Teaching at The Wooden Boat School Tradional Modern Oar Making

After work at Shaw and Tenney, I had my debut teaching job at Wooden Boat School. One of my favorite (and most labor intensive) specialties is oar making, so I was to teach the traditional way and the modern way, using composite blades. Each students chose an oar type of their choice to fit a boat they had or wanted to have. We had everything from 7 flat blade Spruce oars (for a Nutshell Pram) to laminated plywood spoon blade sculls to a Greenland style kayak paddle.

 

We were able to get out for two solid rows where CLint coached some fixed seat rowing and we all just enjoyed learning how to use oars and be comfortable in rowboats. We were able to use the schools fleet of rowboats, including this Joel White Shearwater.

 

Students quickly learned that oar making is mostly a wood removal activity, but they also learned some of my tricks, like adding decorative laminations on the outside of the upper looms. They also learned that there is a bit of engineering and art in making oars. Because we were able to get on the water, we also so the clear link between how we shape oars in the shop and how they react on the water.

 

Finishing oars after sanding is as much work as shaping them. One of my big pet-peeves is that oars are balanced and we spent a couple hours balancing everybodys oars with a little lead in the handle. It does not make the oar heavier, effectively, because the oars weight is on the gunwale. Therefore, it is the balance that makes oars feel lightweight. Leathering the oars is a project as well as sealing and varnishing. Everybody left with the oars largely done. One student had a good challenge. He brought in a pair of hollow sculling oars and wanted to make a replacement (or back up) pair in a week. So, we made the loom solid, sized down, and laminated a pair or plywood blades much like I do in my shop for customers oars, over a laminating jig. The blades are glued on the shaped loom and the finished result looks like this, and I might add he is very happy with them. In fact they are no heavier than the original, hollow sculls!

 

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Bow Transom and Cabin Top on Whimbrel

The matter of the bow transom on Whimbrel has stirred up some discussion over the last couple of days - see this post for information.

In the drawing above, you may be able to see that Ive drawn in three separate waterlines with accompanying displacement number attached. The upper waterline shows the displacement (952kg/2094lbs) with the water just touching the lowest point of the bow transom.

Here is an interesting comment from Rick Hayhoe: -

Phil Bolger sometimes said or wrote the strangest things. I have to point out the fact that you dont make the boat faster in any practical sense by drawing out the waterlines to the full LOA, leaving the boat just whacked off in a plumb scow bow that touches the water, or nearly so, at rest. What you do is create a monster that will misbehave in the slightest seaway and almost any wind.

I very much like the concept Ross is promoting in Whimbrel. Ive admired the design since first seeing it almost a year ago, but I certainly would make the boat eighteen inches or two feet longer at the forward end without changing anything else, getting that scow bow up, well out of the water and raked a bit more. Just imagine for a moment the danger of broaching on a downwind point of sail with following sea and opposing chop set up by a rivers outflow agains tide and wind, with that scow bow slamming into the chop and the following waves trying to push your stern ends around. Those are conditions one can expect to encounter routinely when entering many estuaries, let alone the conditions encountered while struggling in a squall or making for home in suddenly rising stormy weather.

Living as I have for many years in Asia, I have had the opportunity to look closely at a variety of scow bowed Asian sailing and motoring craft. Generally, you find that either the bow transom is raised well above the LWL or it is raked well aft. Some are built with a profile like a garvey, that is, raked and rounded, cross planked, to recede as they approach the LWL. In most cases, some compromise has been made in order to reduce the impact of the transom or scow bow against wave and chop.

Bolger was a brilliant designer, but he had a tendency to paint himself into the damnedest corners, and he was stubborn enough to stick to his pet theses no matter what. You have to admire most of his work, perhaps even his stubbornness when he was right, but youd better take some of his philosophizing with a grain of salt. Boats move through a constantly troubled and dynamic pair of fluids that make up one of the least forgiving environments on our planet. You flout at your own risk the limits and dangers they pose.

Rick Hayhoe


I estimate that a hull built from 600kg/cu.m plywood (a conservatively heavy estimate based on the weight of all the ply in the boat and then doubled to account for timber components, glass, epoxy and rig etc) would weigh about 314kg/691lbs. Add to that 240kg/528lbs for crew and gear and you end up with a displacement of 554kg/1219lbs fully loaded displacement. This is a conservative figure which I believe would be reduced significantly in reality.

