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I figured this out years ago when finishing Suilven II, a Wharram Tiki 26 catamaran. We needed a good watertight seal on the forward lockers. These were exposed to the occasional dollop of fast moving “green water” so the seal needed to be good.

Commercially manufactured seals weren’t readily available so I decided to improvise using silicon sealant, molded to the gap between the hatch and the deck coaming. The result was a perfect seal. It was so good that a fall in temperature would lower the pressure in the locker and make the hatch hard to open!

When I finished my Storm LT kayak three years ago I decided to use the same technique to form the fore and aft hatch seals, rather than use a soft rubber seal. It has worked very well, keeping water out during practice wet-exits.

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The hatch has been positioned, and the silicon pushed out. Allow a day or two to fully cure.

Here’s how to do it.

Clean up and degrease the flange where the hatch will sit. It’s important that the silicon sealant bonds well to this surface.

  1. Tape of the exterior surfaces where you don’t want extruding silicon to stick.
  2. Liberally coat the underside and edge of the hatch with a release agent. I used Pathway Polymers “Synlube 531 Release Agent” simply because I already had a can. Whatever release agent you use, I strongly recommend a trial with the silicon rubber you intend to use (GE Tub & Tile 100% silicon in my case). A stick up could be very tricky to undo!
  3. Squirt a generous bead of silicon onto the flange.
  4. Carefully place the hatch into the exact position. Push it down to extrude the sealant. You may want to improvise some spacers for exact positioning. It has to right first time!
  5. Allow the silicon to fully cure then pry off the hatch.
  6. Trim the surplus silicon with a sharp utility knife.

You now have a durable silicon rubber seal that exactly matches the shape of the hatch. The fit will be so good that you may need a handle or pull cord to remove it.

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Nylon straps that can be tensioned hold the hatches in place.

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Patrick tries the long-arm scraper with steel blade.

If you own a boat for long enough you may be faced with one of the most daunting challenges a DIY boat owner can have… stripping old, cracked and peeling antifouling back to a bare hull.

My time was up this spring. I knew it was coming and after Karen and I purchased a C&C 30 last fall we realised this job was looming on the horizon. During the pre-purchase haul-out and survey it was clear that the task was imminent. She’s a fine, strong boat and the price was right so we decided to bite the bullet and get on with it.

I spent some time researching “how to,” and of course there are plenty of opinions and advice on various forums. But it’s difficult to separate the opinions from the raw “truth.”

Big factors will be time and money. You will probably have one or the other and if you have both then count yourself as being very, very lucky but even then care is needed. Avoiding charlatans, gimmicks and rash promises can be tricky. And even with all the money in the world you may be unable to nail down a reliable shipwright or out-of-work yacht bum to do the grunt work – especially in the spring when they are in peak demand. If you are flush with cash then this is probably not for you anyway as you probably have a spanking new boat that won’t need serious bottom work for many years to come.

Skye Five spent the winter in Captain’s Cove Marina in Ladner, BC. The Marina allows owners to freely work on their own boats. Skye Five was hauled on the 15th March and I decided to rent the yard’s pressure washer to clean the weed off. Lucky I did, as I discovered that if I held the nozzle close enough, not only did the weed and barnacles come off but large slabs of old antifouling too. With the yard’s approval, I continued for 3 hours with only a five-minute break to put more gas in the machine. My shoulders and arms were killing me after grappling with the writhing hose but at the end of it I figured I had removed 60 – 70% of the horrid stuff without getting much on myself. I had clogged the drains but I felt victorious. The yard manager was pretty amazed too.

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Pressure washing removed a lot of loose antifouling.

The euphoria was short lived, however, as I began to tackle the remaining 30 – 40% the following day. I had help. Karen’s son Patrick used a day off work. Little did he know what he might be getting in to. Between the two of us we spent an exhausting 16 hours attacking the bottom, armed to the teeth with various scrapers. These fell into two camps. The very long handled variety with steel blades – very effective but the blades required sharpening every 10 minutes. The other, somewhat shorter scraper came with a reversible tungsten carbide blade. I used two carbide blades for the whole project, eventually abandoning the steel scrapers.

