Photos of a Good Flat Bottomed Skiff

Back in April I wrote two posts about flat-bottomed sailing and rowing boats (see Discussion About Flat-Bottomed Boats and Sharpie Hulls and Fine Sections ).

Things have been pretty hectic at our place since the disasterous flash-flooding which hit our area on January 10, 2011, but over the last few weeks Ive been getting back to work on some over-due jobs, one of which is a nice flat-bottomed skiff for a customer in Brisbane. She is a Jim Michalak-designed Mayfly 14 and is a good example of a well-designed flat-bottomed hull. The point to note is the relationship between the curve (or rocker) of the bottom when viewed in profile, and the curve of the topsides when viewed in plan-view. These two shapes, in combination, determine the chine-line, and the the flow of water around that chine. The aim is to reduce cross-flow to a minimum in order to minimise eddying.

A nice, simple boat, showing the pivoting leeboard, centreline hatches, and external chine log.

Many people find external chine logs difficult to accept, but they have some advantages. They are much easier to install on a boat which isnt built on a strongback, avoiding compound bevels and determination of length. In addition, they provide good protection to the chine, which is somewhat vulnerable on a flat-bottomed boat. Phil Bolger had a theory that if the hull was properly shaped, an external chine log may reduce drag, by delaying the point at which cross-flow occurred. In addition, I guess that they provide a bit of extra lateral resistance, which is good in a sailing boat.

Brutally simple pivoting rudder design which requires only one rudder cheek. The key is the amount of blade above the pivot point, as it provides support to the blade regardless of which tack the boat is on. The patch at the bottom of the blade is where Ive cast in a block of lead to sink the blade. It is covered with a small patch of 200gsm/6oz glass to prevent cracking between the lead and the plywood. The white is epoxy and sanding filler. 

Very simple, but rugged, mast step and mast partner, well braced by framing on the other side of the bulkhead.

Close-up of the mast step showing the very necessary drain hole to get rid of water in the step. This is all a bit rough at this stage, still waiting for some clean-up and fairing work.

Close-up of the external chine log, rounded over on both edges, and showing how Ive brought the epoxy/glass bottom sheathing around the bottom edge and up over the chine log. This is to protect the vulnerable edge grain of the 1/2" plywood bottom.

Outer stem made from a superb piece of Celery Top Pine from Tasmania. Hard, dense, and strong. Still waiting for finishing work and fairing.

Close-up of the external gunwale/sheer clamp, laminated from two beautiful pieces of Silver Quandong. Note how in a simple boat like this, there are plenty of places where the edge grain of plywood planking is vulnerable - this needs to be considered, with action taken to protect the edge. The edge of this plywood will be treated with three or four soaking coats of epoxy prior to being painted, but even then it will have to be watched in service.

Detail of the corner joints in the hatch framing. Once again, Silver Quandong

The single-sided pivoting leeboard allows for a clean and open interior. Although simple in concept, the leeboard design requires great attention from the builder when fabricating the leeboard upper and lower guards, so that the board is absolutely parallel to the centreline of the boat. Trickier than it looks!

A nice, simple, rugged boat. The external stem cap is yet to be trimmed, and at this stage Im planning on finishing it off with a Jonesport Cleat.

So, there you have a nice little boat. But you dont get something for nothing. These boats might be easy to build, but they consume large numbers of silicon bronze screws, and the structure is quite heavy. However, she should give long and trouble-free service, given that she is painted properly (she will be) and stored properly

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Good News

Clints design the Drake Rowboat, "A new take on the Faering for the modern oarsman" is featured in the 2010 Small Boats edition by Wooden Boat Publications. It is on newstands and it is a great issue. Click here for more info.

Clint is also a recommended US builder for Michael Storer boat designer and will be producing a line of high-performance rudders and centerboards using a unique foil template developed for small boats by Michael Storer with research done by Aerodynamicist Neil Pollock. In addition to high performance foils, look for tillers, Birdsmouth masts and spars, and a new oar designed by Clint employing carbon fiber blades on a refined Sitka Spruce loom. This new oar will be up in a few days, so stay tuned! You can see more about Michael Storers talk at my shop earlier in this blog site. Michaels website is http://www.storerboatplans.com/

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Some seriously good news

There be bigots assholes in Dent County Missouri, just some welfare for rich folks, and Im not quite sure the military and I share the same definition of the word humane...

Ive never been a big fan of carrying around a lot of pyrotechnics as things designed to explode/burn on a boat just make me nervous. A feeling underlined over the years by a too large number of incidents where flares became part of the problem rather than the solution.

Truth be told, flares scare me.

Then theres the ongoing need to replace your flares every couple of years... Yeah, I know flares have a three year lifespan but, try as I may, whenever I find myself needing to buy flares I only seem to be able to find flares with eighteen months or so validity.

Have I mentioned that flares are silly expensive?

So, in the "its about frelling time" department...

... Finally an electric flare that is USCG approved (and yes I know it looks like a man-overboard light).

The good news is from here on this is the only night signal you need to carry and combined with a distress flag as your day signal (which comes with the Sirius flare) its all you need to be 100% street legal with the USCG and other powers that be.

But wait... It gets better!

The Sirius electric flare is not "dated" with an expiry date which means the only thing you need to replace is the c-cell batteries when needful. That said, if you lose or screw it up you can order a replacement and get it shipped to you by the US Mail or something similar.

