Stabi-Craft 593HT

Perhaps the biggest challenge designers and manufacturers of aluminium boats face is producing a hull which has above-average stability combined with a soft ride. So far, GRP boats win hands down in the ride department, as technology hasn't yet defied the laws of physics.

However, every year tinnies get a little better. Plus, a heck of a lot of people love them for their other advantages, especially their light weight, towability and ruggedness.

KIWI EVOLUTION
One of the leaders of the evolutionary charge is New Zealand boatbuilder Stabi-Craft. Reviewed here is the company's 593HT (Hard Top), a little brother to the 753HT we tested back in the February 2001 issue of Trailer Boat.

The smaller 593 is just as impressive, and in some ways, even better, particularly in the way it rode over the half to 1m chop encountered on Port Phillip Bay during the test.

The boat probably needed rougher water to really show its true colours, but it did perform similarly to its big brother - even better in some instances, particularly in a cross-sea.

But before going into that, it's important to understand the history and dynamics of the hull shape, which is unusual to say the least.

At the southernmost corner of New Zealand lies Foveaux Strait, a notoriously stormy stretch of water that separates Stewart Island from the South Island.

In 1986, two local fishermen approached the fledgling Stabi-Craft Marine with a brief to design a small, rugged, unsinkable pontoon-style boat, so they could fish in almost any conditions and get back to the mothercraft with their catch.

The first-generation boats were designed with standard round pontoons, but the second-generation pontoons have a deeper cross-section which gives more freeboard. They are also angular and slimmer, providing more internal beam, buoyancy and stability.

Underneath, the pontoon design features two-stepped and wide chines which provide lift, responsive cornering and a drier ride.

Two separate pontoon - or sponson - sections on either side of the cabin area are watertight for positive buoyancy and safety.

The centre hull is a conventional vee-formation with a 20° deadrise at the transom. The testboat was fitted with a Mercury 150 Optimax DFI two-stroke, swinging a Vengeance 17-inch prop on a high-mounted pod.

The bow has a very solid split aluminium bowrail, which meets the bowsprit and is easily accessed either around the wide side-decks or through a smallish but adequate hatch, which can be opened from top and bottom, in the cabin. Gone is the swing-down step arrangement of the bigger boat - probably a good idea at the time - and with it the anchor-rope jamming on retrieval.

The cleat-style bowpost and sizeable covered anchorwell are an improvement on the larger boat too, which had no hatch and a small uncovered anchorwell.

Looking at the boat from the outside, its cockpit depth seems shallow. Quite to the contrary. The step-down from the gunwales is quite deep, and while the testboat did not have a transom door fitted, it is now a standard feature.

The gunwales are extremely wide with substantial non-slip strips, and there are plenty of handholds on the hardtop, windscreen and deck for the walk from the cabin to the bow. The thigh-height depth of the coamings is exceptional.

MIX AND MATCH
The open-access fibreglass cabin features a cloth-covered V-berth with basic storage underneath for lifejackets. Serviceable carpet lines all surfaces. The deck is the same level as the cockpit sole and is checkerplate aluminium. Sidepockets are long but very narrow, obviously squeezed by the wide deck walkways.

The pedestal helmseat is ok, but perhaps a better option provided by Stabi-Craft is an aluminium box that is welded to the coaming and sits high off the cockpit sole, making it very easy to hose down.

Engine controls are a little awkward to get at, as they are mounted forward and in front of a cabin pillar which intrudes into cabin space and restricts arm movement. The trade-off is a large storage pocket below your right elbow.

Well-positioned on the instrument panel is a Garmin GPS 180 plotter and a Garmin Fishfinder 160. Gauges are perfectly positioned and visible, and a 27MHz radio and tape-player are also mounted on the instrument panel.

The switch panel is on the left behind a small helm. The very wide dash is carpeted and the crew seat has a footrest and grabrails for the left hand on both the side cabin pillar and coaming, as the port bulkhead is substantially cut away for easier access to the cabin.

The huge screen on the hardtop consists of three panels, the central one is safety-glass fitted with a wiper and the corner curved sections are acrylic, all tinted. The hardtop's two side-window panels were fixed, but sliding windows are an option. The large hardtop is fibreglass and has a generous cockpit overhang. Its hardtop height is excellent.

READY FOR ACTION
Topside there is a black aluminium rocket launcher for four rods - which is a stretch to reach - mounts for twin aerials, spotlight, nav lights and GPS antenna.

The self-draining cockpit is large, and I just loved the wide, painted gunwales - with two quality rubber-insert stainless steel rodholders and two out-of-character plastic ones - and deep coamings. The checkerplate sole provides sure footing and sidepockets are long and wide.

There are no underfloor storage compartments apart from the fuel tank. Cabling from the controls to the motors and batteries looked a little vulnerable exposed in a concertina hose zip-tied along the starboard side beneath the sidepocket. However, I am assured that later boats are now fitted with an aluminium protection plate over the conduit.

The transom features open, but off-the-floor and easily accessible, twin-battery and oil bottle compartments either side of a small, but handy, open bilge. A chest-height removable baitboard mounted mid-transom on a skiing/wakeboarding U-bolt arrangement was great to work with, as was the deckhose.

Beyond the transom is an almost full-width panel to give the motor swing-up room and a boarding platform. On the port side of the engine pod is a boarding platform with a swing-down, solid aluminium ladder bolted to it. This is great for boarding, except the steps are positioned too close together unless you have very small feet.

Performance is this boat's forte. It absolutely flew downsea, and we achieved a top speed of 67.3kmh at 5200rpm through a half-metre chop, while comfortable cruising was 52.7kmh at 4000rpm. In cross-seas, the occasional wave would thump into the sponsons with a bit of a whack.

Stability is excellent, full-stop. Four big blokes on one side of the boat produced only a minor list.

The Stabi-Craft is a well-built boat. The metalwork is good, the glasswork smooth and the paint job first class. As the testboat belonged to a customer of MY Marine, a few paint chips were expected, particularly on the metal, but it was tough finding anything more than superficial scratches.

The Stabi-Craft was packaged on a tandem axle Dunbier multi-roller trailer, but is light enough for a single axle, according to MY Marine.

The Stabi-Craft is not the prettiest boat you'll ever see, but if you're in the market for a tonka-tough tinnie that works, make sure you check out this boat and its brothers.