The Old Sea Dog’s Gear Locker [45]

Pre-Emptive Surf Rolling, Kayak Hatches And Industrial Sewing Machines

The Old Sea Dog has long been concerned about getting trashed in the surf. Over the years he has slowly gained much wisdom and a few skills which have helped him to generally avoid ignominious and potentially damaging incidents. A good brace is, of course, essential. However, even the strongest of braces is useless in the face of a humungous, snarling wave which is about to drop countless tonnes of water on the foredeck. The OSD once used to charge full speed at these monsters and hope for the best. The best was usually a severe slap in the chest which bent him backwards over the coaming, followed by a savage pummelling in sand filled, murky water hopefully followed by a roll, which unfortunately was often just in time for another round of punishment. The worst… well, it doesn’t bear thinking about.

What to do? Initiate a pre-emptive roll, that’s what. Roll over in front of the wave, tuck into a set-up posture over the deck and let the bottom of the kayak take the force of the break. Instead of being hurled beachward, the kayak will more or less hold position due to the drag of the kayaker’s body being acted on by the seaward moving water (‘undertow’) beneath the wave. The kayak is generally pointing out to sea after rolling up. With luck, the kayaker will be able to pop over the top of the next wave. If not, well it’s time for another pre-emptive roll.

Timing is everything in pre-emptive rolling, like most things in life. Charging up the face of an approaching wave and getting airborne off the lip is one of the most exhilarating facets of kayaking in the surf. Many kayakers (including, it must be said, the OSD), are incurable optimists and wait until the wave is dropping on them and all hope is lost before rolling. This is too late. The kayak must be stabilised upside down before the wave hits.

There is another situation where pre-emptive rolling is of value. This occurs when surfing a wave and then attempting to carve off the face and head seaward before it breaks. Nothing fills the OSD’s heart with dread like the sight of a tube forming over the bow of his kayak while broadside to the wave. Instinctively, he hurls a massive brace into the wave, but to no avail. Up and over he goes, rolling with the wave. About 50% of the time, a small voice says, “Put your paddle out.” The paddle blade bites into the water under the wave and the kayak rolls up, now making good time across the front of the broken wave. This is a wonderful feeling, but the manoeuvre is almost never observed by others in the party, who scoff at the excited claims.

One day recently, the OSD got to thinking about wave dynamics. Waves in shallow water are fascinating things, and a lot is going on. Swell peaks up on entering shallowing water which is about 2 times the wave height. At a depth of 1.3 times the wave height, the wave breaks. The water then rushes shoreward as a wave of translation and may reform and break again if it enters deeper water in a gutter.

Before it breaks, water particles in a wave describe a more or less circular path, with the rotation in a direction having shoreward moving particles at the top of the wave and seaward at the bottom in the trough. Upon breaking, the orbital motion cannot be maintained and the unsupported wave top releases its energy by falling into the trough in front. Dumpers on steep beach slopes release energy quicker than spilling breakers on shallow slopes.

Since the whole wave form in a dumper is collapsing in a rotary motion towards the beach, a brace seaward into the wave is useless.  So, reasoned the OSD, why not roll inside the wave, in the direction of the beach, so that the rotary motion actually helps roll the kayak up? Why not indeed! The first time he tried the manoeuvre, it was in a 1.5 metre wave on the Tuross Bar. Although he made A BIG MISTAKE, the roll was successful. Upon inserting his paddle into the seaward moving water under the wave, he popped to the surface. His mistake was to attempt to trip the kayak by putting the blade on the beachward side of the kayak at the start of the roll. The paddle didn’t break, and his body suffered no lasting damage, but there was a lot of stress.

Far better to set up in roll position and lean towards the beach. Carving left, set up for a left hand roll. Carving right, set up for a right hand roll. Even if the off-hand roll isn’t normally very reliable, the technique works because the massive power of a paddle blade in seaward moving water combines with the rolling force of the wave on the hull. Voila! Right side up, every time (well, almost).

Of course, rolling in the surf, or anywhere else for that matter, requires watertight hatches. There is no argument that the best of all hatches is the 7 inch, round Valley Canoe Products model. This is followed by the VCP oval hatch and a wide variety of others, many peculiar to particular kayaks.

Wooden kayak designers have invented a number of hatches with varying degrees of water tightness. Some simply strap a piece of plywood over a hole in the deck with nylon straps and Fastax buckles. Weather-strip foam glued to the plywood makes the seal. Others use a wooden coaming and a wooden hatch cover, again with foam seal and nylon straps. The OSD favours a recessed hatch, seating on foam glued to a wooden lip. The hatch cover itself is the piece which was cut out to make the hole. Instead of nylon straps, he uses shock cord and, you guessed it, an OLIVE CLEAT.

Very early on in his kayak building career, the OSD developed his famous aft bulkhead-mounted VCP hatch. He simply couldn’t bear to cut a hole in the magnificent after deck of his cedar strip-planked kayak. It turns out that the bulkhead hatch has a lot of other advantages: ease of loading and carrying long items, extreme water tightness, ease of carrying spare paddle on after deck, etc, etc. Some are concerned that items may get stuck in the stern, but the OSD avoids that difficulty by tying a line to the dry bag.

At first, the OSD had trouble in fitting the VCP coaming between the deck and the kayak bottom, but solved the problem by slanting the bulkhead aft at the top. It is true that some old-fashioned, inflexible kayak designers from the NSW Far South Coast are very negative about aft bulkhead-mounted hatches, but they are vastly outnumbered by enthusiastic users of the system.

For much of his long life, the OSD coveted an industrial strength sewing machine. Then, several years ago, he scored a 1932 Singer with a 1 hp motor from a friend who paid $150.00 for three of them at an auction of Newcastle gear. There are quite a few old industrial machines around as globalisation shuts down Oz’s local garment industry. They are regularly advertised in the various Trading Posts. The OSD had his old Singer completely serviced in Canberra at Alan’s Sewing Machine Centre in Fyshwick. Alan, a dedicated sewing machine enthusiast, also sells used industrial units.

There is one major difficulty with industrial machines – they are FAST! The electric motor runs at a constant, high RPM. The OSD’s machine has a foot operated clutch which engages with little slippage – from 0-100 in about 1 millisecond. The skilled operator (not necessarily the OSD) taps the pedal with a calibrated movement for short runs. Long runs are easier, but require pretty precise directional control. The OSD got a smaller sheave (the smallest possible) for the drive motor shaft  which slowed the beast down by 50% and increased the already massive power at the needle.

Having gained the necessary skills, the OSD now zips through webbing, Velcro and heavy nylon in fashioning deck bags and other kayak paraphernalia which is strong enough to withstand any amount of pounding on the Tuross bar on the rare occasions when pre-emptive rolling fails. Happy Paddling!

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