
|
General Concepts- Since commencing production in November 1994, David Lambourne Spars and Yacht Rigging has constantly strived to produce high quality masts and rigging with no compromise .All facets of the product from design to assembly and installation are undertaken with the same attitude to producing the highest quality product available.Some aspects of this attitude are quite subtle and to this end , we are pleased to detail some of the more important features for your general information and confidence.
|

|
Mast Extrusion Profiles The first building blocks are the actual extrusions. The range of dies we have are the most modern and complete set of matched sections available. Ideally suited to multihulls and 1,2,3 or 4 panel rigs. The moments of inertia are ideally suited to modern designs which require higher athwartships stiffness. The wider back section provides stronger attachment of fittings such as goosenecks and spreaders . We also have extruded doubler plates for increased attachment strength and to add stiffness where needed. Slide in tracks to suit most popular brands of batten systems , ensures the strongest possible connection.
|
Fractional head fittingCAD profile cut from special custom extrusion , the head features machined Ertalyte wide sheaves to eliminate halyard chafe , with substantial axle pins for reliability. Boom topping lift sheaves are also fitted . All heads are welded in for maximum strength.

|
Precamber SideTaper The side taper we use enables us to remove the optimum amount of material and the special technique induces a constant bend through the hounds. This ensures the mainsail has no need for variation in luff curve ensuring optimum sail shape at full hoist as well as 1st secd and third reef positions.
|

|
Self Aligning Tangs Absolutely unique in the world, these tangs provide the best method of shroud attachment available . Positive connection providing perfect alignment at all times, these tangs have been tested to well above the breaking strain of the wire. Mast wall doubler plates ensure there is absolutely no doubt about these fittings….ever !! (and isnt that how it should always be ?)
|

|
Forestay Lug The most highly stressed stay attachment requires absolute no-compromise design. Heavy internal sleeve welded to a plate alloy lug which is then mechanicaly fastened to eliminate any fatigue. The component is anodised to eliminate corrosion and secured using antocorrosive paste. The stay bearing surface is stainless bushed to eliminate wear and ensure serviceability
|

|
Diamonds and Jumpers To achieve the strongest attachment of diamond arms, we utilise the forward and aft corner of the profile. This spread of the base ensures the best control of twist and bend without weakening the profile.Cast Stainless steel bases with hdp gaskets to eliminate corrosion , provide unquestioned strength. High strength tube arms with machined end plates are black anodised for apearance and corrosion resistance. Upper diamonds have clamp tips machined from high grade plate (not cast) and the lower tips are milled from the same material for maximum strength and reliability. Alloy castings in this high load area are prone to fatigue and corrosion. Bracing tubes protect lights, electrics , halyards and sails.
|

|
Halyard entry boxes for Jib, Spinnaker and Screecher Rounded extrusion profiles are fully welded to provide the strongest and most reliable halyard entry system. With the use of High Modulus fibre halyards we have found that mechanicaly fastened sheave boxes fail . High strength sheaves and generous sized axle pins assure the owner of years of trouble free service.
|

|
Gooseneck High contact area for strong attachment and a generous number of fasteners, liberally coated with anticorrosive , ensures this fitting is there to last the distance. Stainless steel tack bolt and cast stainless knuckle fitted with nylon spacers provides years of trouble free service. The boom lug is also stainless steel bushed to eliminate wear at the boom connection.
|

|
Mast base and Jacking Structure. Due to the size of the turnbuckles required in larger rigging, it is impractical to even attempt to tension such a rig using the adjusters. Hence the jacking system is fitted standard to such boats as the Perry 57 Catamaran. The tension can be easily released for adjustment or service. This significantly increases the life of turnbuckles and enables proper rig tension.
Halyard turn blocks Cast in High strength Stainless , these provide accurate and strong lead of lines aft to the cockpit. Extra brackets allow for additional lines if required.
|

|
Booms Larger cat booms The Perry 57 Cat boom features specially positioned sheave boxes for the 3rd reef which is single line as are the first two reefs. All the internal reef blocks feature large diameter low friction sheaves. The outboard sheaves are 120mm diameter on a large axle to ensure easy reliable reefing.Inboard sheaves are mounted on high load stainless brackets. External reinforcing is provided to support the mid boom sheeting. High load outhaul track is supplied to carry the extreme clew load of the sail. A specially designed frame to carry the boom cover includes integral tracks for the cover and awnings .
One of the simplest features on all our booms is the end cover plate. This allows easy access for maintenance and prevents birds from nesting inside the boom.
|
Metal finishes- Painting and Anodising Clear anodising after production provides the best protection for Aluminium masts. Average 20microns of coating gives up to 20 yrs of good protection. Quality Urethane linear paint finish is an option- Prior to painting, the mast and boom are sanded , acid washed & chemically etched. We then apply 3 coats of epoxy undercoat and 3 coats of 2 pack urethane gloss. Every care is taken in the final assembly , to minimize any corrosion. Insulating washers are used under stainless parts and jointing compound on all fastenings. Black anodising on all smaller components provides excellent protection as well as a smart contrasting appearance.
 Electrics All electrics are run in conduits which are attached to the inside mast wall. For ease and protection the conduits are lead in such a way as to allow the wiring to exit directly into the light fitings etc. Extra large conduits are supplied for Radar cables to make installation of the scanner as easy as possible. Electrical connections are always vulnerable in a marine environment and hence serviceability is a very high priority .
|
|
|