Below is a perspective and a lines plan showing Whimbrel at the maximum displacement in salt water, and Im reasonably happy that the forrard sections are buoyant enough and shaped well enough (in terms of rocker, distribution of volume, and chine shape) to prevent the disasterous behaviour that Rick predicts. I may well be proven to be wrong, but after having modelled a number of other hull shapes at 18 6" length on deck and with a raised, smaller bow transom, I have elected to stay with the design as drawn at 17 length with the big bow. Storage and building space is a real issue for many people and I was trying to get a roomy and capable boat without excessive outside dimensions. There is no such thing as a perfect boat!

By the way, the bow transom is set at 65 degrees to the waterline, which is a long way from being plumb.

A perspective of Whimbrel showing the waterline at maximum displacement of 554kg/1219lbs in salt water

Whimbrel lines plan at 554kg/1219lbs displacement

Robert relied to the post yesterday regarding his question about sleeping space: -

Ross, I can see why you were taken with the concept. It sounds as if much thought has been given the design. I appreciate the amount of interior room designed in. Is there to be a slot top or more enclosed cabin? If designed to be totally roofed over, could the cabin be modified to add a pass through slot? It is very hot in Florida much of the year and the slot top cabin seems to offer greater forward access.

This is an interesting subject, and I had been giving it a lot of thought myself. You see, I cant stop fantasising about building boats for my own use, and Im quite taken by Whimbrel. While dreaming of the boat, I had decided that I would modify the cabin top if I built her for my own use, and that I would use a Birdwatcher-style slot-top. However, thinking that the majority of the buying public would prefer a conventional companionway with a sliding hatch, that is what I drew.
My opinion is that the slot-top is a superior option for this size of boat, allowing for better ventilation, unlimited headroom, and secure footing right up to the mast.

Just for interest - no plans available in any form - here is a twenty-foot boat I drew up for fun, to visualise a full Birdwatcher cabin on a nicely shaped conventional hull. She has got very firm bilges so that a person can sit comfortably out at the sides.

20x 6

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NEW! Drake 19

On the Drawing Board

New Drake 19 for tandem rowing, cruising and expeditions

For Fixed Seat or Sliding Seat Rowing

This new version of the Drake Rowboat -- my first design/build project -- really combines all that I have learned as a designer and rower and builder over the years. She is intended with the following brief:

-- fast, stable cruising rowboat

--capacity for two people and gear

--fixed or sliding seat capable

--can sleep aboard on platform under a tent 

--sailing downwind is possible

Drake 19 modeled in Rhino

An important aspect of the boat is its simple sliding seat system : 7/8" o.d. stainless steel pipes run for and aft with 15" of separation on center. The pipes are integrate into the CNC cut structure. A plywood seat-roller floats over these pipes. Any oarlock system can be used, including leathered-round oars, Douglas oarloacks, C2 oarlocks, or the folding outriggers by Shaw and Tenney. However, I think for voyaging in open water that oar-on-gunwale will be the best way, using traditionally leathered oars in horn-oarlocks or to go with pinned oars. I do think 9-9 1/2 oars would be fine for experienced rowers, using folding outriggers to get the spread for the longer oars.

Midship section of the Drake 19 showing the sliding seat system.

The floorboards are show both sitting on the inner keel as floors and raised up and sitting on the pipes to make an over 8 long sleeping platform that finishes flush with the side tanks. These side tanks double as a sleeping platform and as flotation, making the boat self-rescuable in a capsize. 

Keep posted for 3D work which starts very soon.

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Fleet Videos of performance with Two Different Motors

As some of you already know, Fleet is a planing-hull derivative of my very successful Flint design. For some background you can look at this post and at this post.

Fleet awaiting more trial runs

Fleet was designed from the outset to perform well in the very speed/length ratio spectrum in which normal planing hulls are at their worst. By that I mean the so-called "semi-displacement" or "semi-planing" range - widely thought to be in the S/L ratio range of 1.5 to 2.5.

Speed/Length ratio is basically the speed of a boat (expressed in knots), divided by the square root of the waterline-length (expressed in feet) of the boat. So let us take Fleet as an example: -

• LWL (length on the waterline) equals 14 feet
• Assume S/L ratio of 2.5
• Speed divided by 2.5 equals 3.74 (i.e. square root of 14 ft LWL)
• Therefore, Speed in knots equals 2.5 times 3.74
• Speed equals 9.35 knots (10.8 mph, or 17.3kph)

Now those speeds sound modest, but for a small boat like Fleet it represents a very satisfying speed indeed. More importantly, because this hull has been proportioned to operate within this S/L ratio, the boat trims well, instead of pointing her bow in the air like the standard planing hulls, which chew fuel at a high rate just to pull a large wake.

