construction

MD set its sights very high for the Buzzards Bay 33.  She was to achieve a combination of comfort and performance never before achieved by a production vessel.  We knew we would have to break new ground, marrying a new hull shapes with advanced composite construction.  In order to test and refine the design, it was decided to build the first vessel without the use of fixed tooling (molds) so that we would not be financially locked into a design before it was refined.  To the right is the proto-type's hull, up-side-down, under construction in what is called a "one-off" method.  Utilizing similar materials to that of the production boats, she was built with Core-cell coring, and uni-directional e-glass fabrics. 

First Buzzards Bay Launched

mold construction

polished mold ready for production

Once the gel coat is carefully distributed through-out the mold and a measured drying time has ended, lamination of the fiberglass begins, first with what is called the skin coat. This is a thin layer of fine fiber strands orientated randomly, called mat. This layer serves to provide proper adhesion of the gel coat to the relatively coarse structural fiber glass layers to follow. The mat also reduces "print-thru" which is a cosmetic condition whereby one can see the actual pattern of the coarse weaves of the underlying structural fiberglass layers showing thru the gel coat  Mat as compared to structural fiber-glass is very resin rich, making it weaker and heavier. For this reason MD uses enough Mat to get the benefits, but no more. Helping in this regard, the mat that goes into an MD is laminated by hand into the hull, as Bruce is doing in the picture to the right.  This method, as opposed to spraying the mat via a chopper-gun creates parts of consistent quality and performance.

Now the build up of the structural fiber-glass layers that give a parts its real strength can begin.  To the right you see Bruce and Lorne carefully wetting out the fiberglass that runs across the tunnel.  All the tunnel fiberglass layers start in one hull, travel across, and descend down into the opposite hull, with large fiber overlaps organized around the tunnel radius to build up strength in this highly stressed area.  The fiberglass used is uni-directional, with all fibers within a particular layer oriented in a single direction.  This type of fiberglass has a higher strength to weight ration than woven types, and is more resistant to fatigue. The resin used to saturate the fiberglass through-out the Buzzards Bay 33's hull and decks is a quality pure vynilester resin.  This resin has a higher tensile strength and much higher fatigue limits than the typical poly-ester resins most often used.  This not only makes the Buzzards Bay 33 stronger, lighter, and more durable, but also significantly increases her resistance to blister.

Here, Lorne is applying core adhesive with a notched trowel onto the hull tunnel.  Core-cell foam core, pre-cut with an identifier for efficient placement, is assembled, and then covered under a sealed plastic sheet.  The air is then sucked out, enabling atmospheric pressure to push the sheets of foam coring into the core adhesive. This is known as "vacuum bagging".  Installation of coring in this way eliminates voids between the core and the fiber glass skins, which can cause a build-up of moisture, leading to rot in the case of balsa cores, possible de lamination, and definite weight gain in the case of foam cores.  This type of construction is more costly but creates a boat you can trust with lasting value.

Bruce, Rob, and Lorne vacuum bagging foam

The hull is pulled from the mold

An exciting day for all of us.......every time.

The forward bulkhead under construction.  The bulkhead is built on a smooth surface to provide a molded gelcoat surface in the stateroom and head. This bulkhead is cored with Core-cell and uses unidirectional fiber-glass saturated with vinyl-ester resins, just like the hull. This bulkhead too is built with the vacuum bag process as described above.  At this time all sub structure is built outside of the boat, such as the supports for machinery and tanks, and prepared for installation

bulkheads installed

Lorne is smoothing the inside fiberglass skin in preparation for gelcoat  We choose to hand finish most of the interiors of our boats, as opposed to covering with additional molded parts.   This is a lighter way to build a boat, but our owners benefit in terms of increased fuel efficiency and weight carrying ability.

stateroom closet installed

Installation of mechanical systems now begins. MD specify's its fuel tanks come with a welded mounting flange.  This flange allows the tank to be thru-bolted to the tank shelf, which had galvanized steel flat bar laminated installed during construction.  This mounting technique eliminates the need to pour foam around the tank, which tends to hold moisture, causing corrosion and early tank failure.  Foaming in a tank also makes it quite difficult to remove if ever there is a problem. Shown to the left is one of the gas tanks for our Buzzards Bay 33OB model. Gasoline tanks do not have clean-out ports, but the diesel fuel tanks have one fore each baffled space.

