by Derek Van Loan suffers from an identity crisis. It appears to be known primarily by its subtitle, and on the front cover, the subtitle is far more prominent than the main title (and on the spine, the main title doesnt appear at all). In fact, "Design and Build Your Own Junk Rig" is a more accurate title than "The Chinese Sailing Rig," but even then, its a stretch, which Ill get to.Van Loan says virtually nothing about the Chinese sailing rig -- nothing about its history, nothing about its current usage, next to nothing about how to sail it and, most seriously, nothing whatsoever about its pros and cons compared to Western rigs like the Marconi, gaff, etc. He seems to assume that the reader is already persuaded about the superiority of the junk rig and is ready to retrofit an existing non-junk-rigged boat with one -- and that he or she only needs to know how.
Which gets me to the promised criticism of the subtitle. Van Loan gives very little advice about how to design a junk rig, per se. Instead, he tells you how to spec a junk rig following his favorite design. Van Loan evidently has a good amount of experience playing around with the rig, and hes found a formula that works for him...and for the type of boat he likes, and the type of sailing he does, in the location where he uses it. And he expects the reader to follow his system, even if the readers needs may differ. So he gives guidelines without explanation, such as this:
The number of battens is dependent on the sail area. Up to 200 square feet, four or five battens will suffice. Use five or six battens on a sail where the area is from 200 to 700 square feet.
As to why you should use fewer or more battens, he gives no explanation. Following his guidelines, one could use anywhere from four to six battens for a 200 square foot sail, but Van Loan doesnt give any help in deciding what is the right number within a range that contains a full 50 percent spread.
One suspects that the reason for this is that the authors understanding is entirely experiential, and that he is lacking is theoretical knowledge. His instructions for finding the center of lateral resistance consist of making a cardboard cutout of a profile of the boats underbody and balancing it on a pin (perhaps he doesnt know how to do the math?), with this caveat:
If the rudder of the vessel is large or if the vessel has a fin keel, daggerboard, or centerboard, include about one-third its area, from its leading edge, in your underwater profile
Oh great: "about one third". Perhaps if he had explained in the first place how to calculate area, we might be able to make a start. But even so, how precise do we need to be to meet his "about" one-third guideline? Is 30% too little? How about 25%? Dont bother looking, for theres no help to be found.
By eliminating theory and math, Van Loan has attempted to make things as simple as possible, but therein lies the problem: he gives the reader not enough information upon which to make informed decisions. And then he compounds the problem by assuming specialized knowledge that the reader is unlikely to have, especially sailmakers and riggers terminology. The glossary is only occasionally helpful, consisting mainly of the better-known terms, and ignoring some of the more obscure ones.
Van Loans line drawings are clear and good, and his prose is generally easy to follow. If one were to follow the books recommendations, one would probably end up with a workable -- maybe even a very good -- rig. But that rig would be based more or less blindly on someone elses preferences, and the DIYer would have little understanding of why it works the way it does, or how it might be improved.
"Design and Build Your Own Junk Rig" is full of editing errors, lacking in theory, and inadequate in its discussion of the authors particular preferences. For a book in its third edition, its a notably weak effort.
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