Return to my home schooling page100 Small Boat Rigs
by Phillip C. Bolger. 261 pages.Where to find it:
Not in the public domain, so no freebies.No longer in print. Buy used from Amazon.com
The later edition is available from Instant Boats
100 Small Boat Rigs Reviewed
If you are interested in sailing, you need this book. Bolger is one of the most experienced and unconventional naval architects today, and he's very familiar with the history of sailing craft. He has experimented with old-fashioned rigs and with new-fangled rigs, and in this book, he tells us where they're appropriate and how to make them work. It may well be that your purpose is not best served by today's ``standard rig''. If so, you can find something better for you in here.
Table of Contents
The Latest Edition
The latest edition adds three rigs, bringing the title up to 103 Small Boat Rigs. The most significant addition, for me, is Bolger's Chinese Gaff rig, a hybrid between the junk sail (a fully-battened balanced lug) and the traditional gaff sail. Unless you're specifically interested in that, you can probably be satisfied with either edition.The Introduction
The first chapter is Introduction: Crude Aerodynamics. Bolger begins by explaining how a boat can blow downwind, and why a sailboat going downwind will tend to roll. He then explains how the sail can make the boat go across, or into the wind. He explains the flow of the air over the sail, and discusses separately the airflow over the two sides of sail. There is more to sailing than lift and the Bernoulli effect. Bolger tells us that the windward side of the sail deflects air backwards, causing an equal and opposite reaction which pushes the boat forward. The other side of the sail, meanwhile, can (if it's correctly adjusted) develop a low pressure (lift) which will add to the sail's pull. He helps us to understand how the sails drive the boat by telling us to look at the forces transmitted to the hull: to look at the sheets. Even if you don't intuitively grasp the aerodynamics of the sail, you can see the forces acting on the hull, just by looking at the straining sheets.He devotes several paragraphs to the differences between aircraft wings and sails, and tells us how those differences call for different shapes. Aircraft use wings with thick leading edges, which reduce the likelihood of stall, but increase drag. Sailboats can always keep their sails at the optimal angle of attack, so they can have a thinner leading edge and less drag.
Perhaps the most important portion of the introduction is his discussion of efficiency. He begins by saying: ``If a large sail can be designed that is cheap, easy to handle, and has little heeling effect, it is more efficient than a small sail that's expensive, hard to handle, with large heeling effect, even if they have the same power to drive the boat.'' As he points out, fashion and complex racing rules can obscure that basic truth. The existance of those large, cheap sails is what makes this book important to folks who don't care about fashion and racing rules.
He doesn't go deeply into his subject, he studiously avoids all mention of math, and he leaves out a lot of interesting topics, like why it is that airplanes can fly upside down. He has also ommitted all mention of hydrodynamics, so there is no mention of the similarities and differences between keels and wings, or of why one might choose a particular shape for a keel or fin. Still, this book is about rigs, not daggerboards. Bolger promised a crude introduction, and he delivers a very good one in barely five pages. Einstein is supposed to have said that the true test of understanding is the ability to explain your subject to a child. By that measure, Bolger clearly understands aerodynamics.
The Rigs
The rigs begin with 27 cat rigs: one mast, one sail. There isn't quite as much variety here as the sheer number suggests, because often they're in pairs: one with a boom, one without. Bolger is trying to be exhaustive here, because these are the building-blocks for the more complex rigs he'll cover later. These simple rigs are where Bolger introduces the various ways of shaping and rigging a sail, and tells us about their characteristics. With no other masts or sails to muddy our view, he can tell us what their strong and weak points are, and what they might (or might not) be suitable for. When he presents multi-mast, multi-sail rigs later, he assumes that you've read about those sails in Part 1.
In the section on cat ketches, he presents a miniature Zulu lugger (rig 55). The Zulus were Scottish fishing boats with lug rigs. This looks like the perfect rig for a simple motorsailer which could sail and motor reasonably well, without an expensive rig. In the section on ketches, he covers the wishbone ketch (rig 82). This is an amazingly complicated rig, and Bolger explains how it can be made to work, and why some few boats use it. In the section on cat schooners, he covers some interesting rigs, but misses the three-masted cat schooner with fore and main masts junk rigged and the mizzen a jib-headed sprit sail. This is a rig I've seen here in Juneau on a big sharpie, and it looks very practical.
Summary
This book's strength is its breadth. Unavoidably, covering 100 rigs in just 261 pages means that none of them are covered in much depth. They each get about two pages, with part of those two pages taken by a Bolger cartoon which is easily worth 1000 words of explanation. John Leather's book ``Gaff Rig'' or van Loan and Haggerty's ``The Chinese Sailing Rig'' show how much detail is needed to cover any one of these rigs thoroughly. This book is a fascinating catalog of suggestions, but you will have to follow up your favorites elsewhere.
I'm not sure how Bolger chose the rigs he included here, but I suspect that he picked them because he has some personal knowlege of them. Some of these, like the modernistic staysail cat (rig 10) were pioneered by Bolger's friends or mentors and some like the dipping lug (rig 15) are traditional favorites in some part of the world. In his preface, Bolger warns that much of what he writes is his opinion or his conjecture. It's probably safe to assume that where he talks about his personal experience with a rig, you're getting the straight story, and that when he introduces a rig as ``hypothetical'' (the ``kite sail'' rig 97), you should let someone else try it first. Most of the rigs, of course, are traditional and Bolger has enough personal experience at sailing and using them, or some variant of them, that he can speak authoritatively on their strengths and weaknesses.