CD03 - Issue #74: Designer / Builder Paul Bieker--Process Control ...

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map looks uneven, with really bigspikes surrounded by areas of lowerpressure. It's a statistical thing: the biggerthe panel you're looking at, the lesslikely it is that loads will exceed a largeaverage pressure. But in large monocoquestructures, local pressures can beexceedingly high. Panels support thosepressures by bending. I think basicengineering would have told you in alot of cases that you'd get core-shearproblems." Since Bieker prefers to splithis 14 hulls into small supported panels,FEA is ideally suited to helping himengineer his elegant spiderweb framingset at oblique angles to the centerline,while CAD allows him to provide accuratetemplates so that even this complexframing simply "egg crates" together.I" guess I view myself as someone whotries to apply good engineering toaccomplish things that might otherwisenot have been done," Bieker says. "I seeboats as very much related to airplanes,particularly the relationships betweendrag and weight. Not that I'm JoeUltralight, you understand. But if there'sa lot of weight without purpose, itmight as well be put in ballast orremoved for reduced displacement."Light displacement is part of Bieker'sstyle, but his engineering expertise andhands-on boatbuilding experience alsoallow him to mate the theoreticallysuperior with the pragmatically doable.Increasingly, Bieker isapplying his style, whichhas served large commercialvessels andInternational 14s equallywell, to mid-sized watercraft.Bieker's first keelboatcommission was for a55' (16.7m) skinny sloopwith a notably angularsuperstructure, a straightsheer, and a near-plumbstem with boxy probiscus.Bieker recalls, "OneSeattle yacht designertold me that 'It has anose like a dogfishshark.' Some peoplethink it's a cool-lookingboat because it's quitelow in the water andangular. I admit the styling may be overthe top. I don't try to make a boat ugly;I do try to make it purposeful withoutfeatures that lack a reason for being. Inthis case, the client wanted the biggestboat that could be driven by a sail planhe could handle with his wife and twoA computer rendering, (using Rhino software) of theRip Tide 55, a fast cruiser. Topsides, deck, superstructure,and much of the interior are built with flatcomposite panels. The mast steps on a robust podmounted atop the cabin. This boat's cost-effectiveconstruction system was documented in PBB No. 45.DECEMBER/JANUARY 2002 77
kids. He also wanted an aggressivelystyled boat."Freed from traditional constraints forthat commission, Bieker mated a smallishsail plan to an easily driven, narrow,balanced hull with deep T-bulb andminimal keel area optimized by a trimtab when set at 5° to 7°. Twin rudderstoe out at about 15°. The carbonskinned,Nomex-cored flat panels thatcomprise the deck and coachroof andcreate the boat's angular aesthetic werebuilt efficiently on flat layup tables toeliminate molds. Even the boxy noseprovides a very stiff bowsprit andanchor roller that keeps a hanging hookfrom scarring the topsides. [For more onthe 55 in particular and its type of constructionin general, see PBB No. 45."Boatbuilding with Flat CompositePanels"—Ed]Bieker borrowed a page from Openclassraceboats and placed the boomgooseneck on a deck-mounted pod,thereby eliminating shear loads from theboom on the mast section, a commonpoint of failure. With the gooseneck aft,the mainsail foot and leech automaticallyloosen when the sail is eased. TheThe similarity in basic shape between Bieker's small boats and his larger ones canbe clearly seen in perspective drawings of a 55 (left) and a B-3 International 14(right). These are chine boats, but the transition is subtle and the bottoms are round.pod appears stolen from an armoredvehicle, but integrates numerous functions.Winches centralize halyard handlingfor shorthanded sailing. The 55'shydraulic ram perfectly tensions the rigbut can be eased alter the crew fixesthe position with a ring nut. Internalstructural baffles reinforce the cabinedge against diagonal rigging loads andcreate a giant ventilator for the headbelow without protruding Dorade vents.The ventilator also creates a miniature"cathedral ceiling" over the WC, wheresomeone sitting might wonder when themast above, driven by 50,000 lbs(22,679.6 kg) of compression, is goingto take a core sample. But the pod'ssides actually cany the loads directly tothe main bulkhead and to two longitudinalbulkheads flanking the head.The mast section (fabricated by GMTin Bristol, Rhode Island) is round, as onmany 14s. "Elongated mast sections,"says Bieker, "make sense when in-linespreaders lend no real fore-and-aft supportbetween the masthead and deck orsplit lower shrouds. With swept-backspreaders, though, the rig is locked78 PROFESSIONAL BOATBUILDER
Page 1 and 2: The Following ArticleIs ProvidedCou
Page 3 and 4: Bieker's BoatsForm flows from funct
Page 5: Paul Bieker preps his own Internati
Page 8 and 9: An isometric view of alifting hydro
Page 10 and 11: are plates maintaining the strength
Page 14 and 15: almost as well fore-and-aft as it i
Page 16 and 17: Bieker took a retired racing sailbo
Page 18 and 19: Resin emerges through the peel ply,

CD03 - Issue #74: Designer / Builder Paul Bieker--Process Control ...

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