PDA

View Full Version : I need help with this sailing business....please!



ACB
07-10-2001, 05:44 PM
Thirty years of sailing big boats has left me ill prepared for little ones....

OK, the story so far....

Last year we turned a 16ft pulling boat into a launch, essentially by adding false keel, floors, engine beds, shaft and a secondhand Yanmar 1GM 10. Oh, and a rudder (surprising how far we got before we remembered that she would need a rudder!) Sucess.

This year we added a mast, a gaff mainsail and a jib. Partial sucess.

As a motor sailer, she does fine. The false keel is substantial enough to reduce leeway to almost nothing....where the fun starts is when we try to go about....she won't look into the wind. By the time she is head to wind she has lost way. She has, of course, a launch type rudder, not a sailing boat rudder.

I think the "batting order" of modifications is flatter jib, in place of present secondhand baggy one, fit drop plate on rudder, add bowsprit; in that order, but what have I forgotten?

Greg H
07-10-2001, 05:58 PM
I suspect you need a leeboard or the equivalent. Something for the boat to pivot around so all your foward momentum isn't lost in leeway. I had an 8' dinghy with a long shallow keel and it wouldn't tack worth a darn, after living with it for a year or so I installed a daggerboard and it made a world of difference.

ACB
07-10-2001, 06:05 PM
Thanks; very interesting point. I noticed that a friend's Drascombe (sorry to mention frozen snot here!) has a pair of very short deep bilge keels as well as a long central false keel. Same idea, presumably.

Greg H
07-10-2001, 06:27 PM
You could try an experiment with a plank fastened to the gun'l with a couple of clamps. Not elegant but.....

Rich VanValkenburg
07-10-2001, 06:36 PM
You mentioned 'pulling boat'. Are you talking Whitehall-type? The Whitehall isn't very friendly when tacking as a sail driven boat. The false keel, if it's stem to transom, just might be why it won't turn with enough way on to tack over. It was designed to help the boat track true when under oars.
You might want to visit these guys-- http://www.tsca.net/puget/

They were having quite a discussion this Spring about getting pulling boats to turn properly under sail.

John B
07-10-2001, 07:33 PM
By modern standards, the pivot point of a board is the obvious solution. Historically and with a full length keel, it might point to the reasons for the lug rig ( with it's centre relative to the mast) and the prevalence for split rigs like the yawl so that you have other options to assist the tack.
What's the sailing helm balance like ?

Phil Young
07-10-2001, 08:08 PM
See all the threads on Lulu. A couple of bilge keels might do the trick, bit of framing inside, metal plates on the outside, no or minimal increase in draft, handy for drying out.

Ed Harrow
07-10-2001, 08:37 PM
Ya gotta station somebody forward with an oar or paddle, at the appropriate moment have them do a "cross-draw stroke". Works great in canoes, if you don't get yanked out, LOL.

Mike Field
07-10-2001, 09:41 PM
Something else that might be worth considering (in addition to wehatever else you might choose) is whether you could set your jib on a bowsprit. This wouldn't be a cure -- you would first have to find some way of getting her head-to-wind with a little headway still -- but it might help ensure that she does indeed then tack. It would give you extra moment, so if the jib's kept sheeted in as you go about, the head gets pushed around and then pays off more certainly.

Of course, with a bowsprit you might be able to set two headsails, and the extra canvas might then give you the little extra speed you need to go about (in which case let the staysail sheet fly when you're head to wind, but keep the jib sheeted in.) Two headsails would be a fair bit of work on a sixteen-footer, though.

Or alternatively, instead of tacking you could just wear all the time.....

[This message has been edited by Mike Field (edited 07-10-2001).]

ACB
07-11-2001, 04:04 AM
Thanks, everyone.

She's much beamier than a Whitehall; 6ft 6ins beam. The shape is more that of a British man-o'war's boat; a good load carrier rather than a fast pulling boat. The false keel has considerable drag; draft aft is about 1ft 10ins. The helm balance under sail is as it should be; mild weather helm.

The rig is standing gaff; mast is about 1/3 of w/l aft of the bow. She just seems to take too long to turn, and stalls before she gets really head to wind.

rickprose
07-11-2001, 06:15 AM
ACB, my guess is the problem is the false keel itself - what you've done by adding it is to increase directional stability to the point that the boat won't generate enough speed to make the turn. directional stability is great in a rowboat, lousy in a sailboat, if taken to an extreme. i think you'll find that if you do away with the false keel altogether, and return her to her original underwater shape, she'll turn just fine and you won't be making as much leeway as you might imagine. i have a bit of experience sailing bahamian dinghies, and they have nothing sticking down underwater except a scan 4-6 inches of keel, and they don't make as much leeway as you'd think. they also come through the wind incredibly quickly.
if you look at a lot of designs for older full keel boats, you'll notice that there's really not a lot of deadwood sticking down under there, for the exact reason that you've so latterly discovered - a little bit of leeway just means you have to sail longer to get where you're going; a boat that won't come about could ruin your day.

ACB
07-11-2001, 06:20 AM
Thanks Rick. I feel that you are probably right, but the false keel was added as a skeg for the propeller and rudder in her primary, "launch" mode! As noted it has quite a bit of drag. I will try to increase the rudder area, by adding a drop plate, and see if I can get round the problem that way!

Tom Dugan
07-11-2001, 08:48 AM
How about removing the false keel from the midpoint forward? A suggestion offered sort of timidly - I'm rather more with the centerboard/leeboard crowd.