Twenty-five hours of back breaking, shoulder burning work was needed to get the hull ready for final sanding. I’m nudging 60 and starting to feel it. Young studs may not be so challenged. It’s filthy, hot work. You need all the protective gear – goggles, dust masks, safety glasses, hazmat suit (well, painter’s coveralls). It then took 10 hours of sanding to prepare for paint. Eighty grit worked the best. The dust was extraordinarily obnoxious and had a tendency to find its way into everything. You have to “decontaminate” at the end of each session to avoid the worst. Once kitted up I would work non-stop for 3-4 hours because I just didn’t want to go through the rigmarole of getting the gear on and off.

Fortunately, the weather was unbelievably benevolent for Vancouver and I had five days of sunshine and temperatures in the low teens – perfect!

So, after 37 hours of probably the most grueling work I have ever done, I stepped back to admire a job well done.

Was it worth it? Are there better or cheaper alternatives? Well I did look into using paint stripper. There are some soy based products out there but none I could find in Vancouver. I could have brought some in from the USA but I had left it too late.

As for materials, the cost of 40 sanding discs and 3 scrapers hardly touched $100. Paint stripper would have been way more expensive and I still would have needed to sand the hull.

The yard also warned not to use soy based stripper if the temperature was below 20C. They had seen expensive failures last year using a soy based system – the weather was too cold and a second application, applied by a contractor at extra cost was needed. I was told that if conditions are right it works well.

Web searches showed some pretty mixed reviews on all types of paint stripper. There are blasting options but these are not generally DIY and therefore expensive.

I could have just sanded, preferably vacuum sanding, but I’m not sure that would have been any faster. You also need to apply a lot of pressure for rapid removal and believe me, that is not easy when working above your head, sometimes crouched, sometimes kneeling and sometimes sitting. Given the pain it was definitely a case of “mind over matter.” At the end of it I gave myself a pat on my very sore back as I had endured way more discomfort than I ever knew was possible.

The other really, really big consideration is the impact of the dust created using scraping and sanding. The yard, quite rightly, insisted that I tarp the hull off to contain the dust. A roll of construction plastic and some Tuc tape worked very well and I did manage to remove the tape without leaving a lot of goo on the boat. There was very little wind which helped keep the dust in one place. The last thing the yard wanted was a fine red film on freshly detailed boats. I think I met their requirements – at least there were no complaints.

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Almost done! The tent contains the nasty red stuff.

Well, it took 37 hours of scraping and sanding. If I hadn’t struck it lucky with the pressure washer it would have taken considerably longer. It’s probably the cheapest way to do the job by far – if you are providing your own labour. Also be realistic about the length of time it’s going to require. Yard space is not cheap. Keep in mind that if you start out scraping you can switch to another method if it doesn’t work for you.

It’s just starting to rain so the new antifouling will have to wait. Right now I’m heading off for a well-earned beer.

During a recent visit to the Fowey, Cornwall – the south western peninsular of the UK – I came across this gorgeous cutter. Unfortunately I don’t have any details (no name visible from the dock) and no one was available for comment. Maybe someone out there knows more..? It took my breath away!

Seen in Fowey, UK, May 2015

Seen in Fowey, UK, May 2015

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Also seen entering the harbour – a restored working boat no doubt.

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The author's freshly finished kayak on Swan Lake, Vernon, BC.

The author’s freshly finished kayak on Swan Lake, Vernon, BC.

After some 400 hours of pleasurable work, I launched my kayak on August 3rd. I’m very happy to report that my new boat meets all of my expectations. She is fast and capable and when I get back to the ocean I’m sure she will also pack a good expedition load.

Rainbird, the 33’ wooden Bill Garden sloop which had been in my life for 5 years was sold at the end of June. As my home is in the BC Okanagan, keeping a boat on Vancouver Island was becoming a strain. Getting there involved a 550km road trip and an expensive 2 hour ferry ride – typically 11 hours door to dock. I was also spending way more time on maintenance than sailing. Besides, Rainbird was as much Jilly’s boat as mine and after she passed away in 2012 my whole world changed.

