Oloff and Muir de Wet, two South African brothers, taught themselves welding, CAD programmes, keel casting and so much more en route to building their dream cruising yacht.

Occasionally you have the rare privilege of reading a sentence or two that capture your sentiments much better than you yourself could. There Be No Dragons: How to Cross a Big Ocean in a Small Sailboat by the adventurer, entrepreneur and writer Reese Palley was, for me, a book that contained many of my own thoughts and ideas.

One of the highlights is where Palley warns against being “overly dedicated to comfort”. He urges us to

“break the pattern of thought that says more comfort
means a better life. The good life
has damn-all to do with comfort.
The good life has to do with stretching mind and body…”

Ongemak, the name of our boat, is the Afrikaans word for discomfort. It was also the name of our grandfather’s farm, and from the moment that Muir and I came up with this name, it stuck, it grew, and sometimes became akin to a living force behind the project. It was a name that at once reflected our roots in the platteland (remote country) far from the sea, as well as a sense of adventure and a willingness to sacrifice comfort and comfort zones for new, uncharted horizons.

The beginning

Muir and I had our first serious taste of sailing (albeit not of salt water) about 10 years ago when, together with our friends Tinashe, Elisma and Adolf, we acquired a Miura, a 31ft fin-keeled sailing yacht designed by Oswald Berkemeyer, on the Vaal Dam. An article like this is no place for assigning blame, but it was mostly Hennie Olivier’s fault.

Having returned to South Africa after a year-long transcontinental trip, Muir and I were telling Hennie the story of how we had spent our last evening on the beautiful Dakar Yacht Club balcony enjoying sundowners. Staring out over the boats, we’d already started dreaming of new frontiers. So Hennie immediately got up to fetch his Sailing magazine from the car, and together we started going through the classifieds. He later drove from Bloemfontein to advise us when we bought the Miura.

Having a Miura on the Vaal proved to be perfect for our metamorphosis from land animal to amphibian. The Vaal can occasionally be nasty, but it is mostly friendly, and a Miura is always a very forgiving boat.

But we also learned that owning a boat is about a lot more than sailing. It is a way of life, and being part of a community of often eccentric individuals. It is interacting with nature in the most straightforward way, and (if we are honest) often has a lot more to do with the actual keeping and maintaining of a boat than sailing it. This played a major part in what followed.

Human nature means that we always want more and, sadly, sailing does not cure us of this malady.

Soon I started thinking of improvements to the boat – small ones at first and then increasingly larger ones. It didn’t help that I was busy with a PhD in geometry, because often during my years of study I found that when duty called, some other project promising pleasure started calling like a siren in an even louder voice. So slowly an idea started brewing…

My mother often says that Muir and I are twins born two years apart, and it is true that we share a like-mindedness that is sometimes uncanny. So it came as no surprise that, when we discovered we’d both moved on to a new page in our lives, it was in fact the same page (he was now working in aerospace medicine in the Middle East and I was a lecturer in Pretoria).

This is what our new page said:

it makes no sense to sell the best eight hours of every day. Life is short and the world is big. Let’s move to Cape Town and build a yacht.

So in our late 30s we both quit our jobs. We said goodbye to the office, confident that we would soon master the mystical skills of welding and the wielding of power tools. Success was a given, because when he was seven and I was nine, we built a really nice tree house. We even
had the dog up there.

The design criteria

This is what we wanted:

  • A sloop for extensive cruising for two couples
  • Minimum maintenance and simple systems
  • Energy efficiency and complete solar reliance

We wanted an empty shell so we could design our own interior layout and systems, so we began looking for a ready-made hull and deck. But somehow, even though we looked at quite a few, we were never happy. It eventually dawned on us that what we wanted was something much too specific. We realised that we’d have to build our own boat completely from scratch.

There is a lot of information available on different hull materials – steel, wood, glassfibre, ferrocement – and on the pros and cons of each. Our boat was to be used specifically for cruising and we settled on aluminium as the material of choice for the following reasons:

  • Minimum maintenance: I strongly believe that many boats are designed to look nice at boat shows without taking into account how the boat will have to be maintained for the next 30 years. Modern aluminium yachts are not painted on the topsides or on the inside, and osmosis does not exist.
    Steve and Linda Dashew describe how they used to be full of concern for the boat’s gelcoat when tropical traders came in canoes and dugouts to sell fresh fish, fruit or coconuts. But once they got an aluminium boat, concern melted away, and was replaced with nonchalant chat and friendly barter.
    This is what we wanted: ruggedness on the water – the marine equivalent of a Toyota Hilux (I have never seen a bow fender on an aluminium boat!). Lastly, the hull and deck are welded together, resulting in a very dry boat, which also lowers maintenance.
  • A one-off: while GRP is good for mass production, it takes a lot of work to produce a single hull. Aluminium is perfect for a one-off, especially in our case, where the building and designing took place more or less simultaneously. It is the perfect material if you want to weld on, cut off, repair or adapt parts of your boat in future.
  • Strong: aluminium and steel are the choices for those who want to go to high latitudes where things might go bump in the night. But aluminium is much lighter than steel, so there can be much more weight in the keel for a stiffer, safer boat.
  • PEOPLE LOVE THEM: when we asked the owner of a big aluminium yacht at the Royal Cape Yacht Club whether he would care to show us his beauty, he was most welcoming in an unassuming way.
    We had lots of questions. I saw his two Rocna anchors and asked him if he was happy with them. “Well I should be,” he answered, “I designed them.”

