A Seil in California

[pez_leon]

This thread will document the build of a Seil 18, designed by François Vivier.



Design considerations:
Until a few months ago I was pretty set on Vivier's Stir Ven 19 (Open Version). Then, my boys got old enough to join in on some of our adventures, and my perspective shifted.



I realized that it'll be many years before I want to take either of them out in a small boat in any kind of wind on my home waters of San Francisco bay. Once they're old enough for the bay, they'll probably want to sail their own dinghy with a class or a club. On the other hand they're already old enough to play around in our local lakes, estuaries, and rivers. And really, that's where I like boating best. Here's the manager out on a mountain lake last weekend (full thread here: http://forum.woodenboat.com/showthre...t-camping-trip)

[pez_leon]

Design brief:
I wanted a boat that was:
Small enough to comfortably launch, row, and sail singlehanded;

Image: Ben Ullings / F. Vivier

Well thought out enough to allow comfortable sleeping aboard;

Image from Bateau en kit; notice the floorboards raised to thwart level for sleeping platform.


And designed for self-recovery after a capsize. This video is the only capsize test I can find, and obviously it's not under real conditions, but I'm cheered by the relatively high freeboard of the swamped boat. I think I could bail that out and keep sailing.


I wanted plenty of room for me, the manager, and the supervisor, both of whom will only grow.

Image: F. Vivier


Image from Bateau en kit

And finally I wanted something I could build this century - between work and these kids, I don't get much time in the shop, and my previous boatbuilding experience is small. Vivier has given lots of though to how this one comes together.

Image: Duckworks/ Ben Ullings

[pez_leon]

Known limitations
All boats are a series of compromises. What am I giving up?
Well, there's that pram bow. I imagine that'll earn some questions from yokels.

Image: Bateau En Kit

The forward sections of the hull are notably full. I'm told this will obstruct in a chop.

Image: Ben Ullings / F. Vivier

And I'm ready wet ride in any kind of rough weather.

In short, this is not a boat I'll sail across the Bay on the afternoon of July 4th (or any other day). That's OK with me. Northern California offers plenty of quieter backwaters.

[pez_leon]

I'm still in the very earlist stages of building. The plan is to first build all the small parts, then build the hull. I'll need some kind of temporary shelter for the duration of the planking and fit-out process. My spouse has very generously ceeded a good chunk of the backyard for this; I intend to colonize it for the shortest time possible. For the next year or so it's fiddiler work on pieces that can be stowed away until needed.

First, oars, centerboard, and rudder. I had some spare 8/4 ash lying around. Three and a half hours got out enough staves to make four oar looms, four oar blades, and the centerboard and rudder blanks.


I've heard so much about ash oars, but I've never used a pair (I'm not even sure I've seen a pair). I'm making these to Vivier's specifications so that I know they'll fit in the designed onboard oar storage spacces. I figure they'll be heavy but durable. At the moment they're just slightly over the designated scantlings (to allow a bit of room for wood movement before final shaping).


My plan is to get them down to the specified dimensions, then test their flexibility as demonstrated by Rick in this thread:

This is my deflection measuring set-up. If this thread suddenly goes dark it is either that my wife has seen what I am doing in her kitchen, or that Mike has seen what I am doing to his oar .



From R to L: Pocock scull, my homemade oar with 1.1" fiberglass shaft, and DF/redwood blank. The weight is a bucket filled right at 10.0 kg.

Based on the results of that test I'm considering shaving them down further until they show the desired flexibility - like tuning a wooden bow. This means shaping them below specified dimensions, which I would justify on the assumption that ash should be stronger than the specified spruce/fir. Any advice?


Up next is gluing on staves for oar blades, and gluing up the centerboard and rudder blanks. I would have gotten there today but for the supervisor deciding we were done in the shop.


Looking ahead I'm sourcing lumber yard fir for the mast. The plans call for a 60-70 mm sheeve at the masthead. On a lark, I turned one on the lathe from some HDPE I had laying around the shop. It came out well enough. Even better: according to people who know what they're doing, it should work See here: http://forum.woodenboat.com/showthre...PE-for-sheeves

[Dryfeet]

Vivier’s Seil is an attractive boat. The thing about a pram bow is that, effectively, you have a bigger boat but just one with a foot or two lopped off. It’s one I’d consider if I had a use case for an open sail and oar boat. Of course an Arctic Tern might possibly win out.....