So far Ive been able to carry out several test runs in Fleet using both a 9.8hp Tohatsu two-stroke and a 2hp Honda four-stroke. The 9.8hp Tohatsu is based on the powerhead from the 6hp and 8hp models, so is suitable for this light-weight boat. My next test will be using a 4hp motor, which I think is about the optimum size from an efficiency perspective. In my part of Australia, 4hp (2.9kW) is the largest motor allowed without boat registration.

Here are two Youtube clips - firstly using the 2hp Honda, with which I achieved a consistent 7.9 knots measured by GPS with my weight aboard, and 7.1 knots with my wife joining me (she only weighs 60kg/132lbs. The 9.8 Tohatsu gave 15.5 knots (17.8 mph or 28.6 kph) with two heavy men aboard plus gear.

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Little Egret Launching

I am very excited to report that my Little Egret design, built by John Hockings, has been launched.

For those who dont know about this boat, you can read her history here, and here, and here, and here.

John has done a wonderful job of building his boat, showing that a determined first-timer who reads the correct books, and approaches things in a methodical manner can achieve first-class results. You can read about Johns building journey on his Woodenboat Magazine Forum thread here.

Launching day was overcast, rainy, and almost totally free of a sailing breeze. However, we did get a few short-lived breezes off the edges of passing showers, and were able to experience a little bit of resonable sailing - enough for me to form some opinions about stability and hull-balance. At this stage of the game I am very happy indeed with how the boat performed. In particular, I am delighted about the ergonomics of the internal layout. Here are some random photos: -

John just after arrival at the boat ramp. The rudder appears to be small, but it does comply with the rules-of-thumb regarding required area. However, I have given details for an alternative blade in the plans, which is somewhat larger. We had hoped that the use of end-plates would render this small rudder effective, and so far it seems to be very good. John has incorporated the old-time sharpie trick of being able to lower the entire rudder-post about four inches so as to drop the rudder deeper when clear of shoal water.

The hull-form of Little Egret is a cross between a sharpie and a dory, with a bottom panel wider than a pure dory, and with more flare in the topsides than is common in a sharpie.

Although it was early in the day, John and I indulged ourselves in a celebratory shot of rum and coke before the launching. That is John on the left, and a very nervous me on the right!

Moments after launching, sitting high on her lines as she has no load on-board. You will notice that she is very slightly down by the head, which is what we wanted, because the addition of crew weight should get her sitting level if my calculations are correct.

That is John and me on the very first sail. She proved to be very comfortable, with one person sitting beside the centreboard case and leaning against the forward coaming. The helmsman sits with back braced against the side-deck carling and with feet against the opposite side of the boat. This is a secure and effective way to travel. You can see in this photo that the fore-and-aft trim is just about perfect.

In from the first sail. The wind has dropped out, but we had encountered enough to discover that she sails nicely. That is me giving the thumbs up to my wife who took the photo.

This boat is very lean, and has fine entry lines

With two people aboard, the boat trims with the top of the rudder just below the surface.

John with his wife on launching day. His face tells a story about he feels...

Building plans for Little Egret are complete, but I wont be releasing them until a basic assembly guide has been written.

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Homeward Bound Los Cabos to Bahia Santa Maria

We stayed about a week in San Jose del Cabo at the luxurious and expensive Marina Puerto Los Cabos. Actually it’s not really luxurious. It doesn’t have a pool or much in the way of amenities for cruising sailors. Instead it caters to sportfishermen and mega yachters, a totally different type of clientele. It is very well maintained and has a nice little open air restaurant where you can get a hamburger for only about $13.00. That’s dollars, not pesos. The marina is beautifully landscaped and the docks are perfectly maintained, while the staff is mostly quite friendly and helpful. On the other hand, it has a sterile, soulless ambience along with plenty of security. I credit this to the mostly absentee ownership of the boats that call this place home. Of the hundred or so boats in the marina there were only five or six sailboats, most of which had people living aboard who were, like us, simply waiting for a weather window to head north to the US.

While we waited for the window to open, we spent a little time preparing the boat for the arduous 900 mile trip up the outside coast of Baja, but there really wasn’t much to do, as Finisterra was pretty much ready when we left La Paz. I had the bottom cleaned, changed the fuel filters and gave the engine a thorough inspection because we expect to be motoring or motorsailing for the nest 900 miles. There are very few places on the outside of Baja that have fuel or any kind of marine services so we want the engine systems in tip top shape. We also want the sails and rig to be in top form. There was nothing to do in that respect except give it all a thorough once-over. The only thing on the to-do list was to make a set of sail ties for the reef points. With all that done, we spent the rest of our free time checking out the beaches and hanging out in the very upscale environs of San Jose. It really wasn’t a very fun place to be and I confess that I checked the weather forecasts several times a day, looking for the first opportunity to get out of San Jose.

