Sailing on a dead run....

Started by Tony, 05 Sep 2016, 11:26

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Tony

Sailing down wind in anything of a swell always caries the risk of an unintentional gybe. The usual answer is to rig a preventer stay.
Here's one example you CAN'T fit on a BayRaider Expedition!
Tony:   CBL#1 "Four Sisters"
www.sailing-in-circles.blogspot.com
http://compare-a-sail.blogspot.com/

Michael Rogers

Presumably, Tony, 'Show a leg' (originally a nautical expression, as any fule no) has a slightly different emphasis for your crew.
Is one allowed, these dreadful days, to express some gallant appreciation without falling foul of the thought police?
The answer to your seamanship 'problem' is, of course, junk rig - which is indeed the answer to most seamanship problems, as I may have pointed out occasionally on this forum.

Peter Taylor

I like the central arrangement for dangling bottles of wine beneath the boat to keep them cool!
Peter Taylor
BayCruiser 20 "Seatern" (009)
http://www.seatern.uk

Tony

Michael:  My wife wont sail in cold water. Her idea of foul weather gear is to replace her bikini top.   Large numbers of perfectly good sailing photos have to be rejected for publication because they would never pass the censor. (Showing a leg is the least of my worries!)  Serves me right for marrying a Trophy Wife .......- and if she ever reads THAT I'm dead!

While I agree that a good junk rig is the ultimate cruising sail - even for small boats like ours - I would respectfully point out that a balanced lug is simpler, lighter aloft and doesnt require the skills of an Orb web spider and several hours of Zen meditation to set up! (BR owners who seem to demand more and more complex and expensive sails with mast tracks, slides, Cunninghams etc, etc should look at Britains inshore fishing fleet in the days of sail. Yes, they are mostly Luggers - and if you think luggers are slow, check out a Goat Island Skiff! .....and down wind even my "Four Sisters" has outsailed a BayRaider - until it cheated by hoisting a spinny. )
Peter: The ugly gallows isnt for dangling bottles of Retsina ( they go over the side as per normal). Its for dangling the dagger board. Being a prototype, "Wabi" is a bit rough and ready - but it all works. (Definitely "Wabi-Sabi". A Japanese phrase in common use amongst East Coast boat builders which roughly translates to  " If'n 'er look roit, 'er AM roit!") Production Deben Luggers have a smart-looking pivoted centre plate  which people seem to prefer.  I dont know why. Its just something else to go wrong in my opinion. "Wabi"s plate is profiled wood, lead ballasted, easily removed for maintainence and will NEVER jam with gravel. To quote US engineer Kelly Johnson; "Keep it simple, stupid!" All a small boat really needs are sails, sticks and string.
....and none of that was about "sailing on a dead run". Report me to the Moderator, why don't you.

Photos: Very rough and ready - and it all comes apart
Tony:   CBL#1 "Four Sisters"
www.sailing-in-circles.blogspot.com
http://compare-a-sail.blogspot.com/

Michael Rogers

Not arguing, Tony. The lugsail is completely underrated. Join the club (of nautical intellectual superiority?)

Michael Rogers

Daggerboards and centreboards ARE about 'sailing on a dead run'. I agree, Tony (again!) about preferring a daggerboard, although I must say yours (meaning Wabi's - not in shot as far as I can see) must be  impressively hefty to need gallows like those, and I've no experience of DBs outside prim little dinghies.

The only DISadvantages of a DB over a CB that I can see are the consequences of hitting an underwater object. A CB will presumably at least try to swivel upwards and minimise the shock to the boat's system (never mind the crew's): a DB won't because it can't, and resultant shock and damage could be appreciable in a strong wind.

It hasn't happened to me - yet!

Peter Taylor

I managed to hit Calshot Spit with the centreboard on Thursday causing the downhaul cleat to release and the centreboard to swing back.  An embarrassing admission given my Coastwatch role at Calshot.. but much less embarrassing than what might have happened if Seatern had a daggerboard. 

On the other hand, if Seatern had a daggerboard I guess I would have lifted it much earlier, rather than knowingly try to sneak over the Spit with a centreboard fully down!

Peter
Peter Taylor
BayCruiser 20 "Seatern" (009)
http://www.seatern.uk

Jeremiah

Quote from: Michael Rogers on 09 Sep 2016, 12:38
The only DISadvantages of a DB over a CB that I can see are the consequences of hitting an underwater object. A CB will presumably at least try to swivel upwards and minimise the shock to the boat's system (never mind the crew's): a DB won't because it can't, and resultant shock and damage could be appreciable in a strong wind.

It hasn't happened to me - yet!

Mike, I can tell you from first hand (if chronologically distant) experience. I used to sail (late 1970s, up to 1981) with a chap who had designed and built his own 23' open ketch 'Gypsy', with DB. One day we were off Clacton/Walton on the Naze, tacking inshore in a stiffish breeze and about to go about because of the groynes coming up ahead, 4 or 5 of us on the weather gunwale, when there was an almighty bang, we all shot forward off our various perches (aka Gypsy stopped almost dead), the boat sagged off the wind and a 30"x18" piece of 1" thick board with a jagged end floated up beside the boat.

