Another instalment of the epic is now posted.  www.anniehill.blogspot.com

My main point is that when a project - any project - drags on and on, taking much longer than the original time plan, however long that was to be, then it's much more likely to be overtaken by Events, on a global, local or personal scale. The goalposts are very much more likely to be moved, the longer a project lasts, and there's no arguing with that. Current example: we are into a global pandemic, and everything is up in the air for everyone. When the dust settles, it's not clear to anyone what the "new normal" is going to be like. So imagine, for example, building a very large voyaging boat over a long time scale, only to find that voyaging widely will now become so onerous that it no longer seems like the excellent way to spend one's life that it did a decade ago.

So no, Annie, I'm going to stick with the advice to be brutally honest with oneself about what can be reasonably attempted, with the available resources of all kinds - time, money, skills, energy, strength, materials, space - within the time span of two years. That applies just as much to fitting out a bare hull, refitting accommodation or simply converting to JR as it does to a complete new build. If that means only a small simple boat, not a large complex one, then so be it. The journey is more likely to remain as enjoyable as the initial dream promised that it was going to be. and, of course, the journey is more likely to end at the planned destination. 

I'm not sure I could be described as a serial boatbuilder.  I happily assisted on the first, was dragged screaming and kicking to the second, and have only actually been credited with building this one!  However, what may be a self-evident truth to The Great One, is not so to everyone.  I know lots and lots of boatbuilders who have thoroughly enjoyed the several to many years they have put into the project.  Not everyone can afford to employ labour and buy components, not everyone wants to use the winter to do other things than build their boat.  Many people enjoy the journey as well as the destination: there is romance in creating a boat as well as in sailing her.  Indeed, if you don't enjoy the journey then you are really wasting your time.  How annoying to pop your clogs before launch date having resented the effort spent in the previous few years - not of course, that you would know about it.

No David: your comments may be appropriate to someone who is desperate to get afloat and, for whatever reason, couldn't find a boat to suit, but if you are really so pragmatic about building and have money to employ labour and buy in, you would almost certainly, in this day and age, be able to find something that could be converted and would suit you almost as well.

Annie Hill wrote:

James: building a boat is sheer insanity. But then so are a lot of things that give us pleasure. From my experience, as someone who was wondrously inept with tools and even now has huge problems with converting two dimensions into three, the main drawback of it, is that you have to devote your entire life to the project, if you ever want to complete the boat. If you are used to woodworking and competent, this would possibly be less of an issue. However, unless you are single, it’s probably not the most sensible thing to do. A spouse would either have to be equally enthusiastic about the project or extremely tolerant to be happy with the work, time and energy building a boat requires. I’m happy that I decided to do this, but would be less so if it were as a way to go sailing, rather than a culmination of many happy years afloat. Even so, I’m pretty much over it and would like to get my life back.  Chafe shouldn’t be a problem with the rudders, because the rope doesn’t move.

Annie has shared some real words of wisdom about the boat-building gig. I once heard a saying; 'Fools build boats for other people to buy'. Building any reasonable sized boat takes hundreds or thousands of hours. Yes, a designer may say that the boat can be built in 800 hours, but even that is close to six months full time work. Building hours quoted are really just a stab in the dark, achievable perhaps with quick and nasty boat-building, or a highly skilled professional. For the rest of us building a boat is a real odyssey. So why do it? Perhaps it is the only way to get the boat you want for the money you have available. Maybe it is the satisfaction of creating something beautiful out of a pile of wood. For me it is the creative and technical challenge. Many construction dilemmas have been solved while unable to sleep at 1 am in the morning.

While many non-builders may have lots of 'advice' to offer, it is the person on the end of the glue stick who has got to come up with a balance of what is the perfect way, perhaps, of doing things, and the sheer reality of the fact that there is so much boat to build, so many details to figure out, so in the end the builder tries to achieve the best balance between time and skills and material available, and hopefully always motivated by the dream and vision of this boat creation one day actually being in the water, anchored up in some beautiful cove, or skimming rapidly along the coast. But sometimes us boat-builders ask, 'remind me again why am I doing this'

Anonymous wrote:

Eric: no the boards are not toed in. I guess I shall just have to develop my biceps.

I'm not sure what Eric meant there. Drawing a line from the mid point of the LE to the mid point of the TE of the board, it's at an angle of 1.6˚ to the centreline of the boat, so even though the flat outer face of the board is parallel to the centreline, there is actually that amount of toe-in. But this makes the boards harder to get up and down - in theory - because they are feeling more water pressure on them. In practice, it doesn't seem to make any difference. You use the weight of the board to get it down, when it's on the windward side, and the floatation to help to get it up as you tack, but in both cases, you do it when there is no hydrodynamic lifting force being generated.

Bonjour Annie and David

I will take as support the figure joined.


For the cambered sail the figures shows that, in this example, the angle of attack that gives a 0 lift force  is - 3°.

So to have no hydrodynamic drift (or opposed drifts between the two lowered dagger-boards) while motoring or sailing downwind the dagger-board should be toed in by 3°.

If you don’t toe in the dagger-board, when you are leaving your morning with a significant current, when you try to lower the dagger-board, you’ll have a lateral force, a drift, that will apply an horizontal torque (the dagger-board can not rotate into the case) on the dagger-board that tends to squeeze the dagger-board (as when you want to rise or lower a dagger-board in a dingy while sailing windward).

On other issue is that, when you are sailing headwind with both dagger-board down, if the dagger-board are parallel, if the drift is, let say 5°, the windward dagger-board (if down) will have an incidence of -5° + the 3° of offset and it will work « inverted » from - 8°. The profile doesn’t work properly at negative angle and it creates drag.

On an asymmetric profile, the reference cord is the cord associated with the O lift. That cord should be parallel to the boat axis.

For SibLim it might be possible to twist the dagger-boards in there cases by having a difference in thickness in the HDPE wedges. I don't know what profile was chosen but normally a few degrees of toes in should be enough.
Eric