One of the new “attractions” at the marina is a Dolphin Discovery exhibit. It consists of three or four large pens next to the marina where they keep a half dozen or so dolphins in captivity. Tourists pay for the experience of getting into the pens with the dolphins for a personal encounter. We walked past the place several times in the early mornings, before the customers arrived and watched the captive dolphins swimming around in the pens while the “trainers” got ready for the day’s show. The poor dolphins looked pathetic compared to the exuberant ones we always see in the wild, and the whole concept of keeping these animals in captivity for profit disgusts me. I hope you never pay to pet a dolphin.

My primary sources for weather information are Predictwind and GRIB files. GRIB’s provide a good overview of winds in the region while the information from Predictwind is more detailed and specific. By Monday, June 2nd, the forecast started looking good for a Saturday departure, but as the week wore on, the forecast for the area around Cabo began to worsen. So we could either leave on Friday morning or wait for the forecasted adverse winds to pass by, which could be another week or more. We decided to take advantage of the current conditions and quickly checked out of the marina and got underway at 0930 on Friday, June 6^th, bound for Bahia Santa Maria.

The wind was light when we left San Jose but quickly built to 20-25 knots on the nose as we approached the Cape. In the twenty miles between San Jose and Cabo San Lucas the sea temperature plummeted from 83 to a surprising 68 degrees and we prepared for a chilly passage. But after rounding Cabo Falso, the last point of land before we could turn northward, the wind began to ease and the sea temperature rose to a much more comfortable 77 degrees. For the rest of the day and throughout most of the night we motored in balmy seas and a light wind. It was still on the nose though.

Finisterras route from San Jose del Cabo to Bahia Santa Maria

That night there was a waxing gibbous moon amid scattered clouds until around 0200. After the moon set the overcast sky cleared and we were kept company by the vast Milky Way, with Polaris, the north star off our starboard bow. The next day we continued in lovely light conditions until around noon when the wind and seas built. By 1500, when we arrived at Bahia Santa Maria it was again blowing 20 with a bumpy sea throwing spray over the dodger.

We are anchored in the northwest corner of the bay now. The wind is still blowing hard outside the bay, but I expect it to lie down a bit this evening. If it does, we’ll get underway around midnight, and head toward Turtle Bay, 220 miles away.

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Build a Model

The vast majority of my plans customers seem to be first-timers, and the building process - particularly visualisation - can be quite intimidating. Without any shadow of a doubt there are three primary aids in making a good start: -

• reading the correct text books (be extremely cautious about internet forums);
• spend plenty of time studying the plans;
• build a scale model.

The first two are self-explanatory, and I provide a recommended reading list with my plans, and try to make the plans detailed, supported by a comprehensive set of instructions.

Phoenix III plans - 30 sheets of A3 drawings and 50 pages of illustrated instructions.

Making a scale model is relatively simple if you follow the plans of the full-szed boat. The model doesnt have to be a masterpiece, but should follow exactly the sequence of constrution as specified in the plans.

Sometimes I build an exact replica using scale thickness plywood and scale thickness lumber of the same density as the full-sized boat. This allows me to test trim, stability, flotation and other elements of the design. At other times, I model only a section of the boat to examine things such as panel developments and curvature.

Hull panels for my Three Brothers design cut from 1.5mm Hoop Pine marine plywood to produce a 1/8th scale model.

Scale stitch-and-glue process

Hull panel developments being tested.

Anticipated shape confirmed as being developable

Sometimes people find it difficult to locate scale thickness plywood, but using balsa or other timber can still produce a worthwhile model for shape visualisation, and to help one understand the construction process.

Dan Taylors model of Phoenix III

Another photo of Dan Taylors Phoenix III

My good friend Doug Laver is building a model of First Mate just for the fun of it. He intends sailing the boat using radio control, and has replaced the centreboard with a ballasted fin keel to make up for the lack of crew weight out on the gunwale.

Dougs First Mate parts cut at 1/5th scale using plywood

Lots of little clamps in use

Ballast keel inserted in centreboard case from below

First Mate waiting for her lead ballast and her rig

Modelling may appear to be a time-consuming business, but in the long run it usually saves time - and it is fun!

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