[pez_leon]

Last post for tonight. For the sake of completeness, here's the designers sketch, including the particulars:


Hull Length 5.4 m
Waterline Length 4.2 m
Breadth 1.64 m
Weight Ready to Sail 210 kg

[FF]

Nice to see Ben Ullings boat here, as I made the sail for him. He was not to keen on the big boomless mainsail and I suggested a slightly smaller balanced lug would be easier. I used the dimensions of a Ness Yawl mainsail but the boat proved to be neutral on her helm, sometimes she had lee helm. Ben did not like to add a small mizzen, also my suggestion, and asked Ms.Vivier to design a new balanced main with a boom, that I subsequently made, and that is the sail in #3. Her CE is in the right place. I used her old sail then for my own boat, Lucia, and found the CE also a bit far forward so I added a mizzen. Must make a few mistakes to learn. You can find more details from Bens Le Seil in my blog, and also the link to my video, Two luggers at play, on Youtube.
I wish you pleasant building. Frank
www.oarandsail.nl

[timo4352]

Another that will be following your build.
Thanks for taking the time to post.
Good luck.

[The Jeff]

Looking forward to following your progress!

[stromborg]

Seil is a cool and unusual (at least around here) boat. Looking forward to following along on your journey.

[Thorne]

Great choice, hope to see you on the water sometime reasonably soon! You may want to join the local Traditional Small Craft Association (TSCA) and get on their groups.io list -- they'll be very helpful in finding Bay Area sources of materials as well as having centuries of combined boatbuilding experience.

https://www.tscasacramento.com/

My fave photo of Seil -

[FF]

Great choice, hope to see you on the water sometime reasonably soon! You may want to join the local Traditional Small Craft Association (TSCA) and get on their groups.io list -- they'll be very helpful in finding Bay Area sources of materials as well as having centuries of combined boatbuilding experience.

https://www.tscasacramento.com/

My fave photo of Seil -

The first Le Seil I saw was built by Francois Lelievre, I think with larch planking, in the Dorestad raid. This might be her. Frank
www.oarandsail.nl

[rgthom]

Great choice of Seil, am looking forward to following this thread and hopefully meeting up out on the local waters soon.

A comment on oar flex: the oars I built on the (interminably long) thread you referenced are very soft on the Concept II flex scale. The earlier ones are so soft they are way off the scale. I actually like the softest ones best for all day rowing this kind of boat. They soak up any jerkiness and give an easy kick at the end of the stroke, very forgiving for my old back and arms. I do not notice any loss of speed compared to stiff oars, at the steady pace of a loaded camp cruiser.

[pez_leon]

Great to hear from all of you. Frank, your comments on the possible sail plans are interesting. Vivier includes both the boomless sail plan and the sail plan for the balanced main with boom. I haven't quite made up my mind but am leaning toward the boomless misainier. What I read about the misainier falls into two camps: people who haven't used it, who express trepidation about handling the large sail and moving the mainsheet in a jibe; and people who have used it, who laud its simplicity and performance. Anyway, thanks for sharing, and thanks for the link to your website. Your video is beautiful.
Rick and Thorne, thanks for the local welcome. I'll look into the local TSCA for sure.

James

[pez_leon]

Oar making continues. When I started this part of the project, I told myself I was not going to overthink this pot of beans - just make the oars shown in the plans and get on with building the rest of the boat. Vivier's oars are flat, with long, narrow blades. I've seen similar styles called "workboat oars" on this forum. They make sense to me for this boat, which I hope to sail more than row and in which they'll be trod upon, smashed into rocks, and otherwise abused.
I want some numbers I can use to compare these oars to others, so I measured the stiffness of the looms as per this sketch from Concept 2 (also shown by Rick in a post quoted above):

from https://www.concept2.com/oars/oar-options/shafts/stiffness

The many differences between these flat oars and the pictured hatchets complicate meaningful comparison. For one thing, the blades on these flat oars are proportionally longer than on spoons or hatchets, meaning that hanging the 10 kg mass on the loom-blade intersection bends much less of the loom, and leaves the most flexible part of the oar (i.e.the blade) unflexed. Likewise, hanging the weight at 150 cm from the oarlock (as shown above) lands the mass in an arbitrary spot in the middle of the blade. There's really no "right" place to hang the mass on a flat oar that corresponds to the place above. I'm including these numbers only as a record for myself or for someone who wants to make similar measurements on long-bladed oars.
With the 10 kg mass suspended at the loom-blade intersection (i.e. where the oar will widen to form the blade) the loom deflected about 4 cm


With the mass suspended at 150 cm from the oarlock (as in the diagram from concept 2) the loom deflected by 12 cm - but don't make too much of this, because we have yet to glue on the cheeks that will widen the end of the loom into the flat blade of the oar.