installation of oversized rigging tubes

installation of propulsion support systems

deck and pilot house, fitting Core Cell foam coring

All of the remaining parts, including the cockpit, deck / pilot-house, coach roof, and furniture are molded in parallel operations.  Above is the deck and pilot-house unit under construction.  1" thick Core-cell coring is vacuum bagged, pressed into the underlying core adhesive.  This construction method eliminates the possibility of moisture migrating thru the deck from failed adhesive seals around surrounding deck hardware.  If the adhesive does fail, there is no place for the water to travel and with our use of Core-cell foam coring, there can be no rot even if the moisture could migrate.

the deck meets the hull for the first time; another exciting point

On Completion, the proto-type was launched and fully evaluated on the demanding waters of Buzzards Bay and beyond.  From seat height, to sight-lines, performance, and comfort, all were tested in a variety of weather   and loading conditions.  We then displayed her at the Newport International Boat Show in order to get some feedback from actual buyers.

proto-type testing and evaluation

Tooling was constructed at Sea-Glass Technologies, of Bristol, RI.  These accomplished craftsmen have produced tooling for C&C, Tartan, Ted Hood, Hunt, and now MD.  To the left is the hull plug receiving final fairing.  The substantial investment in high quality production tooling has allowed MD to efficiently deliver a high performance vessel with a yacht quality finish, every time. 

First, the mold is cleaned, waxed, and buff. The finish of the final part is only as good as the finish of the mold used. Here you see Lorne, resident finish guru, applying gel coat to the hull mold. An assistant (outside the picture frame) is needed for this job, to handle spray hose around the mold, and to continuously check how much gel coat is applied to the mold, giving feedback to Lorne so that he can make adjustments to his technique. The gel coat used here is a Cooks Composites' ISO/NPG formulation, which is the best gel coat money can by. This gel coat is particularly resistant to stress cracks, blisters, and fade. It costs more up front, but is a value in the long run.

Lorne applying gel-coat

Bruce applying the skin coat

Bruce and Lorne applying structural layers

Lorne applying core bond

The vacuum hose penetrating the plastic sheet

Once all the coring is installed and the inner layers of structural fibers installed, the workers perform a light abrasion of the interior fiber-glass surface, which makes for higher quality bonds of the coming structural supports, as well as smoother and easier to clean bilges for the owner.    Next, the hull part is picked up to ensure separation of the part from the mold.  The hull is then placed back in the mold in order to maintain its shape, while it awaits bulkhead installation. 

bulkhead construction

Here the major and minor structure has been fitted and fiberglassed into the hull. Next, the anchor locker, machinery spaces, and bilges receive a bright white gel-coat finish prior to mechanical systems installation

Lorne hand finishing the cabin interiors

Cabinetry is built off of the boat and finished before installation into the boat.  This is a much more efficient way to build, we do this as much as possible.

head vanity under construction

begin mechanical installation

To the left, Robby and Lucas are installing the oversized rigging tubes. These are PVC pipes, 3: 4" in diameter.  Two in the starboard hull and one in the port hull carry the engine harness', navigation electronics, and most equipment power and control circuits.  In the end, there is room to spare for additional wiring from equipment added after construction. An MD owner tends to be an equipment connoisseur who may find it hard to leave their boat alone.  Our rigging system makes additions easy.

Now all the systems are installed, wiring run and secured, hoses and fittings installed, and all equipment.

installation of battery charger and wiring

vacuum bagging the deck coring

coring removed around thru-bolted hardware

furniture is molded; here's the galley unit

With the systems installed and interior surfaces finished, the decks are installed.  Here, the deck / pilothouse unit, a one-piece molding, is being installed.  To do this, a number of attachment points, such as the bulkheads, cockpit, dash, etc is tailored for a perfect fit, then laminated together for a one-piece, unitized structure.