Plansfor The New Goldfield in the Making
By H.E. Ross
Cayman Maritime Heritage Foundation
Ron Moore, the creator of the Moore 24,and steadfast member of the fast is-fun boat designer cult outSanta Cruz, California, responded to a line drawing of the Goldfield,stating emphatically that this design could see 20+ knots easilyin exotic materials.
Mr. Moore also included that it would bea culmination of his career to develop a design for the CaymanMaritime Heritage Foundation replication plans. He rattled offa list of composite compositions that sounded like a cross between,computer contractions and bio-tech formulas to comprise a monococquestructure, meaning a seamless hull and deck.
When asked what price for a cold mouldedhull and deck with built-in bulkheads, Ron Moore acted a littlecondescending that such an old construction technique would evenbe an add-on to his conversation about boat building in the 21stCentury.
When asked about plank-on-edge construction,he simply answered, why?
The exotics, he contested, could last longer,weigh much less, alleviate strain on the rigging, allow the weightto be put in the right places, would be much stronger and wouldbe efficiently much, much faster
The price haunted the conversation but couldonly be guessed at and the exotics were scaled back down to coldmoulding, or the West System veneer-epoxy layering technique.
For the purposes of this article I am goingto describe five options for the construction of a new Goldfield.Keeping in mind that the vessel will have to look almost identicalto the original yet is eligible for international passenger certificationas a cadet sailing school and as a marine research vessel.
The methods are the traditional plank onedge, strip planking, epoxy saturation veneer layering, steeland glass fibre techniques.
Plank On Edge
The traditional method of boat and shipconstruction has over six thousand years of history and of a recordedknowledge of development in its background. Fastening one plankof wood is the oldest form of shipbuilding.
In the real old days before iron they usedfibres to tie the planks together and did a lot of bailing. Later,nails and then screws, bolts and rivets were used to keep theplanks seated upon their frames, or timbers and still enough notto let a whole bunch of water enter the hull.
A flexible, water -repellent mixture wassqueezed between the edges of the planks as caulking. It had tobe flexible so that the wood would not crumble when moving throughthe seas. A traditionally built vessel relies upon its hull'splank movement contours to slip through the waters instead ofbeating through it.
Some of the assets that good traditionalboat design and construction have over the other are gracefulimperfection, heavy scantling toughness, climate insulation, quiteunder sail, ease of motion, accessibility for survey review, stabilityin foul weather, ease of repair, availability of wooden boat shipwrights,authenticity in replication and an aesthetic appeal.
Some of the detractions are the ever -presentthreat of fresh water rot, teredo worm destruction, electrolysiscorrosion, engine vibration disintegration, cramped interior,separation of hull and deck, maintenance caulking, protectivepaint coverings, difficulty in certification for charter and insurance,need for annual haul-out, scarcity of appropriate woods, distributionof weight and resultant loss of speed.
The Goldfield was built as a Cayman TurtleSchooner with a large hold for carrying turtle. She had a largeaft cabin for passenger travel, but the crew mainly slept on thedeck or wherever they could get protected space.
Her design has brilliantly fast under-waterlines, but her weight restrained a lot of her potential. She wasbuilt of heavy scantlings and was a strong, sturdy vessel ableto scrape a little coral every now and then with minor repairscorrecting a scratch, dent or break.
Her Cayman existence saw no engine in herhold or through hull fittings blemishing her under-body. A shipcould be duplicated and would look just like a Goldfield and,probably to a large degree, feel like the great turtle schoonerin her prime.
The difference is in the use of the vessel.If the vessel is to be utilised for sail training, then bunksbelow have to be fitted in the design which will take up quitea bit of space.
If the Goldfield is to be chartered a couple of cabins and somemethod of showering has to give a sense of privacy to the characters.Again, the problem is cramped quarters.
A plank on the edge vessel of Goldfield'sdimension, with her four-inch thick (frame covering) takes awayone foot of beam width, with four to six inches from the cabintop. A lot of space would be taken up with strengthening the integrityof the hull, deck and rigging at the sacrifice of room below.
On a new plank on edge Goldfield, two cabinscan be designed as guest quarters with a shared head or toiletarea. A small skipper's cabin could be fit in siding the enginecompartment.
