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Split LeadSSB AntennaM No needfor backstayinsulatorsM Easy installationM No swaging, nocuttingM Tough, waterproof,reusableM Highly conductiveRF elementsM Watertight leadwireto antennaconnectionM Stiff 34’ LDPEhousing securesfirmly to backstaywireGAM Electronics, Inc.191 Varney StreetManchester, NH 03102Phone: (603) 627-1010Fax: (603) 622-4738N Mwww.gamelectronicsinc.comgamelectronicsinc@juno.comCommunicationsexpert Gordon Westreports“I have donenumerous SSB hamand marine radiochecks with this systemand have foundno discernible signallosses, even whenused with a wellgroundedbackstayaboard a steelhulledvessel. Theantenna...can bangout a signal just asthough it were suspendedin mid-air.”– Sail MagazineOctober 2005POWER VOYAGINGoptionally — left open and not weldedtogether at the trailing edge. Theseare precurved about as you see in thedrawing; however, you can adjustthem by grabbing them with Vise-Grip pliers, or whatever, and bendingthem in or out, either evenly fromtop to bottom, or to varying degreesfrom top to bottom and differentlyport and starboard. The rather cleveradvantage of this is that you canadjust the flare-out on each side bytrial and error until your boat’s handlingis exactly predictable and exactlyas you want it. Having worked onthe design of several boats fitted withthe MacLear Thistle rudder, I canattest that it works as advertised.The drawing shows the sectionproportions (along with theoptional endplates). Note that —as the center of pressure is a bit furtheraft on the Thistle rudder —the rudder stock is at 20 percentchord, giving 20 percent balance.Trying the Thistle rudderOn larger vessels the entire rudder isusually fabricated from aluminum orsteel. For smaller vessels, you canmake the forward three-quarters toseven-eights of the rudder blade inthe usual way, with a stainless steel orbronze stock through a wood/fiberglassblade. Add the flared-out trailingedges of simply curved aluminumplate, let in flush to the body of therudder blade. You can retrofit almostany standard rudder installation thisway. Even at the normal range (35degrees hard-over-to-hard-over) steeringis more precise and predictable.The only improvement I’ve made tothe MacLear Thistle rudder is —where possible — to build on endplates over the top and bottom of theentire rudder. These are fastened tothe body of the rudder blade, butproject aft over the curved flaredends, either attached or unattached.In this way you still have the endplateeffect at the trailing edge, whileretaining adjustability. Such endplatesfurther improve the MacLear Thistlerudder’s excellent helm response.Thistle-rudder steeringA rudder like this gives unusuallypositive steering, and my office hasinstalled them on most of our singlescrewdisplacement cruisers. Thoughyou can turn the MacLear Thistlerudder over to 40 degrees, all theinstallations I’ve done have only goneto the normal 35 degrees. At speed,somewhat less rudder angle is neededto get the same course correctionyou’d achieve with a standard rudder.During low-speed maneuvering,these rudders really shine. Steeringresponse is both crisp and predictable.You can very quickly kickthe stern of your boat around toexactly where you want it.Here’s what the skipper of one ofmy designs, Imagine, had to sayabout the boat’s handling with theThistle rudder:“Imagine is doing wonderfully! Todate, my strongest impression is howeasily she handles in close quarters.We’ve been staying at quaint, butsmall, marinas that are quite challengingfor even a twin screw to maneuverin. Two nights ago I was evenforced to dock stern-to. I gave theharbormaster my length and he askedfor my beam. I replied, ‘14 feet 6inches,’ and he said, ‘Great. In thatcase, you can stay because I have one16 OCEAN NAVIGATOR SEPTEMBER 2010 www.oceannavigator.com