So what's called for is to get the oars into something closer into their finished shape before making any more measurements. I glued on half the "cheeks" that will form the oar blades this morning:

Once the epoxy has fully cured I'll bandsaw those down to the taper already present in the loom, then glue on the other cheeks and repeat.

I glued up a long laminated blank (or at least the two halves of it that will be narrow enough to pass through my planer) for the rudder and the centerboard. Vivier's latest plans call for making these parts from laminated 12 mm ply, but he notes that timber is also a good choice. The staves for these came from some slightly wonky ash. I shuffled, alternated, and flipped them as best I could before lamination. I'm still not 100% confident that this blank will stay true enough for centerboard use. The plan is to get it flat and then watch it for a while.


James

[Thorne]

Looking good, although it looks like your initial determination to not overthink the oars may have slipped a bit... ;-)

Since ash isn't known for having much rot resistance, you may want to glass the CB and finish it bright. That will make it much easier to spot any damage to the wood after a few years. My CB's always seem to have the dual function of depth finder as well as foil.

[pez_leon]

More oars! Both cheeks are glued on to the already tapered loom. The same taper is then bandsawed into the cheeks. The tapered loom serves as a guide to bring the cheeks into plane.


The scrub plane makes quick work of this job. I am constantly surprised by how useful this tool is. When you're using it right, it makes an unzipping sound as it breaks back these fat shavings.


All four oars are planed smooth and ready to be shaped. The template makes quick work of marking out.


But where did the template come from?


The patterns arrived a few days ago from France. Included on this mylar sheet is a full-scale drawing of the oar blade. Once the pattern is unrolled and the builders are silently cowed by the scale of the thing they have committed to make, one need only slip a piece of scrap wood behind the mylar and trace the desired shape with a pounce wheel. Voila- your template is laid out in the form of tiny pinpricks. I was curious to see how accurate I could make this step (it's going to matter a lot more when I'm laying out the strakes!) I'm reasonably pleased with the results. I think I can do better next time if I can convince my manager not to repeatedly get his head, feet, and arms between my eyes and the pounce wheel. Or to not dance a jig on the slippery template.

[pez_leon]

The oars finally look a bit like oars. This is the last chance to shape them together.


The blades are to be shaped from a rougly trangular cross-section where they meet the loom into a flat rectangular cross section at the tip of the blade. Many saw kerfs down to layout lines allow accuracy and prevent uncontrolled splitting.


The mallet is stolen and banged against the workbench while the manager belts show tunes at full volume.

[nrs5000]

The mallet is stolen and banged against the workbench while the manager belts show tunes at full volume.

That's awesome, my boys appropriated my mallet this weekend to reenact scenes from Asterix the Gaul!

[pez_leon]

Since ash isn't known for having much rot resistance, you may want to glass the CB and finish it bright. That will make it much easier to spot any damage to the wood after a few years. My CB's always seem to have the dual function of depth finder as well as foil.

I like this idea a lot. I, too, get double duty from my foils.

[Michael_Owen]

I used ash just as you did for a daggerboard and it has been great. A bit different, since it is not submerged all the time. But if you're trailer-sailing it should be fine.

Mike

[FF]

With such beautiful oars you will never need an outboard and your boat will look so much better.
Frank
www.oarandsail.nl

[callsign222]

This is one of my most favorite Vivier designs. If I was living further south in quieter and warmer water I’d have this boat. Maybe even here, for Maine, maybe... but it was right on the line for my kind of sailing up here which can be rowdy with consequences and I passed. It’s the consummate river boat, I grew up on a large river and man, whoa she’d be perfect there.

damn I love this design!

Rig wise maybe contemplate a standing lug with a spritboom. You’d get the tensioning aspect of a boom with the boomless lug versatility. It will be lighter and easier to handle than a full boom. Some days you could skip the boom if you wanted. Vivier might be happy to draw you one. See: Ilur Waxwing for reference. Carbon helps here with friendliness immensely.

[pez_leon]

Lots and lots of carving:





Carving handles. John DeLapp's excellent oar plans refer to this shape (defined by the overlapping circles just visibly scribed in the end-grain of the handle) as a "modified norse grip". I made my last set of oars to his plans and liked it.





Yielding something still unfinished, but oar shaped.



James

[pez_leon]

Pictured above is the first pair of oars. This boat has two rowing stations and thus calls for two pair. The second pair will be a bit different. Why?

it looks like your initial determination to not overthink the oars may have slipped a bit... ;-)

That's why

First, a disclaimer: Don't take anything below as a reflection on Mr. Vivier's oar plan. Any issues I flag were likely a result of my decision to change things.