I certainly haven’t lost my love for sailing and wooden sailboats, but it’s time to try something different, especially as the cost of keeping a boat on BC’s coast makes it tough for budget conscious sailors.

I will continue posting kayak building tips. The process wasn’t difficult but then I have 30 years of building experience to draw on. Hopefully I can help new builders save themselves a little time and money.

Finally I would like to thank Vaclav Stejskal of One Ocean Designs for his beautiful Storm LT design and excellent plans and manuals. Armed with these you can’t go wrong and my comments are only intended to show other slightly different ways of achieving the same ends with the tools, materials and experience you have at hand.

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The swept bow and stern creates clamping challenges but splitting the strips over the curved portion with a utility knife is a great help.

The swept bow and stern creates clamping challenges but splitting the strips over the curved portion with a utility knife is a great help.

The hull is progressing well with few problems. I haven’t used the traditional bead and cove method but instead used plain strips and beveled one edge of each strip to achieve a good fit. I used polyurethane glue rather than white glue making final clean up very easy.

You might think that beveling one edge of each strip is difficult and time consuming. In fact it isn’t. Although the angle constantly changes with the form of the hull I found a simple method to get a reasonable fit.

  1. Hold the new strip in place and check the gap along the outer edge of the plank. The bigger the gap the bigger the bevel that needs planing.
  2. Estimate the size of the gap; I used an arbitary scale of zero to three, zero for no gap and three for the big gaps that occur as the planks bend at the soft chines. I marked the numbers on the plank as I worked along it.
  3. Transfer the plank to a vice and start planning the bevel. I did it purely by eye, changing the angle according to the adjacent number and making sure the bevel transitions smoothly along the plank. I found it takes about five minutes to do an eight-foot strip.
  4. Refit and adjust if necessary.

It really is that easy and perfection isn’t necessary as the real strength in the structure will come from the glass cloth. Strips are less fragile and easier to handle this way. I haven’t used bead and cove on this small scale so I can’t comment on overall speed.

These light weight bar-clamps cost just a few bucks and are ideal for holding strips between stations.

These light weight bar-clamps cost just a few bucks and are ideal for holding strips between stations.

My strips were ¼” thick and ¾” wide except those that made a tighter turn at the chines where I used strips a little over ½” wide.

To handle the upswept bow and stern, I cut the strips down the middle, length ways with a utility knife – effectively laminating using narrower strips.

The compound curvature at the stern was challenging but I found that careful use of a heat gun would allow me to set some twist and bend in the strips making the final gluing, clamping and stapling easier.

Staples would secure most strips but I needed clamps at the bow and stern too. I used a maple keel and mahogany sheer strip – great for bracing clamps as red cedar is just too soft for repeated clamping.

Here the clamps are reversed to push against the maple keel.

Here the clamps are reversed to push against the maple keel.

Aligning stations with a simple laser-level is easy.

Aligning stations with a simple laser-level is easy.

A friend introduced me to kayaking last year and quickly got me hooked. I decided to build one over the winter and I will report progress from time-to-time and pass on any useful building tips.

A few trips on local lakes convinced me that I wanted my own kayak and subsequent research revealed that choosing one wasn’t as easy as it first seemed. There are always design compromises and in an ideal world one would have a selection of kayaks and chose according to the whim of the moment or the task in hand. I wanted it all; speed, stability, lightness, durability, seaworthiness and carrying capacity all in the same boat but as with other areas of life, compromises would be needed.

I got off to a false start when I purchased plans for a simple, 16’ stitch and glue design from a well known supplier. I soon realized that I had chosen a design which I would quickly outgrow. Although stable and predictable, it was probably going to be slow, so I set aside the plans and resumed my search, eventually settling on the Storm LT by One Ocean Kayaks. It is narrow (21.5” beam) and has a 16’ 3” L.O.A. with graceful, upswept ends. The Storm LT is actually a smaller version of the designer Vaclav Stejskal’s Cape Ann Storm and should be a good match for my 150 lb weight. For a novice its narrow beam may be a bit of a challenge and I hope that I haven’t bitten off more than I can chew. Fortunately, the designer claims good secondary stability which is comforting for someone who loves being on the water not in it.

