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Saga 43 - Hull #39

Construction

The hull of the Saga 43 has a nearly plumb bow and rakish stern with a convenient walk-out swim platform. Construction of the hull is of hand-laid fiberglass, using premium grade polyester resin, with two layers of Vinylester resin for added osmotic protection. There is aircraft grade Baltek balsa coring in the hull and deck; the core is voided or replaced with high density backing plates in areas of thru-hulls or deck hardware attachment. Along the keel is additional heavy duty keel solid laminate layup for additional keel and mast support strength. The aluminum slotted toe rail has a PVC rub rail for full length hull side protection. The keel is externally hung lead with a double row of 10 1” keel bolts. All bulkheads and furniture components are fully bonded to the hull and deck. The hull to deck joint is thru-bolted on 4” centers and bonded with polyurethane adhesive sealant. There is a massive sub floor framing structure utilizing bi-directional E-Glass reinforcements for hull stiffness and added strength. The exterior is tropics friendly, with no exterior teak to maintain. The cockpit seats have nice high coamings for great back support and are 7’6” long, making them wonderful for cockpit sleeping. Foot braces are molded into the cockpit sole for the helm and crew.

Hull

The hull of the SAGA 43 is a one-piece fiberglass sandwich moulding utilizing an end-grain balsa core to achieve stiffness and light weight in the composite lamination. The exterior finish is a premium grade ISO-NPG polyester gelcoat that has been sprayed into the highly polished hull mold. Two laminate layers, using vinylester resin for increased resistance to osmotic blistering, are applied to the inside of the gelcoat. Additional layers, using biaxial fiberglass cloth are then laminated into the hull mold. The balsa core material is sandwiched between these inner layers and outer laminate skins. This multi-layer building technique adds strength and stiffness properties to the hull while ensuring that overall weight is kept to a minimum. The end-grain balsa core material is removed in areas where through-hulls or fittings are to be installed; this eliminates any potential of water incursion into the core material. Areas that may be subjected to increased stress have additional laminates for greater strength. Polyester resins are utilised in the remainder of the laminations following the vinylester layers.

Deck

The deck and cockpit are formed by a single fiberglass moulding with a gelcoated surface. End-grain balsa core is incorporated into the structure for stiffness. Core material has been removed in all areas where hardware and deck fittings are located to eliminate the potential of water incursion into the core material. For high stress fittings, aluminum plate is incorporated into the laminate for additional strength. The contrasting non-skid finish is moulded into the deck. Before drilling holes in the deck, cabin house or cockpit, consult the deck laminate drawing in this manual. (Sec. 11 Drawings)

Hull-Deck Joint

The hull-deck joint is secured both mechanically and chemically. The hull’s moulded flange is coated with a high-tenacity, polyurethane marine adhesive sealant; the deck is then placed on the hull flange and fastened through the extruded aluminum toe rail to the hull by stainless steel bolts every 4 inches.

The adhesive sealant used in the hull-deck joint fulfills two extremely important requirements.

  1. Prevention of leaks in the hull-deck joint as it undergoes the stresses of sailing, owing to the flexibility of the sealant.
  2. Increased strength for the hull-deck joint due to the adhesive nature of the sealant.

If the SS fasteners should ever need maintenance or in the event of damage in the gunwale area, we take particular care to make the fasteners accessible with removable interior panels wherever possible. The external vinyl rubrail, which provides important topsides and gunwale collision protection, is inserted into a channel in the aluminum toe rail. Should the vinyl rubrail ever need replacing, it can be readily accomplished, by the owner, without disturbing the hull-deck seal.

Rudder & Steering

The rudder is constructed of two moulded composite shells filled with a low density fiberglass compound to prevent water incursion and damage. The two halves are bonded together around the 4” dia. stainless steel rudder post. Stainless steel plates are welded to the rudder post to provide additional strength and stiffness in the rudder blade.

The rudder may be removed by loosening the retaining collar and steering quadrant, which are found under the cockpit. The rudder must be supported from below during this procedure, then lowered carefully. This is normally carried out with the boat hauled out of the water but may be accomplished with the boat afloat. The rudder post passes through the hull with a close tolerance fit between the shaft and the waterproof bearings.

EDSON RADIAL DRIVE® wheel steering is installed on some SAGA 43s, others have Whitlock COBRA steering. The steering wheel is on a tapered shaft secured by a large nut and a keyway in both cases. Inside the pedestal, on the shaft, is a gear; this is the case for both types of steering. In the EDSON, a heavy-duty SS chain passes over the gear, to each end of the chain a cable is attached. The two cables are linked to the radial drive quadrant which is clamped around the rudder post. EDSON has provided maintenance instructions concerning the steering system.

The Whitlock COBRA steering system uses a quadrant gear to drive a SS tube in the pedestal, this connects to another SS tube in the lazarette that transmits motion to a steering arm attached to the rudder post.

Excellent access to the steering system is afforded through the cockpit sail locker.

Ballast

The keel is an external, lead ballast type. The lead is alloyed with antimony for added strength and hardness. It is cast in one piece to Robert Perry’s design. Beyond providing stability for the yacht, the sophisticated foil shape of the keel produces hydrodynamic lift while sailing to windward, reducing leeway angle and enhancing upwind performance. The keel is shaped to minimise drag, maximise lift, and carries a substantial bulb at its tip to increase stability without excessive ballast weight. Shoal draft keels have a larger bulb and additional ballast to provide a righting moment similar to the deep draft version.

The keel is fastened to a heavily reinforced hull sump by means of stainless steel bolts which are cast into the lead. These bolts project through the keel sump and are bedded with sealing material to prevent water leaks. The bolts are secured by large stainless steel nuts and backing plates that are accessible in the bilge beneath the saloon sole. The deep keel sump significantly lowers the centre of gravity of the ballast weight while providing a collection point for bilge water. (Without a deep sump, bilge water can run up into lockers when the boat heels.)

A 856lb keel shoe was added in 2004. Manufactured by the Mars Metal Company in Burlington, Ontario, Canada.

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