As designed, the oars for the Seil 18 ride on thole pins.

Picture not mine, found via google images - Fabianbush.com?

I'm sure this works great, but I figured I'd stick with an oarlock system I know and love. I'll install open-topped oarlocks on this boat. I do occasionally feather my oars and I like to change my hand position from a full overlap to something futher apart, which thole pins wouldn't allow.
Vivier's plans call for mostly square sections in the loom. So that I could use oarlocks, I slightly reduced the section of the loom from the oarlock to the blade and then rounded them so that they could move within the oarlock. That's a change that could affect the balance of the oar.
The balance of the oar is also affected by the shape of the loom inboard of the oarlock. However, this "inboard portion" ended up really small in the pair of oars pictured above because the Seil is designed to allow two smaller rowers to row side-by-side at a single station. If I were building this boat a few years ago I would briefly smiled at this idea before throwing it out and making what I thought would work best for me alone. Now, I have two rapidly growing oarsmen to consider, and if I stretch my imagination I can just barely imagine them pulling sweeps. Maybe even pulling sweeps while I idly drink coffee and admire the landscape. If these strapping lads are to row abreast, they'll need to extend each oar pretty far out of the boat, meaning that I'll place the buttons awful close to the handles, meaning that there's very little inboard loom to counterbalance the blade. As a result, these oars don't balance as I'd like.



Pete Culler specifies that oars should balance within 12" of the oarlock. John DeLapp calls for a hand balance weight of 1 3/4 lbs. These oars balance around 22" from the oarlock (assuming one is rowing with a one-hand overlap) and have a hand balance weight somewhere around 3.5 lbs. Not perfect. On the other hand, I do so like making oars. I won't feel too bad if I need to make a new pair.

Because I'm making two pairs of oars for this boat, I'll make the second pair balance properly for a one-hand overlap. I'm taking the looms down to round now. It's my first time using a spar gauge and I'm pleased with the results- and also happy to make my learner's mistakes here and not on my mast!

James

[pez_leon]

Rig wise maybe contemplate a standing lug with a spritboom. You’d get the tensioning aspect of a boom with the boomless lug versatility.

Thanks for the suggestion. I don't know enough about rigs to properly weigh the benefits of "the tensioning aspect of a boom". Would you please elaborate?

James

[callsign222]

Boomless sails are floppy and sometimes can be difficult to manage depending on point of sail and wind strength. But perhaps the sailor isn't interested in a larger cumbersome boom at head level, (though two Seils pictured above have traditional booms.) Enter: Spritboom. It's lighter and smaller, managed with a snotter, which tensions the sail, and is located higher on the sail. For me, it's the best of both worlds.

Just an idea.

[WI-Tom]

Boomless sails are floppy and sometimes can be difficult to manage depending on point of sail and wind strength. But perhaps the sailor isn't interested in a larger cumbersome boom at head level, (though two Seils pictured above have traditional booms.) Enter: Spritboom. It's lighter and smaller, managed with a snotter, which tensions the sail, and is located higher on the sail. For me, it's the best of both worlds.

It's always interesting to hear other thoughts about this. My own views have evolved now in my 4th year with my Alaska with its boomless standing lugsail. A few thoughts:

A. I think a boomless standing lug might be the perfect rig if you are looking for a boat that will disallow "type A" behavior, such as fiddling with adjustments and tweaking things. There's only a sheet, and a downhaul. That's it. If you're the kind of sailor who finds that comforting, a boomless sail may be right for you (it sure is for me). If, on the other hand, you find yourself thinking "There's a lot of twist in that sail, and I can't control it!" (while wishing you could)--well, a boomless rig is probably not for you.

If, on the other other hand, you notice the sail twist and think to yourself, "There's a lot of twist in that sail! It's spilling enough wind that I don't even need to reef quite yet," then again, the boomless sail may be for you.

B. As long as you get the sheeting point right, a boomless sail will perform well. You won't be able to let the sheet out much for downwind, but that doesn't matter. You'll be faster to keep it sheeted in a bit and tack downwind in a series of gybes. One of the most common justifications for a boom I hear is for downwind work, but I've concluded it just doesn't matter.

C. I haven't found my boomless standing lug to be floppy or difficult to manage--I'd be curious to here more about what you mean?

In very light airs for downwind work, I find I sometimes rig an oar to hold the sail out. Simple and easy to do, mainly to prevent the annoyance of constant gybing if you have to sail dead downwind (as I did last weekend while exploring a local creek). That's about the only time I can think of that a boomless sail might be described as "floppy." Usually it's enough to sit to leeward to keep the sail filled.