Permanent bunk berthing in the old turtlehold could suffice for six to eight cadets with the permanentcrew of three living further forward near the foc'sle in an openbunk arrangement with curtains for privacy. The galley and diningarea would be elevated and airy but would have to be shared bythe characters, crew and cadets.
A modern navigation console station wouldcarry all the instruments that a modern long distance sailingvessel needs today, including computer, radio-telephone, singleside-band, transreceiver, radar, sonar, GPS, cellular telephone,intercom, auto-pilot, chronometer, barometer and compass.
The traditional plank on edge Cayman TopmastTurtle Schooner, Goldfield II, could cost upwards of US$800,000to construct.
Strip Planking
Strip planking is the easiest method ofvessel construction. A mould is set up and strips of soft wood,small 1/2" to1" wide planks are placed edge-to-edgeand bent to contour the mould. The actual planking is startedat the turn of the bilge and laid up to the keel and down to thesheer line. The planks are glued and fastened with dowels to theother planks until the hull is solid.
Retrievable screws hold down the plankingto the mould. The excess in the bow and stern is trimmed off alongtheir contours and the hull is almost finished. Pull out the mouldscrews and add a couple of epoxy saturated veneers over the stripplanking and you have a strong, firm, hull with bulkheads butvirtually no frames. The interior can show the wooden strips andthe vessel will definitely retain the felling of wood.
The best things about strip planking are the ease of construction,if epoxy coated there is no problem with worms or rot. The minimaldependency upon fasteners excludes a lot of the worry about electrolysis.
Insulation, noise reduction under sail,easy accessibility for survey review, no caulking, a tremendousimprovement on space below because of the lack of framing, aestheticcontrol in replication, control of weight distribution are verygood points for this method of construction.
The other side is the problem of reparationwith or without the veneer, a dependency upon the locations andbonding of bulkheads, lighter than traditional wood constructionbut heavier than the epoxy veneer layering method and the difficultyin bonding deck to hull.
A strip planked Goldfield II, with a fewlayers of epoxy saturated veneer would cost upwards from US$700,000.
Epoxy Saturation Veneer Layering Construction
Simply put, the epoxy saturation techniqueor cold moulding is the building up of thin strips of veneer orply saturated with marine epoxy resin glue, sandwich fashion,on a mould. The glue hardens bonding the ply to create a mouldedply wood structure. The veneer is rotated in cross layering patternsfor integral strength. Because of this rotating of the grainsin the ply very little structural framing is needed to strengthenthe form.
Though the cold moulding technique has beenaround since the 1930s the glues have not proven adequate forthe stresses and tension of work on the open seas.
In 1979 the Gougeon Brothers of Bay City Michigan published abook on the merits of a wood/epoxy resin composite construction,which they trademarked as the west (West Epoxy Saturation Technique)System.
Since that publication and the emphasisswitch to lightness in hull design combined with the phenomenalupswing in interest in classic boat building and restoration,epoxy saturation took off as the best method of building a vesselto last.
Also the marketing point was made that epoxysaturated vessels needed less maintenance time than traditionallybuilt or glass fibre built vessels.
The assets of epoxy saturation techniqueconstruction are ease of construction, detailed replication possibilities,control of the distribution of weight, hull and deck continuity,bonded bulkhead strength, distribution of hull and corner thicknessthroughout vessels, ease of reinforcing points, allow-ance formore room below because of lack of scantling bulkiness, watertightconstruction, rooms built in as strengthening partitions, accessibilityfor survey review, no possibility for rot or ship worm destruction,insulation qualities of traditional wood construction , no needfor caulking, ease of repair..
The defaults are in the aesthetic more thanthe practical. There is a difference in the feeling down belowin the epoxy saturation vessels and the plank on the edge vessel.It might be illusion with massive hanging knees now almost ornamental,and framing just a little vertical bulge against the interiorhull.
An epoxy hull does not smell like a workingwood hull and seems a little too sterile. The weight ratio andbalance has to be exact for performance and comfort.
Down below, four private cabins could bebuilt into the design as watertight compartments, one of whichwould be for the Captain. Two shared heads, toilet-shower compartmentscan be conveniently placed. The cadet crew would have more spaciousaccommodation but would still have bunk bed quarters.
