I enjoyed immensely the articles by both Larry Gray and David Winkworth via the on-line newsletter edition (or is that the ‘E-zine’ now that you are a magazine?).
Both men seem to have a good insider’s view of the outside seam issue, adequately preaching their respective polemical viewpoints. I love the hair-splitting surrounding these seam-splitting semantics, as I believe there is educational value in these types of spirited discussions. As one who is largely insulated from, and ignorant of, southern coast politics – I’d like to offer some objective anecdotal evidence in connection with seam failure, critical leakage, and an alternative methodology for supplemental strengthening.
By way of introduction, I paddle mostly solo – in all-weather-all-year conditions – kayaking out of Victoria, British Columbia, Canada for the last twenty-plus years.
My 1980 Nordkapp is used in heavy surf, seal landings, storm paddling, tidal races/overfalls and extended expeditions. It has been rebuilt and polyurethane repainted three times now, including an additional oval hatch behind the seat, wrap-around seat bulkhead, foot pump, butterfly foot pedals, and a deep draft rudder. The dealer was originally questioned at the time of purchase, and reassurances were given that VCP boats conformed to the strictest ‘British Standard Marine Series’ code regarding ‘canoe’ construction.
Having already snapped a white water kayak in half in winter surf, my fears were hardly allayed regarding the lack of an outside tape seam on my new acquisition – the Nordkapp HS.
Within a year, nary a trace of the outside gelcoat ‘seam’ remained, mostly due to BCU rescue practice, encounters with BC’s plethora of logs kicked up during storm surges, and also due to gravel avulsion within dumping surf (when swimming in away from the kayak was called for).
Perhaps paddling in those particular venues were not quintessential seamanship, but the cosmetic damage was a rapid consequence nevertheless.
A year or so later, a sortie was made to an area renowned for sea caves and deep surge channels. With a calm day in the offing, a steep rogue wave later in the afternoon was a real surprise, broaching the kayak sideways in the 5 metre wide surge channel. As the wave passed, the bow and stern were left embedded in the channel’s opposing steep rock faces, while the sea receded by a metre or more below the hull.
With a week’s worth of gear and my own body weight buckling the kayak amidships, a huge chunk of the stern’s horn finally tore off at the back end of the kayak. This occurred when the kayak plummeted into the chasm, splitting a 30 cm length of the rear seam just aft of the round VCP hatch.
A year later, I was surfing 40 knot-plus wind waves over a shoreline reef near a tourist lookout, when a too-steep roller drove the nose deep into a submerged tide pool, catapulting the boat end over end.
The sudden jarring caused the aluminium footrest to break free from its fibreglass mounting tab, whereupon my hips lodged deeply within the confines of the hull’s interior (I am relatively short).
Unable to roll back up, salvation came from above by way of a visiting Washingtonian who rushed from his parked vehicle and proceeded to flip me back up once washed ashore. There was now a 20 cm split in the front seam just ahead of the front round hatch.
Upset, I stormed into the dealer.
Okay, it wasn’t normal paddling, but an atypical adventurer expects a lot more from his ‘British Heavy’ – given the amount of hype over allegations about tough construction standards.
Fast forward a few more years to the Oregon Coast. A surf meet was in progress, coming to a halt when swell started breaking at 3-4 metres. A young man, not me this time, continued to play – but bailed after being looped. His Nordkapp, with 300 lbs of water in the cockpit, cart wheeled through the surf zone, splitting all its seams and barely remaining semi-intact. Erran, who purchased his Nordkapp in Victoria, asked the dealer to see if the factory would cover the cost of a replacement kayak under warranty.
VCP wrote back, said no, and indicated it was the initial snap in the centre deck that damaged the integrity of the laminate. This caused the boat to behave like two separate pieces, and that the flexible, impact resistant woven fabric of polyester Diolen in the hull folded but didn’t tear and shatter like the deck, which used mat and saturated resin to create stiffness, yet conform to deck fitting protuberances.
Furthermore, Erran was told that due to interlaminar shear strength – which meant in this case the woven cloth seam was much stronger than the bond between layers, as was the case with the delaminated hull – such that upon folding, the inside seam pulled off like two long zippers each side.
At least, at the time, I finally understood why my own seam kept splitting and subsequently letting water in. I also came to appreciate that fixing split, delaminated sections of inside seam required removal of the entire offending old seam tape area. Simply glassing over old damage left the upper and lower half of the kayak at the seam line still moving independently of each other in a vertical plane.
I was told an outside seam would do the same thing if added and then over-flexed, so not to bother adding them.