The plans and manual for this strip-planked boat were beautifully done and there seems to be a plethora of advice available on-line with step-by-step building photographs and tips. There is also a wealth of hydrodynamic data which instills confidence.

So why build when there are plenty of production boats available, some little more expensive than the cost of materials for this strip-planked design? Well, it quickly became clear that a kayak is a boat that you slip-on and wear. It has to be a good fit, in terms of body weight and size, otherwise performance and comfort will suffer. Production boats are available in limited sizes.

In selecting a custom design, I felt that I could get close to the optimum boat for my weight and build. Not only that, I would have the lightest possible boat – important when loading onto a roof-rack or carrying up a beach. Indeed, the Storm LT should weigh less than a carbon-fiber production boat of similar size. Aesthetically, the strip-plank boat also wins hands-down.

I was once helped build a 36’ strip-cedar catamaran. I haven’t used this technique since and wanted to give it another try.

Building the mould was fairly straight forward, except that the plywood spine, built as a box beam, wasn’t perfectly true. I used an inexpensive laser level to check the alignment against convenient datum lines on the stations and made the appropriate adjustments using wedges and other methods of persuasion. The plans suggest using saw horses to support the mold but I opted for a couple of inexpensive metal stands designed for chop-saws or drill presses. These were “ballasted” with heavy items to keep them firmly in position. Now I have a fair mould.

I’m using ¼” red cedar, sawn from clear 16’ boards. I’m not using bead and cove molding but will use a block plane to fit each strip individually. I am using Titebond Polyurethane glue because the squeeze-out turns to foam, making clean-up really easy.

All well and good in theory but I will let you know how it works in practice. Stay tuned!

 

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Applied as a spray, Pettit claims Zinc Coat Barnacle Barrier will protect propellers from barnacle build-up.

I still haven’t figured out why the bronze propeller on my boat is the first thing to become encrusted with barnacles after a haul-out. After all, the main constituent of bronze is copper, and my Pettit Horizons antifouling is loaded with copper and it does its job very well elsewhere. But propellers are generally left bare, probably because modern ablative coatings wouldn’t last long due to the high velocity flow across the spinning blades.

Strictly speaking, my prop is probably a manganese bronze which really makes it a brass. Are you confused yet? Well, a brass is an alloy primarily between copper and zinc, typically with 60% copper. True bronzes are usually an alloy of copper with silicon or (now less common) tin. Brass is an inexpensive alloy and very easy to cast into intricate shapes. Unfortunately in a marine environment brass is very susceptible to corrosion and that’s one reason why a small amount of manganese is added. The zinc and copper are not a homogenous mix. Zinc rich areas are electropositive relative to the copper rich areas and consequently zinc dissolves from the surface by electrolysis in the zinc rich areas.

If your freshly polished propeller has a blotchy pink appearance than it is likely to have already suffered some “dezincification.” Some of the zinc has gone leaving a weak, spongy copper rich areas. This can eventually lead to structural failure. That’s why propellers should have some form of galvanic protection, typically in the form of a zinc anode attached to the shaft.

Rainbird's propeller shows signs of dezincification.

Rainbird’s propeller shows signs of dezincification.

In spite of these areas being copper rich, they are still prone to marine fouling, which is perplexing. Perhaps copper in antifouling is just more readily available to prevent fouling.

I normally polish the propeller with a fine abrasive and leave it untreated. At a recent haul-out, the boat yard suggested that I try Pettit’s Zinc Coat Barnacle Barrier to prevent barnacles growing on my propeller. This comes in a spray bomb and the instructions recommend 3 coats applied one hour apart. This is easy enough. So why would zinc work as an antifouling? The zinc in my prop obviously doesn’t do the job so why should I expect this to work? Once again, maybe it’s availability, and as the yard pointed out, when was the last time I had seen fouling on a zinc anode?

Time will tell if this is an effective solution and I’ll keep you posted.

 

 

Ready for launch; Rainbird's propeller after three coats of Zinc Coat Barnacle Barrier.

Ready for launch; Rainbird’s propeller after three coats of Zinc Coat Barnacle Barrier.