The permanent crew would have two enclosedwatertight cabins forward with shared shower. The galley areawould be separate from the dining and recreational areas. Thesetwo rooms could become portable laboratories or studies in thecase of research charters. A fully dedicated navigation area couldbe built into the structure of the cabin.
Keeping the same physical dimensions theepoxy saturated Goldfield II would have her largest ratio of weightcentred down at the bottom of her keel. Her masts and gaffs couldgo along with the less weight above the waterline premise by beingcomposed of carbon fibre.
The original Goldfield was usually overcanvassed, which could be reproduced in the epoxy saturated GoldfieldII designs with the additional of Mylar topsails for increasedefficiency to windward. The working sails would be made of Dacron.
An epoxy saturated constructed GoldfieldII would cost approximately US$1.2 million.
Steel Construction
Probably the most costly of the four methodsof construction to be accomplished in the Cayman Islands is steelconstruction. Steel is strong and if, epoxy coated before anyoxidation can take place, steel can be relatively maintenancefree. But, an inspection and maintenance schedule must be strictlyadhered to.
Steel cannot be called a good replicationmaterial for a plank on edge vessel. It can be done but wouldhave to take an awful amount of time and precision to appear tobe the Goldfield under even slightly close scrutiny. But the weightcan be distributed as in an epoxy-saturated vessel. Steel doesnot have to be heavy.
Watertight can be built in, as can tanksand water ballasting compartments. Insulation and resultant condensationwill persist in steel structures. The same compartmentalisingthat was done in epoxy can be accomplished in steel.
The assets of steel construction are strength,little predominant scantling, watertight bulkheads, hull and deckconstruction as a unit, reinforced support structures, ease ofreparation, relative simplicity in construction (not in design),distribution of weight, low maintenance (if properly treated),availability of replacement material.
Some of the problems with steel as a constructionsystem are the strict adherence to a strict maintenance scheduled,condensation, and lack of insulation, electrolysis corrosion andaesthetic control.
Steel Goldfield II, built in the CaymanIslands, can cost upwards of US$1.4 million.
Glass fibre
The first choice for most Caymanians whohave been questioned on a material for a modern Goldfield hasbeen glass fibre. The choice is probably based upon the dependencyupon the material as a replacement for maintaining wooden vesselsin the Cayman Islands. A glass fibre boat can almost look likethe real thing.
The best method of building in glass fibrea vessel of this size would be to hand lay up the matte, glass,roving while rolling on the resin and to shoot a composite intothe inaccessible areas and corners. With glass fibre one can buildin cabins and watertight compartments, and with care the hulland deck can be bonded to become one.
Unfortunately, the larger the vessel, themore weight becomes a problem. To build a vessel of Goldfield'sdimensions an adequate thickness in glass fibre for structuralreinforcement weighs a lot more than the wood planks.
The other method is to encapsulate a lightermaterial that has structural integrity and low viscosity suchas carbon fibre. Insulation will always be a problem on a glassfibre vessel, but worms and rot generally will not. The interiorconfiguration could be the same as epoxy saturation or steel.
The assets of glass fibre construction arehull strength, watertight compartmentalising, integrated cabinstructures, hull and deck bonding, no rot or shipworm damage,lack of hull fasteners and resultant electronics concern, built-inreinforcing structures and ease of maintenance.
The problems of glass fibre constructionof the Goldfield start with the consideration that any uncoveredglass fibre can be deteriorated by the sun's ray and salt water,then there are the problems of condensation and corrosion, lackof insulation, noise, unavailability of survey reviewing, findinglocation of leaks, aesthetic appeal both inside and outside, withoutair conditioning it is uncomfortably humid to live aboard.
A glass fibre Goldfield II, built in theCayman Islands will cost upward of US$1.5 million.
The idea of the four alternative systems to the traditional forthe replication of the Goldfield II is to keep the progressionof the development of the vessel from the time she sailed andfrom the duty for which she was built.
If the Arch constructors were around todayand could build in plank on the edge or one of the other fourmethods the evident values and defaults of each would prove theirdecisions.