Fortunately there was a truncated strip of it left attached, and Gypsy had a deepish keel, so we were able to make it back up to the Orwell with rather more leeway than normal, but it was a salutary experience. From that day I have preferred CB to DB (adjustability is another factor). Notwithstanding that, Cadenza is lovely!  :) Jem.

Tony

At Daggers Drawn...!
Centreboard v dagger board

My two boats ("Four Sisters", a Cardigan Bay Lugger, and "Wabi", a Deben Lugger prototype) are both rigged with balanced lug main and sprit mizzen but otherwise are quite different. "Wabi" has a weighted dagger board and a heavily laid up GRP hull while the CBL has twin, pivoting bilge boards and is light-but-strong epoxy ply construction. Both have been sailed in lakes, estuaries and the open sea in winds up to F5/6 and, briefly, in stronger winds if the weather forecast lied. (Any fool can be uncomfortable and I don't particularly enjoy the Maelström !)

Other boats will be different but I can sum up the advantages and disadvantages of dagger and pivoting boards on these two boats as follows:

1. Its obvious at a glance  when a dagger board is "up" but pivoting boards are out of sight.
2. Weed gets trapped when lifting the pivoting boards, preventing them from fully retracting.
3. If mud or gravel jam in the slots, the dagger board is much easier to clear.
4. The dagger board is instantly removable for repainting etc but the pivoting boards can't be examined without major surgery inside the cabin . They can't be dropped while on the trailer, either.
5. When running down wind, lifting the dagger board reduces drag and any "tripping" effect but increases any rolling. Lifting the pivoting boards bit by bit is much more useful. It moves the centre of lateral resistance aft, helping to reduce any tendency to broach when surfing down waves but still has an anti-rolling effect.
6. Reasonable to think that hitting a rock would be a bad idea with either boat but cause less damage to the boat equipped with pivoting boards. Cant comment as I've never done it. (Well, not yet, anyhow!) Running aground in mud or  sand, however, is an activity I am  very well practiced in. Surprisingly, it's the dagger board that performs best. I just yank on the up-haul and I'm clear and can sail over the bar or use the oars to back into deeper water. With the pivoting boards the initial contact lifts the boards into the slot. You must be very quick with the up-hauls and retract them at once. Any backward movement at all eg wave action, digs the board deeper as it tries to drop. The up-hauls won't pull the boards up once that has happened. You are stuck until you can drop the sails and roll the boat from side to side, winning an inch or two of up-haul with each roll – unless, of course, you haven't jammed everything up with mud and gravel !

So... Neither system is perfect. You pays your money and takes your choice!
Tony:   CBL#1 "Four Sisters"
www.sailing-in-circles.blogspot.com
http://compare-a-sail.blogspot.com/

Michael Rogers

Trust you to have a boat with TWO CBs, Tony! I wonder if your experience sailing downwind (rolling etc) partly has to do with 'Four Sisters' being double ended?

I used to have a GRP Heron dinghy, which had a light wooden CB plus an ingenious friction screw arrangement in the side of the CB case, so that the CB would stay down in any desired position and not float up. It worked well, but in terms of grounding I lost any pivoting upwards advantage of the CB, and might just as well have had a DB. The simplicity of a DB in a small boat is very practical, and adjustability (plus 'stay-down-ability') is fine with a shock cord round the after edge of the DB plus a series of notches in that same edge. However I can understand Jem's preference in the light of that interesting experience of a DB in a heftier boat!

Michael

Tony

Quote from: Michael Rogers on 19 Sep 2016, 18:13
I wonder if your experience sailing downwind (rolling etc) partly has to do with 'Four Sisters' being double ended?

Michael
[/quote/

No. Its harmonic motion, I think. Happens with every boat I've sailed down wind in a seaway, if the wavelengths match the boats natural period of roll.
Tony:   CBL#1 "Four Sisters"
www.sailing-in-circles.blogspot.com
http://compare-a-sail.blogspot.com/

Tony

Oops!
Incomplete post.....

You can "cure" it easily. Alter course slightly so you are tacking down wind or, if that isn't desirable, shift some movable ballast (just don't tell my wife I said so) or do anything else that will alter the period of roll. Easy on a dinghy, harder on a heavier cruiser.
Tony:   CBL#1 "Four Sisters"
www.sailing-in-circles.blogspot.com
http://compare-a-sail.blogspot.com/

Anthony Huggett

Borrowing the weekend's learnings from capsizing my other boat, the "death roll" experienced whilst running can be caused by the top of the sail twisting forwards (say 10 o'clock on Starboard run) whilst the boom remains pointed aft (at say 8 o'clock). One way to calm it down is to apply kicker (which we don't have on Emily, but I'm tempted to try one). Another is to have some centreboard down.

My other boat also has a shock-cord preventer stays permanently rigged through a block on the bow. Works well on a single hander but not sure it could work with the jib on a BR. Perhaps they could go low - through the towing eye?