The winter and spring of 98/99 proved to be the stormiest in decades. I went out storm paddling a lot in our cold BC waters (7 degrees Celsius). On one unfortunate occasion, the kayak was blown back to a different area of the beach in 45 knot gusts, where dislodged logs rolled about menacingly.
Dangerous, but not deadly like the open coast would have been, I surfed into the end grain of one big log, broached sideways, then was hit broadside before rolling, battering ram style, by a perpendicular log embedded in the sand and gravel.
The Nordkapp seams were hopelessly split, with the bulkheads arresting more severe delaminating. I actually did not realize how dramatic the damage was, and went paddling in a different area, subsequently floundering offshore with little reserve buoyancy as further delaminating and flooding occurred – but did return to the protected bay launch site by surfing wind waves, albeit in a sluggish manner. I now always check prior to re-launching after impact incidents.
With only a few weeks left before leaving on a preseason trip to the Mid Coast of BC with two friends, I worked feverishly to fix the kayak.
Consulting with individuals and listserver groups like Paddlewise, I determined it was best to chisel out and remove all existing and damaged inside seams, save for the distal ends fore and aft – which never delaminated and were largely inaccessible.
It quickly became apparent that VCP did not take the time to pre-cut the original, narrow interior seam tape. Rather than cut around the inside deck fitting mounds, the tape was simple glassed in lower down on the hull.
This only left 15 mm overlapping the deck join. No wonder side impacts so easily delaminated the tape joint (but I also understand the production requirement for this to be done).
After final preparation, I glassed in 25, 50, 75, and 100 mm cloth tape along all inside hull-to-deck joins (outside duct-taped to keep original shape), pre-cutting the 75 and 100 mill cloth tape for proper distribution.
A twenty-year-old kayak is obviously not ‘green’ anymore, so I substituted fibreglass resin with quality two-part epoxy resin. I then decided to screw convention, and taped-off with masking tape a 25 mm outside seam line, sanding the defined area of exterior gelcoat with a coarse grit sandpaper.
Using epoxy resin again, I added two layers, done one day apart, applying the 25 mm cloth tape in as straight a line as possible. For cosmetic purposes, I masked off a 30 mm line, and then brushed on the entire length a thin slurry of powder-thickened epoxy – working one side at a time up on edge.
By pulling off the masking tape just prior to the epoxy going gelatinous, a smooth, rolled edge gave the usual ‘flowcoat’ polyester gelcoat look, covering the textured cloth tape, and giving it a bit of protection.
I then painted the new exterior seam with black paint. As an experiment, I tried prying off the seam with a chisel, but it was impossible. Epoxy resin is a tenacious bonding agent.
After another week adding an exterior and interior keel of UMHW plastic and ash respectively (bolted through the hull), I left for the extreme weather of the Mid Coast. On day 5 I hit a reef in a rock garden while surfing at 7 knots, with no damage, other than cosmetic. The new seams were holding well.
On day 7 the three of us ill-advisedly decided to cross the open waters of Queen Charlotte Sound, in order to get a suffering member of the team back to the protection of Vancouver Island’s east coast (he had been ill-prepared for the minus 5 degree evenings and cold, heavy seas and constant SE gales).
The two hour paddle to the mid-point Storm Islands from Cape Caution turned into an 8 hour ordeal (and a 6 hour tow for me with a stricken paddler) when an unexpected gale and 3 knot unknown persistent ebb swept us away from the intended island and all land.
The other member’s North American kayak eventually split a seam in the heavy, difficult seas, flooding it to the knee tube. His kayak had inside and outside 50 mm taped seams, but I don’t believe the manufacturer had prepped the outside properly. With the other paddler hypothermic, a number of Maydays were issued, entailing a complex air-sea rescue scenario.
Subsequent transfers from a first response fishing boat (vessel of opportunity) to the tasked Coast Guard rescue boat witnessed the other two kayak heavily damaged while being pulled over the railings of both craft. My kayak suffered only cosmetic damage by over-taxed SAR personnel.
I make no apologies for the type of paddling I do, the abuse my kayak is subjected to, or the predicaments I get myself in to. I do feel I am in the invidious position, however, to recommend that kayaks subjected to above average use would benefit from adjunctive seam strengthening. This is, however, tempered by the fact that most ‘interior-seamed only’ sea kayaks provide years of trouble free enjoyment for almost all kayaker’s paddling a variety of rough coastlines around the world, and that exterior seamed kayaks, done on the cheap, provide little further benefit. For the ‘do-it-yourselfer’, adding outside seams, prepped accordingly, and done with epoxy resin, add immeasurably to an already well-made kayak. I stake my life on that.