I think John Hartman's Ilur has probably hit on the perfect combination of sprit boom and boomless sail to enable fine adjustments and "type A" behavior. But one big advantage of a boomless sail is that it removes the ability (and thus, the need) to make those adjustments!

Tom

[callsign222]

Thanks for pointing this out.

Disclaimer to pez_leon: I am 100% Type A Sailor-Man and I view my sailing through the lens of racing Lasers, 420s, GIS's and other higher-octane boats. I demand efficiency and speed in the rig and abhor floppiness, which is undoubtedly subjective and relates to my past experience.

Traditional-ish hull with carbon spars, full battens, and spectra? That's me.

[WI-Tom]

Thanks for pointing this out.

Disclaimer to pez_leon: I am 100% Type A Sailor-Man and I view my sailing through the lens of racing Lasers, 420s, GIS's and other higher-octane boats. I demand efficiency and speed in the rig and abhor floppiness, which is undoubtedly subjective and relates to my past experience.

Traditional-ish hull with carbon spars, full battens, and spectra? That's me.

It'd be fun to go sailing with you sometime, and watch your furtive eyeballing of all the things I should be doing to maximize performance, but don't do.

And then see what happens when you take the tiller!

Actually, I'm sure there are things I won't even notice--we're often talking fractions of a knot, I'm guessing, for racing sailors. But it'd be interesting to see if you'd change anything about the rig and/or procedures to get the most out of it as is.

Tom

[John hartmann]

Just another thought to stir the pot a bit, would be an unboomed but fully battened standing lug, without the sprit boom. If the bottom batten is stiff enough, it would prevent the sail from developing deep draft when sailing down wind. Ben Fuller has such a set up on his Antonio Dias designed Harrier, Ran Tan, and it works well. I had Ran Tan in mind when I asked my sail maker (Stuart Hopkins, of Dabbler) to make Waxwing’s sails, and he suggested I experiment with the sprit boom, which I also find works well and is easy to live with. With or without the sprit boom, sheeting angles are important for best function, just as Tom said.

[pez_leon]

What a great discussion. Thanks Tom, John, and calsign222 for your thoughts on rigs. I'm convinced that the right rig boils down to the personality of the sailor. Maybe we need some kind of a personality test, something in the style of Cosmopolitan magazine. What's the right rig for a "Samantha"?
I'm leaning toward the unbattened boomless lug because I tend toward Tom's benignly apathetic style of sail trimming. What's more, the boomless rig is already drawn, and of the many options I think it'd be the simplest for me to sew from a sailrite kit.

James

[pez_leon]

I wonder if anyone might weigh in before I send a question off to the designer. I had an idea rattling around that I'd shape the foils in this boat to NACA profiles. (I've done it before for a rudder on a larger boat and enjoyed the process). Having read a bit more (including Alex Zimmerman's excellent article in this month's Small Boats Monthly) I realize that the factor limiting my ability to shape a hydrodynamic centerboard will be the board's width. The plans call for a board with a chord length around 35 cm. To make a NACA 0012 profile, I'd need a thickness of 12% or around 4.2 cm. That's about twice the specified board thickness.
I'm a neophyte and don't want to haul off and make major changes to a great design. Maybe a more traditional hull shape like this doesn't benefit from a hydrodynamic foil? If I did make the board twice as wide, I'd also need a wider CB case, a wider CB slot in the sole, and perhaps other changes. I'm sure each of these might have their costs, but if they're small enough they might be worth paying for increased efficiency. I don't plan to enter any races in this boat but I do enjoy making progress to windward in what at least feels like an efficient craft. If you have any thoughts I'd enjoy hearing them. Would you bug a designer about this idea, or would you just make the board as planned?

James

[John hartmann]

I would make it as planned. A “thin foil” with rounded edge and a taper over the trailing 1/3rd will be fine, and so will your windward performance.

[pez_leon]

Thanks John, that's reassuring. If it's good enough for waxwing, it's good enough for me.
My question is more academic than practical and I'm sure reflects my ignorance. It seems that "thin" (<1", or approximately 6% of cord width) centerboards are common in designs by Vivier, Oughtred, Lilistone, and plenty of other designers who are vastly more knowledgeable than I'll ever be. On the other hand, everything I find written specifically about foils suggests that a profile twice as thick or more would be beneficial. These designers obviously know what they're about, so what's the advantage of the "thin" board? If anyone wanted to opine I'd be curious to hear it.