly engineered bolt on keel there are heavy tranverse frames at the top of the keel that distribute the loads outward into the hull. In the case of the daggerboard scabboard the scabboard is glassed in at the hull and deck creating a large lever arm. But in the case of most encapsulated keels there is very little framing involved. The loads are being applied perpendicular to the comparatively thin skin of the hull. This results in more flexure and that flexure can result in fatigue over time. It can also pry the sides of the encapsulation and waterproof membrane at the top of the keel loose from the ballast keel.

In an encapsulated keel, the watertight membrane is below the ballast keel where it can be exposed to the full impact and abrassion of rock or coral. Generally above the ballast keel there is a thin membrane that simply keeps bilge water out of the ballast cavity. In a bolt-on keel the hull passes across the top of the keel so that the watertight membrane is not exposed to the actual impact with coral or rock.

The laminated keel itself is difficult to layup well as the yard crew is forced to work in the narrow confines of the keel cavity. In my experience trying to repair encapsulated keels the glass work at the bottom of the keel is often quite thick but very poorly laminated. Big voids, unwetted out cloth and unreinforced lenses or resin are quite common. Placing the ballast so that it is properly adhered to the sides of the ecapsulation is quite trickly. Last year when this was discussed I believe that we found by walking through boat yards and tapping on keels that somewhere between 25% and something less than 50% of encapsulated keels had voids between the encapsulation and the ballast keels.

What this means in a hard grounding is that the skin is more easily pierced in an encapsulated keel, there is less to resist the ballast keel from being forced upward and once forced upward the boat has damage that is next to imposible to to repair. I have cited as an example my family''s Pearson Vanguard that clipped a rock at 4 knots which was enough to crush the encapsulation and drive the ballast up through the water proof membrane and dislodge the tank above.

With a Daggerboard a well engineered scabboard has a hard rubber crush block that absorbs much of the force of an impact rather than distributing the impact loads into the hull. Again the water tight membrane is not exposed on impact.

Jeff

windship 09-06-2002 11:12 AM

What is the difference between a coastal crusier and a bay b
 
Hi Jeff,
I love these debates on underbodys.To me it''s determines what the boat should be used for.
Anyway...
First of all,I dont think there are many ex. ballasted(lets call them EB and IB ok?) boats that will survive a four or better kt. colision.
Do you consider Sabre a well designed yacht?I would hope you do,because they are.Now my friend has a Sabre thirty-eight with
,of coarse, an EB keel
When he bought the boat in ninety seven I had to repair the stringers in the foward part of the bildge(BTW EB boats don''t have much bildge either).Three out of five of them were broken and the dent in the leading edge of the keel looked like three or four kts.The same friend was lust telling about a C and C forty three or four that had hit something and you could put your hand through the hole/crack at leading edge fillet.That boat came extremely close to being lost.I''ve never seen or heard of this happening with a IB keel.The keel is integral.The shock is more evenly dispersed.
Last June when I hauled out because I was going over the road tracter trailer,the wind was N/E @ fifteen to twenty.I had to load on to the trailer heading west with that wind on my stbd qtr. Down wind there is about thirty more feet of room,so, don''t screw up! The driver did not have the drop down through the trailer holes,he had a straight beam.Well, I hit that beam doing four knots. It stopped my boat dead!After she was on blocks and stands I rushed to survey the dammage.Nothing! Not even a crack in the gelcoat.No shifting of the ballest,no voids(in my boat anyway)
and no broken membrane.So much for the leading edge being thin.Also you make it sound as if IB boats have some kind of inadequacy in design around the keel area,in my years of fiberglass repair I find this not to be true.Anyway, I''ve never seen it.Nor have I seen shifting ballast.And not all of the IB boats have their ballest that low in the bildge. My Endeavour thirty-two draws four ft two inches and benith my two ten inch deep by two ft by two and one half ft floor compartments rests the sealing membrane to the ballast... very easily excessable!I think that if the membrane were to break, the only boats where it would be difficult to repair would be very deep draft IB boats.Anyway that membrane isn''t the only thing that holds the ballast in place.What about the back of the keel?And breaking that membrane won''t cause you to loose your boat.
While it is true that we did find some relitively small voids in some IB keels, this repair is simple.
About the daggerboards?You''ll never convince me of that.I''d have to be on the boat and see the whole thing with my own eyes and do the survey myself.
Well Jeff, as you know I just re-launched this morning(all went well thanks)and now I have a date with an island called Weepeckett.
Looking forward to a response,

Dennis

manateee_gene 09-06-2002 05:02 PM

What is the difference between a coastal crusier and a bay b
 
Jeff: you have seen a picture of TPIII''s keeel and daggerboard. On a race around Catalina way back when we had the Dagger board down all the way. Hit a rock which we went over after the dagger board bore the boats entire weight and impact. We hauled as soon as we got back to Long Beach Marina. We drove the board aft 8" in the keel. Had to cut a section out to remove the board. Repaired the cut out section, put the board back in and 30 years later its still going strong. Bye the way the keel has 3200# of lead inside. The box mwmber was built as part of the hull shape the lead was then glassed in a water tank,125gal built on top of it. No Problmo!!
Gene

halyardz 09-07-2002 03:52 AM

What is the difference between a coastal crusier and a bay b
 
I thought Weepeckett was how Mainers referred to a small Island Packet. :-]

NautTwilight 09-08-2002 02:45 PM

What is the difference between a coastal crusier and a bay b
 
All this anecdotal "proof" proves absolutely nothing.
Nobody here has seen enough to eliminate the skewing of results caused by uncontrolled factors.
Only an extensive statistical analysis, or full-scale, carefully controlled tests will conclusively prove which underbody type is inherently safer, and then only for the exact configuration actually tested. Is anyone aware of any of the naval architecture institutes conducting any? I didn''t think so. They''re probably too busy to bother with sailboats. And it''s too expensive for recreational boatbuilders, In any case, The ocean is irrestible enough a force and the earth is immovable enough an object that any hull can be breached like an eggshell and any bolt can be broken like a matchstick. If you want the best hull for a grounding, it won''t be wood or fiberglass.


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