PDA

View Full Version : Not a bad way to spend the day



Green Ginger
12th June 2008, 06:56 PM
I have been having such a good time sailing my boat I would like to take you all for a sail :doh: as that's not possible have a look at this.

YouTube - Phoenix III

If you are building a sail boat I hope this gives you some inspiration there is a

reward after all the work :2tsup:

m2c1Iw
12th June 2008, 10:18 PM
I was trying to come up with something clever to post here that would describe how envious I am .........but I can't :q so I'll just have to say.

BLOODY GREAT VIDEO

and yes it has spurred me on.

BTW what about some pics of your build.

:D
Cheers
Mike

b.o.a.t.
13th June 2008, 02:40 AM
I was trying to come up with something clever to post here that would describe how envious I am
Mike

I'm with Mike. It's been a lousy day here in the Peoples Democratic Republic of South Australia. And a hectic afternoon shift of work.
Your video WAS my lunch break.
Envious doesn't even go close.

Intrigued by the combo of stayless mast & jib. From a real designer too, not just my furtive efforts to make a pigs ear from a silk purse. Don't see that very often. Do you feel you get enough tension in the jib luff?
cheers
AJ

Green Ginger
13th June 2008, 08:39 AM
I was trying to come up with something clever to post here that would describe how envious I am .........but I can't :q so I'll just have to say.

BLOODY GREAT VIDEO

and yes it has spurred me on.

BTW what about some pics of your build.

:D
Cheers
Mike


Mike
I didn't take too many photos during the build but I reckon I can round a few up I'll post them tonight or tomorrow.Number one priority today is to finish replacing the back stairs "you know who" wasn't real keen on the ladder idea.

Paul

Green Ginger
13th June 2008, 08:58 AM
I'm with Mike. It's been a lousy day here in the Peoples Democratic Republic of South Australia. And a hectic afternoon shift of work.
Your video WAS my lunch break.
Envious doesn't even go close.

Intrigued by the combo of stayless mast & jib. From a real designer too, not just my furtive efforts to make a pigs ear from a silk purse. Don't see that very often. Do you feel you get enough tension in the jib luff?
cheers
AJ

AJ and Mike
Firstly glad you both liked the video. AJ to answer your question I'll quote the designer.....................


The spritsail sloop is one of the few sloop rigs which can carry a jib effectively without stays, shrouds or backstays of any type. This is because the sprit places the head of the mainsail in tension, which is in turn translated into tension in the luff of the jib. Therefore, there are no stays on this boat at all – just place the mast into the step and partner, and off you go!


All I can add is that it does work as she points quiet well and you have the added bonus of easy and speedy rigging so you can get out on the water and get a :D happening on your face.
Paul

mandoman
13th June 2008, 11:08 AM
Wow, famtastic. Thanks for that. After much agonising, Phoenix III is the boat I have finally decided to build. Have even persuaded SHMBO that I should build it. So your video was of great interest.

Fair Dink
13th June 2008, 09:13 PM
Great work, GG. I'm sure we would like to see your other videos as well.

By the way, Mandoman its worth checking out the sistership, First Mate under construction on Ross's website. Its not as pretty as Phoenix 111, but a quicker build.

Green Ginger
13th June 2008, 10:48 PM
I was trying to come up with something clever to post here that would describe how envious I am .........but I can't :q so I'll just have to say.

BLOODY GREAT VIDEO

and yes it has spurred me on.

BTW what about some pics of your build.

:D
Cheers
Mike

Well Mike these photos are the best I could round up, at the time I was building I didn't think to keep a more detailed record of the build I was more interested in timber and epoxy than digital cameras but these should give a pretty good idea of how it all went together. Eight months after starting the boat was launched in March 2006.
Paul

Boatmik
14th June 2008, 11:26 AM
AJ and Mike
Firstly glad you both liked the video. AJ to answer your question I'll quote the designer.....................


The spritsail sloop is one of the few sloop rigs which can carry a jib effectively without stays, shrouds or backstays of any type. This is because the sprit places the head of the mainsail in tension, which is in turn translated into tension in the luff of the jib. Therefore, there are no stays on this boat at all – just place the mast into the step and partner, and off you go!


