Boatmik
4th July 2008, 01:55 AM
This was prompted by daddles on the general PDR thread.
The funny thing I was writing a reply for Luis Grauer who was asking the same question earlier in the day. While I was writing I thought, "maybe I need to put this info up somewhere".
The first question was to compare the sprit with the balance lug
I just downloaded the PDRacer plan for $20 (http://www.pdracer.info), and as we say here,esta absolutamente perfecto. Muchisimas gracias. So where do I look for your dicussions on the pros & cons of the lug rig? With all the writing you do, how do you find time to work/sleep?
The sprit rig is by far the easiest to make work well. and is much more trouble free for someone who just wants to put the sail up and go out. The mast is a bit long - but it goes on most car roofs with only a little overhang each end. YOu can get good performance without understanding much at all about sail setting.
http://farm4.static.flickr.com/3122/2394715811_c942f676e9.jpg
The lug rig is more compact but a little bit more fiddly in use. Not a lot - it still rigs quite quickly but it doesn't have the absolute trouble free feeling of the sprit. There is more work in making the spars. But they will go on a trailer without too much overhang and on a car roof with no overhang. You need to make quite a lot of decisions to get the rig to work really well - though my guides for both types will give you a head start.
This pic is of the launching of the first OZ PDR with the optional balance lug rig. I have put the full article up here (http://pdracer.blogspot.com/2008/07/first-oz-pdr-with-lug-rig-option.html). That is about 89 square feet of sail on that little boat folks. We have gone big because we know the OZ can handle 82 sq ft in the taller sprit rig fine and this lug can be reefed nicely.
http://farm4.static.flickr.com/3047/2633525904_9f49a2a358.jpg
Luis got back to me
I've owned a boat before, a Swedish Kings Cruiser(9m bermudian sloop), also a Snipe and a Lightning, but I've only sailed Gaff and Bermudian rigs.
Tom Jones highly recommends the srit rig(sail shaped like a gaffer), and you apparently prefer the lug, as does Ian Oughtred, So the question is "Where can I read up on the lug rig?"
I had planned the3 sprit rig for my Dobler, but I'm open to other ideas, and since dealing with you and reading your stuff, I'm leaning towards boatmik solutions, but I'd still like to rerad what I can. So where do I encounter your guides?
Howdy Luis,
I don't have it all in one place.
Some of the discussion is on this page
http://www.storerboatplans.com/Faq/tradrigperformance.html
But briefly - the reason bermudan rigs perform well is because they have a boom vang to control sail twist. Remove this and the traditional rigs that CAN control twist have a huge performance advantage. For example the Balance Lug was the premier racing rig in small boats, easily outclassing the gaff until the bermudan rig came along and extra bits to control the sail.
The rigs that can do this without any extra gear are the triangular sprit, the balance lug and the lateen.
I don't like the lateen a lot because as you reef the sail takes on a pretty weird shape that makes it hard to sail and control the boat. Like a low narrow triangle.
http://farm4.static.flickr.com/3221/2377188706_e7d37c084f.jpg
In a way the balance lug converts to a lateen as it is rigged - so I class them as close relations.
The triangular sprit is the most effective at preventing twist and is so simple to set up
The four corner sprit is a rig I have almost no time for. And in boomless configuration as per the pic below it is even more useless in performance terms - anyone who says that a boomless sail is highly efficient is either racing a super high performance racing catamaran with a curved traveller or ... is allowing the advertising prose to get ahead of the facts. Anyway ... there is a more detailed argument about boomless in the article I linked to above. There are good reasons to go boomless, but performance ain't one of them.
http://www.easthillboatshop.com/images37/1128catspawontrailor.gif
The other rigs can have sailshape and spar diameter set up to get gust response. That a gust comes, the spars bend a predetermined amount and which flattens the sail, reducing power. Then when the gust ends the spars straighten, the sail becomes fuller, increasing the amount of power the sail can develop. This allows the boat to accelerate freely in the gusts without the sailor having to do much at all.
The four corner spirt cannot do this at all - everything it triangulated and the mast bend has no control over the depth of the top of the sail. Also it is a total pain to reef because all the action is happening high above the deck. I think it is one of the most unhandy rigs ever developed. It's only real advantage in my books is it can spread a LOT of sail on a short mast.
Most who suggest other rigs are either working to criteria other than efficiency for the buck or have not spent much time carving his way round a racecourse in modern boats and is probably assumings that history is the best teacher.
There are some fine lessons in history, but as Henry Ford might have said if he had been a more reasonable man - Much of History is Bunk. And this is particularly in terms of what makes a boat sail well. Almost all advances have come from racing dinghies over the last 70 years.
I try to take the best of that progress and ally it with the traditional rigs that meet the same criteria as the modern ones. This cuts many of the trad rigs out of the list because they either cannot control twist or do not allow a dynamic interaction between spar bend and sail shape.
As far as Luis' question about getting sleep when I do so much writing ... It is 12.40am.
