Mac 420 Cuddy

Few of humankind's many groundbreaking inventions have impacted on the world like plastic. Plastic has found its way into virtually everything we touch, including most production boats. Now, that most prolific of plastics - polyethylene - is shaping the way we take to the water.

While plastic boats are nothing new, the last few years have seen a revolution in rotomoulded polyethylene watercraft. Today, you can buy plastic fishing boats made in Queensland, plastic longboats imported from Indonesia based on a traditional dugout design, and a plethora of plastic canoes, kayaks and dinghies from all over the world.

The subject of this story is a plastic boat with a big reputation from across the Tasman. Kiwi company Galloway International, one of only three firms worldwide contracted to make playgrounds for fastfood giant McDonalds, has been rolling out its aptly-named Mac Boats for more than a decade.

Rotationally moulded from virgin Australian-made polyethylene - the non-recycled stuff ensures consistency - Mac Boat are like their fast-food namesakes. All the models from a 2.1m dinghy to a 6m Sport Cabin, the largest rotomoulded boat in the world, can be considered boats to go, built to a price, to satisfy the masses.

While it can't claim to be eye candy, the 4.2m Mac Cuddy I drove was an eye-opener. A rough diamond, it answers the call of today's don't-mention-the-word-maintenance kind of boatie. But there was more to the boat than a hose-out hull.

Because most forms of marine growth have trouble adhering to polyethylene, these are great boats to leave in the water. Polyethylene also comes in a broad spectrum of colours from safety yellow to camouflage green and hot pink. What's more, the material has positive buoyancy and it's UV-stabilised for a long outdoor life expectancy.

All aspects of the boats are backed by a five-year warranty and boating mishaps are easy to fix. Gouges, scrapes and tears can be repaired in a matter of minutes using a plastic weld, a device used by most large panel beating yards.

But to my mind, the best thing about the Mac 420 Cuddy was the way the boat absorbed impact. The hull produced one of the quietest and most forgiving rides you will get from any boat of this length. Only a RIB can match it for smoothness.

And in respect to impact resistance, the local importer has a section of hull that took a direct hit from a 12-gauge shotgun. The outside skin is peppered with pellets, but none penetrated the inside of the hull, which is nice to know the next time you're unlucky enough to be the victim of ramp rage. This demo piece is intended to help win contracts with the armed forces, but nicely illustrates the toughness of the material.

DESIGN PHILOSOPHY
Despite the profusion of plastic watercraft, Mac Boats claim to have the only pontoon-style polyethylene boat. To my knowledge, the company also has the only polyethylene boat approved by the US Coastguard.

The Coastguard endorsement was obtained by foam filling the hull, which is rotomoulded to a thickness of 10mm using computer-controlled equipment. The bow and stern sections are filled with the two-part liquid foam for positive buoyancy with a full payload.

Importantly, the outboard motor's powerhead will remain above water when the boat is swamped, says the importer. But whether the boat remains upright or inverts in rough water is another thing.

Having said that, Mac Boats are exceedingly stable due to their pontoon-style shape. The company has photographic evidence of one of their 3.6m pontoon dinghies remaining upright with three people sitting on the gunwale. This 4.2m cuddy was stiff as a board.

POLY IS NO CRACKER
Because polyethylene boats flex and absorb a lot of impact, they need to be strengthened. The walls on the Mac 420 have a step or clinker moulded into them for added reinforcement. Internally, the step allows you to place a padded board across the width of the cockpit to boost seating capacity.

A unique swallowtail transom, incorporating non-skid tread steps either side of the outboard, stiffens the aft sections and benefits buoyancy. The not inconsiderable weight and leverage generated by the 50hp Mercury outboard was supported further by a powder-coated aluminium bracket bolted to the longitudinal plastic ribs moulded in the hull.

The engine bracket also created an aft storage well for the boat's 12V battery as well as access into the bilge where a small pump is mounted. While the boat isn't self-draining, the factory is looking at offering a venturi system. Presently, if you plan to leave this boat in the water you will need to fit a float switch to the bilge pump.

Treated kauri marine ply is used as flat flooring topped with (optional) marine carpet before being screwed into place. However, no use was made of the underfloor areas even though there appeared to be room to recess a central storage hold and/or fuel tank.

The boat's portable 25lt fuel tank sat annoyingly in a transom corner. But we realised later that there was room to carry the tank under the passenger's side seat box screwed to the floor.

The lid on the aft end off the seat box provides a third bumrest and lifts off to grant access inside to a stack of lifejackets in this instance. The optional swivelling bucket seats mounted on the boxes were moulded from plastic, of course, but were stiff to spin around.

The helm seat was mounted on a smaller seat box that will come in handy for stowing mooring lines, fenders (not that you need them with a plastic boat), a torch, rain jacket and so on. There was a small partition for carrying the anchoring hardware in the cuddy cabin, but no hatch. As it was, you had to anchor over the side.

There was also no provision for storage inside the cabin, but room for a plastic fish tub with lid that could double as an impromptu seat. You might also consider adding a canopy and factory-fitted rod holders. A glovebox, skipole and high sides are among the listed options.

ON THE WATER
While the 4.2 Cuddy is a stable boat thanks in part to its generous 2.2m beam, of which 1.7m is useable space inside, it is the buoyancy of the pontoons that provide the big plus. When you stand on one side, the hull heels only so far before the pontoons provide resistance.

Offshore, two of us hardly rocked the boat when standing on the same side. And despite just 11° of deadrise, the hull was super smooth across the 1m swell, wake and small wind waves.

Yet I would strongly advise that you fit the optional high sides alongside the helm seats. While the cuddy cabin, swooping foredeck and high pontoons provide plenty of lift and freeboard in the bow, the transom and sides are quite low with just 600mm of freeboard.

When reversing you can put water in this boat and with the weight of several people at the transom it seems that you could dump a wave aboard. But the low freeboard is, I'm told, one reason the boat appeals to divers. And buoyancy is such that an on-water battery business uses this hull to carry and deliver its powerpacks.

Underway, the Mac 420 was pleasant enough. Vision over the cuddy cabin is clear when seated and a small reverse perspex lip that doubles as a grabrail ably screens the wind. While the helm seat is fixed in place, the driving position including sports wheel and throttle was in the right spot for me.

Driving standing provides a different sensation - that you are quite high up. As the boat leans hard into the turns, passengers and skipper need to hold on. Fortunately, a big stainless steel grabrail traces the inside edge of the cuddy cabin and there are plastic grabrails back aft.

But driven as it was intended, the Mac 420 Cuddy was predictable. I certainly didn't feel intimidated travelling offshore to the wreck of the Valiant at the entrance to Broken Bay and back home again.

PERFORMANCE
Spinning a 14in three-blade alloy prop, the three-pot Mercury 50 propelled the Mac 420 to 50kmh at 5200rpm. The boat holds plane down to 26kmh at 3000-3200rpm.

Among the most efficient cruise speeds are 32kmh/3500rpm, 38kmh/4000rpm and 42.7kmh/5000rpm. At these speeds, the boat throws the water about and is rather wet quartering the wind. Then again, the hull measures just 4.20m.

A big little boat, the Mac 420 has a passenger capacity of five adults.

With a 50hp and a family of four or less, the 200kg hull will get along just fine. The boat is also an easy tow for a small car and economical to run. And it will fit in a garage or under a tree in the backyard.

And when the boat reaches its shelf life some decades down the track you can put it out with the recycling. Surely this point alone makes the plastic boat one of humankind's smarter inventions?