From www.starclass.org Technical Articles This article was written for the September 2009 edition of Seahorse International Sailing magazine.
What had kept many builders from going in the direction of the ‘minimum rocker’ hull, as it was called, was the perception that the ‘standard’ shape was still considered the best all purpose design, whereas the boats with less rocker only excelled in the higher wind range – upwind and down. Conversely, the rounder, lower wetted surface shapes, were considered light weather standouts. Eventually, though, as sails and sailing technique started improving into the 1950s, all boats were soon being built to variations of the faster minimum rocker design. The next innovation, we’ll call it the ‘Vee’ bottom, took the principle of less rocker to another level. Even though the specifications called for the athwartships shape to be a segment of a true arc of a circle, there were several boats built that didn’t meet that standard. For better or worse, the class responded by creating minimum and maximum radii templates with relatively short chord lengths for stations 3, 6, 8 and 10. The result of this was that most competitive Stars being built today are of the maximum radii (ie as flat as possible) through the middle portion of the hull bottom. This has the secondary effect of creating an even flatter fore and aft shape. While all this was going on, the ‘wide bow’ made its debut appearance. None of us building boats in our basements or garages could understand how boats from an east coast builder were showing up on the racecourse with a plumb bow look. Well, surprise of surprises, in 1956 to be exact, the measurement tolerances were modified to greatly expand the maximum half-breath tolerance of the chine at station 1 from 57mm to 95mm – legalising the manipulation needed to produce a plumb stem. Quite a change, but it at least leveled the playing field going forwards. Several boats in our own 6th District, which includes Washington State and British Columbia, as an example, were successfully modified shortly after to take advantage of this new measurement. For a few years after that, everything seemed to be running smoothly... except that it was obvious that with the arrival of fiberglass we would soon need – among other things – a class minimum weight. Even though there were cedar boats rumoured to be as light as 610kg, the only restrictions up until then being the scantlings, the class decided on 671kg as a good lower weight. This has proven a good figure, but from then until today the class continues to try to resolve the next issue of controlling the weight distribution and the lay-up of the hull. There have been attempts to control the situation (the rules specify an ‘even’ weight distribution) but to date the class has not come up with a workable solution and wide differences continue to exist.
So that is how it went, and it’s been good. Even though aluminum masts do fail, they are much more reliable than were their elegant but fragile predecessors. More recently, there has been discussion of carbon fibre spars; from my limited experience I would say that the technology isn’t there as of this date – maybe in the future that will change. The way Star sailors get all worked up over the differences in the bend characteristics of aluminum spars from the same mast builder, I can’t imagine what would be the uproar we’d have with carbon... From the mid-seventies up through the mid-eighties Star hull design generally remained pretty stable, other than adding several measurement points to the rudder and keel, but those of us on the class technical committee could see the potential for trouble on the horizon. The fact that the measurement tolerances were still so large coupled with serious designers taking a look at the potential for breakthrough shapes, made it obvious that we needed to develop a new set of Star plans based on the designs that were currently being utilized but with much, much tighter limits. That work was completed in a relatively short period of time with a lot of help from Hannes Gubler, who created the new lines drawing, as well as Andy Menkart and several others. In other words, the Star as it appears on the plans being issued today isn’t the same as what was being sent out to builders for the prior 70 plus years. Our objective was multi purposed, to tighten the Statute of Limitations around a modern hull shape, so that it would be virtually impossible to build a legal, non-competitive boat and to add some measurements where, believe it or not, there weren’t any before. At the same time, we compared our new envelope with the other, competitive boats being built to make sure that they would all conform. Even though there has been some criticism of the fact that the sheer heights at the extreme ends of the boat weren’t addressed, I would say that what we did has proven good for the class. New ‘breakthrough’ boats come and go, but today there is a healthy selection of excellent boatbuilders able to turn out a series-built championship winning Star boat design... off-the-shelf. ------------ Bill Buchan was also a Star builder, and built the ‘Long Beach’ special that took him and Steve Erickson to the 1984 Olympic gold medal. Bill’s son Carl also won the 1992 world title with Hugo Schreiner. He was talking to class historian David Bolles and 1986 Star World Champion Vince Brun. © Copyright 2007 by starclass.org |