Of course I saved the best for last... It only costs $99!

Doing the happy dance...

Listening to Chuck Johnson

So it goes...

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Comment regarding Photos of a good flat bottomed skiff

Graham has written with a comment about leeboards: -

Nice pics. My life seems to be one long series of overdue jobs, so I know what a relief it is to be back on task!

The external chine logs I dont mind so much, but the leeboard?? I know there are some really good practical reasons for going down that path, and I know that Phil Bolger was a great advocate of them, but they take some getting used to.

Apart from the increased internal space, do you think you could just remind me what the benefits of a leeboard are; especially when used in conjunction with a flat bottomed hull like this one.

Well, Im not an expert on the subjuect, but the most obvious advantage of leeboards is exactly what Graham has pointed out - less clutter inside the part of the boat in which people want to sit. Now, having a centreboard case in there with you is not necessarily a bad thing. Ive found a case to be a great way to brace ones feet; to bundle people away from each other when sleeping; and to use as a sort of improvised set of hiking straps by hooking the soles of your feet under the upper external framing of the case while hiking out.

Another advantage of leeboards is that they are providing lateral plane from the surface of the water down to their tips, rather than from the bottom of the centreboard case to the tip. The problem there is that I suspect that the "end plate" effect of the bottom of the hull over the centreboard more than makes up for the increased effective area of the leeboard.

But despite all of that (including arguements about better hull strength without a centreboard slot), there is one overwhelming practical advantage of leeboards for a cruising dinghy, and that is avoiding the plague of having sand and shell-grit pumped up into the centreboard slot while the boat is pulled onto the beach with wavelets surrounding her. That is the reason why my centreboard designs have a positive method of forcing the centreboard down, rather than just relying on a block of ballasting lead in the board - a jambed board is a potentially serious problem, particularly when leaving a lee shore - you must be able to get the board down quickly, and the combination of sand and shel-grit inside a case is a serious problem. It is also a very good arguement in favour of a dagger board rather than a pivoting centreboard.

Ive been having an interesting discussion with a fellow in Maine about the effectivness of long, shallow keels. He sails a Phil Bolger Oldshoe and I occasionally sail a Bolger Micro - both of which have long, shallow keels. Both of us have been pleasantly surprised by just how effective these keels are - despite what the theorists will tell you. If you get the chance, read Arthur Ramsomes books in the Swallows and Amazons series (I read my first one at about eight years of age, and Im still reading the twelve-book series on a regular basis - they are that good), where he describes Swallow, a 14 ft clinker sailing dinghy with a shallow keel.

Here is me sailing along happily in my leeboard-equipped Bolger Nymph. The boat is on a run, with the boards raised, but I can assure you that they worked very well indeed!

This jpg shows my Whimbrel design (17ft x 6ft 9in), which incorporates leeboards for many of the above reasons. These plans are quite detailed, and although close to being finished, will still be a month or so. Too much work on my plate, and only one person to do the jobs!

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How good are small boats

My three sons (one of whom built his first boat at thirteen, and a lapstrake sailing dinghy at age fourteen) seem to have picked up one of my bad characteristics - that is, having too many interests.

The boatbuilding boy is obsessed with sailing, model aircraft, engines, quality cars, and full-sized gliding. He recently confided in me that he had plenty of other potential hobbies, but time and space have already become critical. Welcome to life, I say!

Recently he and I went for a really good day of sailing in his recently-acquired-but-very-old Jack Holt-designed Lazy E (a.k.a. National E). We experienced 20 to 25 knot conditions, and had to work very hard indeed to keep the old boat on her feet. But what a ride we had! Lots of trapeze work, and lots of planing. At one stage as we were planing on a reach, my boy yelled from the tiller that if Green Island hadnt been in the way, we would have had to keep going to New Zealand, because it was too much fun to change tacks.

This reminded me once again just how much satisfaction you can get from sailing dinghies (dinghys? - I dont know how to spell it...). The interesting thing was that when I questioned this young man about which activity he would keep doing, if only one was allowed, he was emphatic in saying it would have to be sailing. This is despite the obvious attraction of the aviation and mechanical interests.

I have a theory that the human brain stores away the sounds, and sights of a days sailing, and that the beneficial effects last for weeks or months. It doesnt take much to keep me going, although more is always better.

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Good Intent

Good Intent is a Bawley, another traditional craft from the English east coast.

Typically used to catch whitebait and shrimps in the Thames Estuary the Bawley is characterised by full, but relatively shallow hull lines and a transom stern very similar to that of a Thames barge in shape, giving the Bawley good sail carrying ability. The rig is typically a lose footed main with an almost vertical leech and a large topsail for catching the light airs as they made their way up the Thames.



Good Intent was lying at Woodbridge at the top of the River Deben in Suffolk a few years ago when these photographs were taken, even laid up at the quay she looked lovely.



Built in 1860 by Shrubsills of Milton at 36 feet on deck, she is registered as a Lowestoft boat - No. LO136, she fished for sprats and cod under sail until she retired from fishing in 1927.

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Good news bad news

L,G, & M with a bit of RCN Dazzle, a comic strip worth reading, and about the bad side of desalination watermaking...

Some bad news regarding our French friend Yann and SKROWL.

The good news is that Yann is OK and already thinking of the next boat...

Listening to Giant Panda Guerilla Dub Squad

So it goes...

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