G'Luck!

-T

John R Smith
07-11-2001, 09:32 AM
ACB

I hesitate to enter the fray here, especially as you are a sailor of much greater experience. However, we are the owners of a rotund sloop of a certain age, who has always exhibited an extreme reluctance to tack. In fact we spent most of last season trying to modify her wilful behaviour, and in the light of our struggles I can offer the following -

* Lulu also has a long keel, shallow draught, and a small rudder. She tends to do exactly the same - stall before she even gets head to wind, so you can't even get to the point of backing the headsail.

* We improved things a bit by the following tactics -

* Before tacking, sail a point or two more off the wind to build up speed.

* Keep the headsail sheeted tight and drawing well to avoid it bagging and pulling the boat to leeward.

* Don't pussyfoot around with the helm - hard down and slam her through the turn.

* In light airs, forget it. I presume this is because the sail area is too small to get sufficient way on the boat.

Having said all that, I don't think we would stand a chance of tacking at all without the centre-plate. For success, I think you need two things, a deeper rudder and a centre-board or plate. Just my humble opinion, ACB http://media5.hypernet.com/~dick/ubb/smile.gif

John

Mike Field
07-11-2001, 10:10 AM
And here's a belated thought. What if you were to swap the propellor for one with fewer or thinner blades? Retaining the diameter and pitch means the prop will have the same power, but will cause less drag. (You might be able to get a folding or feathering one, too.)

I understand the downside is an increased propensity to cavitate, but from the sound of Piglet this isn't going to be a problem here.

Having said that, I'm by no means an expert on props, and it would be nice to hear the views of one who is.

ACB
07-11-2001, 02:46 PM
John, you have cheered me up no end. At present we have a very, very baggy jib. Its only redeeming virtue is that it cost nothing, but, being an old ships lifeboat jib, it is to real sailmaking what a Trabant is to a Mercedes. And, being used to Mirelle's ladylike habits, where a gentle finger's pressure on the tiller sends her swooping up into the wind, shooting six lengths as we bring the headsails over, (she has missed stays once in the past 17 years, and that was because I had her reefed down too far for the conditions!) I have been far too genteel with Piglet; from now on the tiller will be jammed firmly down, and a more suitable jib will be scrounged or otherwise obtained.....

ACB
07-12-2001, 04:20 PM
Sucess! She tacks. Solution - flatten the jib, get the mainsail setting properly (re-rove peak hakyard), tweak the vang a la Thames Barge to get her looking higher, bang the tiller down, back the jib and we're off!

Thanks to John Smith and to Moray McPhail of Classic Marine, who have also proffered a rudder drop plate, to be fitted during the next dry docking, to make assurance doubly sure...

And she gybes nicely, too! She does need a respectable breeze to get her going, but once she's got it, she goes. What a lovely little boat! By the way, standing gaffs, vangs, brails and boomless mainsails are rather fun!

John R Smith
07-13-2001, 02:44 AM
Great! Didn't realise you had a boomless main as well. I think getting the headsail to draw well is probably the key issue here - you need the forward thrust from this to pull you through the turn. And of course big boats, like your Mirelle, are so much heavier they will keep way on through the tack, even into a rough chop. A little, light boat loses way so quick that the whole business needs more thought, I reckon.

John

Thad
07-13-2001, 05:33 AM
I suggest adding a mizzen right in the stern with a boomkin off the rail for the sheet. You can pull the mizzen to windward as you tack and it will throw the stern around beautifully. Look at pictures of 19th Cent harbor scenes and all those yawl boats and lighters carried mizzens. It doesn't need to be big.

John B
07-14-2001, 05:51 AM
ARRRR.

OK that worked. posting from someone elses computer.
...... I need help.

[This message has been edited by John B (edited 07-14-2001).]

Mike Field
07-14-2001, 07:21 AM
Eh? Wozzat, John?

John B
07-15-2001, 04:10 PM
Well , I was at this dinner at our neighbours place you see. I just sort of noticed this computer sitting there and I just thought that I would see if I could... you know,.. log on.

So I did. A bit of speed reading. And I like the yawl idea.

Thad
07-15-2001, 06:03 PM
I still like it myself. Glad someone else does.

Greg H
07-15-2001, 06:20 PM
John B., do you find youself stopping into cyber cafe's on the way home from work?

ACB
07-15-2001, 07:06 PM
Talking of mizzens, that brailing standing gaff mainsail on the 16ft 'Piglet' is the ex spare mizzen of the 42ft barge yacht 'Growler'!

Thames barges have mizzens for just that purpose, indeed, they used to be sheeted direct to the rudder blade! On the principle that "little fleas have lesser fleas and so ad infinitum", I do have a spare mainsail for 'Minn', Mirelle's 9ft dinghy, which would make a mizzen for Piglet!

John B
07-15-2001, 07:43 PM
How very appropriate. A yawl it is then.
Ferpect.

Greg.... You mean there are other places you can log on???? Oh bliss.

Hughman
02-12-2004, 08:18 PM
ACB?

Piglet? still at the trough? or can we look forward to chops?

:D

Andrew Craig-Bennett
02-13-2004, 02:27 AM
Piglet us underneath a truck tarpaulin and will be until April, as Mirelle has first call on the scrape, sand and paint squad (me!)

And now for a confession - she needs a new mast, as I broke the old one last summer!