Extreme 840 Pontoon

Extreme Boats, based at the small rural township of Thornton near Whakatane, is going from strength to strength.

When owners Glenn and Diane Shaw bought the company seven years ago, it produced just two models. Now Extreme Boats construct hulls ranging from 5.5m up to 8.4m.

Solidly built and well finished, Extreme boats are gaining quite a reputation; the most recent accolade was winning two ‘Boat Of The Show’ awards at the last Auckland Boat Show for ‘Aluminium fishing boat under 6m’ and ‘Aluminium fishing boat 6-7m’ (see our January 2007 issue for a report on this hull).

With demand increasing in New Zealand and expansion into the Australian and New Caledonian markets, Extreme now has 11 staff, and its current workshop facilities are fully utilised. Further expansion is planned.

It is the company’s intention to semi-finish stock, so that final customising can be quickly achieved and the new owners’ boats supplied without too much delay.

Most of the Extreme line-up are monohulls, but a Scott Robson-designed 8.4m pontoon hull is also produced, and it was this hull I travelled down to the Bay of Plenty to trial on a fine, frosty winter’s morning.

The owner of the boat I tested, Red Fox, is Paul Sandford from Rotorua. He bought the 840 Pontoon as a family boat for water skiing and trout fishing around the Rotorua lakes, as well as for the sea journey from Tauranga to Whitianga, where he and his wife like to do stay-away trips.

Construction

The design of this pontoon hull is a little more complex than is usual with boats of this type. At 25° at the transom, it is a very deep V, to the extent that two planing strakes are added to each side of the bottom to get this heavy hull (approx 2000kg) up and boogying. The bottoms do not run straight up to the pontoons either, rather to down-turned chines below the pontoons. When the hull is on plane, it rides on these chines, keeping the pontoons clear of the water and reducing water drag on the hull.

A design item common to all the Extreme hulls is a self-flooding chamber running along the keel line, formed by welding a flat plate across the top of the keel ‘V’, forming a strong triangular section. The main reasons for this design, says Glen Shaw, is to add strength to the keel line, drain the anchor well, and form a convenient pathway to flood and drain the under-floor holds – rather than as a ballast mechanism, as the pontoons supply all the stability necessary when at rest.

The hull features 6mm bottoms, 4mm sides and topsides, and 3mm pontoons. Six full-length stringers help support it with the addition of the flat plate over the keel. Laterally there are frames at 1200mm centres.

The pontoons are separated into ten chambers, which are foam-filled, both as a further safety feature and to help reduce hull noise. In addition, four under-deck buoyancy chambers give about 3000 litres of buoyancy, according to the makers. The boat weighs about 2000kg, leaving around a tonne of reserve buoyancy – possibly the highest level of any recreational boat of this size.

Power and performance

This 2000kg hull is fitted with a 250hp Evinrude E-Tec outboard. This was the owner’s choice, largely influenced by the need for a good ‘hole shot’ when water skiing, and he has been more than happy with the low-emission, quiet, smooth performance of this engine.

The E-Tec 250 is a V6, hi-tech, direct-injection two-stroke outboard with ‘book rating’ top-end revs of 5800rpm. The test rig came close to that at 5700rpm while turning a 19” Rebel stainless steel prop. At these revs it was delivering 35 knots (64.8kph). A comfortable cruising speed was about 24 knots (44.5kph) around 4200rpm – a pretty good outboard-prop match for the hull.

The 25°, deep-V bottom cuts through the water like a knife and gives its best ride with the fine entry trimmed down.

On the plane, the pontoons ride clear of the water and the hull rides on its down-turned chines, reducing hull drag. A set of the excellent Volvo trim tabs (the controls are the easiest to use that I have seen) makes it easy to trim out any heel due to windage on the beam. At rest, the hull settles down onto the pontoons, negating any tenderness at rest you would doubtless experience in a standard monohull with this amount of ‘V’.

With an offshore wind under 15 knots and a run-out tide, the Whakatane bar was flat when I crossed with Nigel Merry, who has been involved in the marketing of these pontoon hulls. Further out towards Whale Island the sea kicked up to a short half-metre chop – a standard sort of condition faced by coastal craft. The 840 pontoon rode extremely well – a soft lander despite the planning strakes – courtesy of the deep V and the 2000kg hull. I was impressed with the ride and handling, and wished in some ways that we had struck really crappy conditions, such was the feeling of confidence the hull’s handling gave. Even quartering into the sea, the hull would hold its line with no hands on the wheel, and there was not the slightest sign of a broach. In short, an excellent performance.

Anchoring

It is possible to climb around the side of the cabin to get up on the bow, with footing facilitated by chequerplate decking, although the first bit of the traverse is a bit narrow between the substantial bow rail and the cabin side. A better access alternative is the large hatchway in the cabin roof.

Foredeck furniture includes a Sarca anchor permanently mounted on the bowsprit, a heavy crucifix-bollard welded to the foredeck, and a Quick anchor capstan with controls at the helm position. This feeds into the anchor well in the forepeak, which can be accessed through a hatch in the collision bulkhead. A further addition is a fold-down boarding ladder up near the bow – a useful way to unload or board passengers from steep-to beaches.