Best wishes
Michael Storer
The funny thing I was writing a reply for Luis Grauer who was asking the same question earlier in the day. While I was writing I thought, "maybe I need to put this info up somewhere".
The first question was to compare the sprit with the balance lug
I just downloaded the PDRacer plan for $20 (http://www.pdracer.info), and as we say here,esta absolutamente perfecto. Muchisimas gracias. So where do I look for your dicussions on the pros & cons of the lug rig? With all the writing you do, how do you find time to work/sleep?
The sprit rig is by far the easiest to make work well. and is much more trouble free for someone who just wants to put the sail up and go out. The mast is a bit long - but it goes on most car roofs with only a little overhang each end. YOu can get good performance without understanding much at all about sail setting.
http://farm4.static.flickr.com/3122/2394715811_c942f676e9.jpg
The lug rig is more compact but a little bit more fiddly in use. Not a lot - it still rigs quite quickly but it doesn't have the absolute trouble free feeling of the sprit. There is more work in making the spars. But they will go on a trailer without too much overhang and on a car roof with no overhang. You need to make quite a lot of decisions to get the rig to work really well - though my guides for both types will give you a head start.
This pic is of the launching of the first OZ PDR with the optional balance lug rig. I have put the full article up here (http://pdracer.blogspot.com/2008/07/first-oz-pdr-with-lug-rig-option.html). That is about 89 square feet of sail on that little boat folks. We have gone big because we know the OZ can handle 82 sq ft in the taller sprit rig fine and this lug can be reefed nicely.
http://farm4.static.flickr.com/3047/2633525904_9f49a2a358.jpg
Luis got back to me
I've owned a boat before, a Swedish Kings Cruiser(9m bermudian sloop), also a Snipe and a Lightning, but I've only sailed Gaff and Bermudian rigs.
Tom Jones highly recommends the srit rig(sail shaped like a gaffer), and you apparently prefer the lug, as does Ian Oughtred, So the question is "Where can I read up on the lug rig?"
I had planned the3 sprit rig for my Dobler, but I'm open to other ideas, and since dealing with you and reading your stuff, I'm leaning towards boatmik solutions, but I'd still like to rerad what I can. So where do I encounter your guides?
Howdy Luis,
I don't have it all in one place.
Some of the discussion is on this page
http://www.storerboatplans.com/Faq/tradrigperformance.html
But briefly - the reason bermudan rigs perform well is because they have a boom vang to control sail twist. Remove this and the traditional rigs that CAN control twist have a huge performance advantage. For example the Balance Lug was the premier racing rig in small boats, easily outclassing the gaff until the bermudan rig came along and extra bits to control the sail.
The rigs that can do this without any extra gear are the triangular sprit, the balance lug and the lateen.
I don't like the lateen a lot because as you reef the sail takes on a pretty weird shape that makes it hard to sail and control the boat. Like a low narrow triangle.
http://farm4.static.flickr.com/3221/2377188706_e7d37c084f.jpg
In a way the balance lug converts to a lateen as it is rigged - so I class them as close relations.
The triangular sprit is the most effective at preventing twist and is so simple to set up
The four corner sprit is a rig I have almost no time for. And in boomless configuration as per the pic below it is even more useless in performance terms - anyone who says that a boomless sail is highly efficient is either racing a super high performance racing catamaran with a curved traveller or ... is allowing the advertising prose to get ahead of the facts. Anyway ... there is a more detailed argument about boomless in the article I linked to above. There are good reasons to go boomless, but performance ain't one of them.
http://www.easthillboatshop.com/images37/1128catspawontrailor.gif
The other rigs can have sailshape and spar diameter set up to get gust response. That a gust comes, the spars bend a predetermined amount and which flattens the sail, reducing power. Then when the gust ends the spars straighten, the sail becomes fuller, increasing the amount of power the sail can develop. This allows the boat to accelerate freely in the gusts without the sailor having to do much at all.
The four corner spirt cannot do this at all - everything it triangulated and the mast bend has no control over the depth of the top of the sail. Also it is a total pain to reef because all the action is happening high above the deck. I think it is one of the most unhandy rigs ever developed. It's only real advantage in my books is it can spread a LOT of sail on a short mast.
Most who suggest other rigs are either working to criteria other than efficiency for the buck or have not spent much time carving his way round a racecourse in modern boats and is probably assumings that history is the best teacher.
There are some fine lessons in history, but as Henry Ford might have said if he had been a more reasonable man - Much of History is Bunk. And this is particularly in terms of what makes a boat sail well. Almost all advances have come from racing dinghies over the last 70 years.
I try to take the best of that progress and ally it with the traditional rigs that meet the same criteria as the modern ones. This cuts many of the trad rigs out of the list because they either cannot control twist or do not allow a dynamic interaction between spar bend and sail shape.
As far as Luis' question about getting sleep when I do so much writing ... It is 12.40am.
Best wishes
Michael Storer