All I can add is that it does work as she points quiet well and you have the added bonus of easy and speedy rigging so you can get out on the water and get a :D happening on your face.
Paul

Howdy Paul,

The most important thing is to get that smile on your face!!!

I am very much not sure of Ross's explanation that the mainsail arrangement is the reason for the boat being able to sail so well to windward without the luff of the jib sagging. I can see plenty of other rigs that can give you the same effect.

Any rig that gives a good amount of leach tension will do the same job - you can see this happen in any three stayed racing dinghy too - you slack the vang and/or drop the mainsail and the jib stay is almost impossible to tension.

If you have a REALLY stiff mast in that situation the sag is somewhat less.

Also much of the bend that slackens the jib luff occurs in the bottom of the unstayed mast - and the triangulation and tension of the sprit (for the Pheonix's quadrilateral sail setup) in most boats is well above that area.

Having a boom makes a big difference too - as it means the loads of the mainsheet are more directly put into leach tension (tension in the back edge of the sail) which will also jack the masthead back.

The bigger the boat, the harder this is to do - there are a number of larger boats that use the same method with a fully battened mainsail and a powerful boom vang. But to get it to work at reasonable weights they have to move to a carbon $$$ mast and lots of complexity. This is a size factor - not because of the type of rig.

I'd put the credit for the system working purely down to Ross's instinct as to how big to make the mast without it becoming too heavy or being wasteful in materials. Marks of a good designer - he didn't give himself quite enough credit for getting that mast just right.

Thanks for a great thread!

Best wishes
Michael Storer

RossL
14th June 2008, 12:06 PM
Dear Mik,

Thanks for the compliment regarding the mast design :), but I didn't do anything special other than to use my normal rule-of-thumb (copied from Howard Chapelle, Phil Bolger, Norman Skene, William Atkin, Fenwick Williams, Iain Oughtred, and others :wink:). I then increased the diameters by a certain percentage to account for less-than-perfect materials and/or workmanship in amateur construction, and to allow for the use of a hollow mast. The extremely short mast which is allowed for in the case of a spritsail meant that any extra weight aloft was not a major concern.

The exact same mast (and stepping location) is used for the balanced lug option detailed in the plans.

I agree that the leech tension in a conventional rig supplies luff tension to the jib, but it doesn't operate in such an efficient manner as is the case with the sprit-sloop due to the angles involved. Also, leech tension in a conventional rig increases compression loads on the mast (a bad thing :~) whereas head tension in the spritsail decreases mast compression - a good thing :).

Paul has done a great job of building his Phoenix III and has sailed her far and wide :2tsup:. There is a link to another good clip of Paul's boat under sail on the home page of my website. It is taken for outside the boat, so you can see what she looks like under sail. www.baysidewoodenboats.com.au (http://www.baysidewoodenboats.com.au)

Ross Lillistone

Boatmik
14th June 2008, 01:17 PM
I hoped you would be along Ross!

The shortness of the mast is another important factor in keeping the jib luff as tight as possible and that is where the quadrilateral sprit rig IS unusual.

The only rig with a potentially shorter mast for the same area and height of rig is the lateen or some close derivative. And they ARE tricky to make work with jibs!

MIK

Daddles
14th June 2008, 01:22 PM
Cor, with all these designers on the forum it's in grave danger of getting some credibility. Good thing there are enough iggorant amateurs like me on here to keep the balance :doh:

Richard

Boatmik
14th June 2008, 02:09 PM
And you do such a good job!!!!

mandoman
14th June 2008, 02:32 PM
Yes Fair Dink, I have been following the developments on Ross' web site so know about First Mate. However, lapstrake is what I want, and it doesn't look too difficult, so Phoenix III will be it. At the moment SHMBO is holding me back because she wants our owner builder project finished first. 2 and 1/2 years to build a 4 beddy house, garage and workshop, and it is still not finished. Building a boat is a relatively small project compared to that! A heck of a lot cheaper and more fun as well.