Layout

With a berth infill, the fore cabin will sleep two adults comfortably (a further bunk can be made up in the wheelhouse by lowering the small table between the two bench seats). The berths are low – just above deck level – giving plenty of head room.

The step-down drains to the tunnel above the keel and a flush toilet is installed under the central squab (it would be nice to see double hose-clips on this). The under-berth space is taken by buoyancy chambers, but some stowage is provided by side shelves, the padded faces of which double as backrests. Access to the wiring behind the console is through a latch-off plate.

Out in the wheelhouse, visibility is good from the helm, seated or standing, through the 6mm toughened glass ‘screens.

The steering is courtesy of the Hydrive Admiral hydraulic system, which seems to be the industry standard and is a pleasure to use, as is the smooth E-Tec throttle and shift.

The helm is well set up, with Navman Fish 4600 sounder, Tracker 5606 GPS, ‘retro’ white-faced dial gauges and quality switching gear all flush-mounted. There is plenty of dash room, which has a back lip and is marine-carpet lined. Overhead is a Navman VHF 7000 and Superworks sound system.

The seating is all bench seating – comfortable enough, and more flexible to different body shapes than many other types. Two bench seats on the passenger side have a small table between them, and under the forward seat is a mounting for the adjustable bucket seat that the owner’s wife prefers to use (the seat itself is stored in an under-deck hold when not required). Behind the helm seat is a squab that lifts to reveal a simple galley with a two-burner gas stove and a sink with a 50-litre freshwater system. Stowage is under the seat units and in side shelves on each side of the cabin.

A sliding, locking cabin door gives access to the cockpit, and two further bench seats are fitted against the rear of the wheelhouse, one of which houses the gas bottle for the cooker. The sealed chequerplate deck drains to a sump under the transom, from where water is removed by two 2000gph bilge pumps, one with a float switch and one manual. This is serious pump-out capacity if you need it. The cockpit edges are all smoothly rounded, and at the stern a transom walk-through with drop gate aids access out onto the large chequer plate boarding platform.

Large side pockets run the length of the cockpit, while a large locker in the transom wall is accessed through two forward-opening hatches. This houses two batteries with an isolation switch, the oil reservoir, a fuel filter and primer bulb.

Other accessories include: two stainless fire extinguishers and an EPIRB in the wheelhouse; wash-down hose; stern cleats; grab rails; a fold-down stainless boarding ladder; auxiliary bracket; and a fuel port situated outside the transom wall to prevent any internal spillage when filling the 380-litre underfloor tank. Internally, a guard plate protects the fuel line between transom and deck. Finally, an aluminium half-round rub-rail protects the hull from rubbing damage.

Fishability

A stable hull and chequerplate deck make a good basis for a fishing and diving platform. The gunwales supply mid-thigh support and most of the transom (except where the walk-through is) provides support above the knees. There is toe-room all around.

Further, an angler can get some bracing from the central bait-station. This boasts bait-boards, a saltwater sink to rinse your hands, and a hatch that allows you to ‘post’ smaller fish straight down to a ice-slurry-filled fish drum underneath. The unit is partly insulated to help preserve the catch in good condition. There are two fold-out bench seats on the side of the unit, and three vertical rod stowage holders on the rear face: a useful set-up that allows full access to the transom.

The six through-gunwale rod holders have the gimbal pins set correctly, and rod storage is boosted with a six-position rocket launcher on the cabin roof, also supporting a pair of cockpit spotlights. A livebait tank, suitable for mackerel, is under the transom step, and a locker for terminal tackle storage is fitted under one bench seat in the wheelhouse.

Divers are catered for with boarding ladder, big chequer-plate boarding ladder, grab rails and transom step-through.

A good, basic fishing layout that could easily be set up for bluewater trolling.

Trailering

A heavily-built hull like this needs a substantial trailer. Extreme Boats will be building about half their trailers and outsourcing the rest. The trailer the 840 Pontoon is carried on is a cradle A-frame design, braced and gusseted for extra strength, and hot-dip galvanised. It has tandem axles and leaf-spring suspension. Wheel rims are also galvanised and the bearings are protected by bearing buddies. The boat is supported by seven pairs of wobble rollers (and a single) per side, and Sens-a-brake electronic braking is installed. Other features include: a dual coupling; wind-down jockey wheel; submersible lights; and a dual-ratio manual winch. It was easy to drive on or off, and the tow weight for the rig is approximately 2.8 tonnes.

All-in-all

Solidly built and with a good level of finish, the pontoon construction of the Extreme 840 allows good stability and a high level of buoyancy (and hence, safety). It goes through the water very nicely indeed and shows all the signs of being an excellent heavy-water performer. Extreme Boats is happy to customise layouts to an owner’s requirements, and this boat fits the mould of a bluewater-capable overnighter. A great fish-and-dive machine.     

Specifications

Test boat courtesy of Paul Sandford.

	This article is reproduced with permission of New Zealand Fishing News 2007 - by Sam Mossman Re-publishing elsewhere is prohibited