It was Peter Smith, and after this first fortuitous encounter at the club he and Marlyse visited us at home on our project on several occasions with lots of valuable advice. He is not one to overstate or exaggerate, but when asked about materials his answer was simple: no material is perfect, but if he had to get another boat, if would be aluminium.

Peter should know – he has sailed to and explored Antarctica in his own boat more than once.

Welding technique was practised a lot. To check for strength, joints were tested in a vice to see if they could be broken.

MIG (Metal Inert Gas) welding: a wire electrode is fed through a welding gun to create an electric arc which melts the wire and pieces of metal to be joined. At the same time a shielding gas is fed over the arc to protect the weld from contaminants in the air.

The dream starts to become a reality as the first sections of hull are welded together

Drawbacks of aluminium

As Peter said, no material is perfect. The main disadvantage of aluminium is the possibility of galvanic corrosion. This can occur when another metal, like stainless steel, is connected to the hull, especially in a wet environment.

The way to prevent this is through a plastic gasket, special sealant or, even more common these days, by using a non-metallic alternative, for instance a plastic seacock rather than a stainless steel one.

Galvanic corrosion can also occur if there are stray currents flowing through a marina, especially if the underwater paintwork is not in good nick. To prevent this, aluminium boats carry sacrificial anodes on the hull. There should be enough of these and they should be checked and replaced as needed every few years. This is not a problem while cruising and anchoring away from commercial power.

I might mention that I have often heard the story of someone who dropped a metal coin in their aluminium boat, and then discovered it a short while later, just in time, before it has corroded straight through the hull.

I believe it’s total nonsense, or at least one of those urban myths that has become more and more fantastic as it has been retold over the years.

To be sure, we did the following experiment: six glass jars, each with a marine grade aluminium disc at the bottom, were filled, three with salt water and three with fresh water. We left the aluminium bare – as far as I know no one goes to the trouble of painting the insides of aluminium hulls. Into these we put samples of respectively stainless steel, lead and a variety of coins. After six months we examined all the samples, and only where the lead sample lay in salt water on the aluminium disc was there the slightest indication of pitting, less than 0.2mm in depth and diameter.

Herein lies an important lesson, namely that it’s often easier to test the validity of a statement than to go on hearsay or to get confused by contradictory theories found on the internet.
So don’t hold back and be shy – test it, break it, burn it or freeze it – it’s great fun!

Economic sense

Lastly, we should mention something about the price of aluminium compared with other materials. The aluminium plates for our boat cost the equivalent of around £4,460, but to this has to be added the price of lots of consumables, as well as various bits of aluminium profile, so the total cost of the hull and deck was nearly double this amount, roughly £8,900.

It may seem tempting to build a boat out of steel or wood, with the cost of a hull and deck being less than two thirds of this price. But it is important to realise that, compared with the price of the whole project (around £41,600), this saving is less than 10%. To my mind it makes no sense to compromise on the hull material, for this would influence the character and the resale value of the boat for years to come. If money is to be saved, it can be done by having a simpler interior, internal systems, rigging or engine. These can always be upgraded later.

A learning experience

One of the most rewarding aspects of creating your own boat is learning skills you might not have acquired in any other way. Neither of us had ever welded before, so one of the first skills we had to learn was MIG (Metal Inert Gas) welding. For this we contacted the South African Institute of Welding in Johannesburg and organised to go on a week’s course.

The instructors there were surprisingly flexible in realising that, unlike most of their students, we were not seeking any form of certification, but rather a broad introduction to different aspects of welding from which we would be able to proceed through practising at home.

At the end of the week we were tired to the bone, but we were given a good nudge in the right direction, as well as lots of advice on what would and would not work for our ambitious project.

Back in Cape Town we bought a cheap MIG welder (which only pushes the welding wire from the machine’s side) and had the cable shortened (for less friction) instead of buying a more expensive push-pull machine. This worked very well and the wire hardly ever got jammed – probably because the wire used for welding marine-grade aluminium is quite stiff.

Then the fun started. We had lots of offcuts once we started cutting the hull plates, and it was on these we practised. We also watched lots of YouTube videos and then we practised some more.

We cut the welded metal up into strips and broke it in the vice. If it broke on the weld it was bad – if it broke on the heat affected zone next to the weld we were happy. The hierarchy of welds seems to be like this: a bad weld looks good but breaks easily; an average weld looks bad but is difficult to break; a good weld looks good and is difficult to break. I think I can safely say that our boat consists of equal amounts of the last two types!

Another skill was to learn how to use power tools. The wonder of working with aluminium is that common woodworking tools are perfectly sufficient: a circular saw (fitted with a blade for cutting aluminium, available from any hardware shop) goes through a metre of aluminium plate in less than two minutes. An angle grinder or pencil grinder fitted with a carbide tipped blade is perfect for removing the cold start of a welding run, but beware that an electric planer can destroy your project – and you if you’re not careful.

Just remember not to use abrasive discs or sandpaper where you want to weld again later – these will contaminate the area and lead to messy or weakened welds. And don’t forget to wear all that safety gear.

Is that a fair curve? Building boats by eye has never gone out of fashion

A place to build

There are those who believe that if you wish for something really hard, then you can attract it through some mysterious force. I’m not one of those people, but that’s more or less what happened anyway. One lunchtime at work, while gazing through our Sailing magazine, I found a curious advertisement: “Accommodation to let. Large loft on second floor of house in Milnerton, together with garden space suitable for building a yacht.”

This was still a year before we planned to move to Cape Town, but, as luck would have it, my best friend Paul Schutte was in Cape Town while finishing his own boat project. Paul happened to be looking for accommodation and he liked the place so much that he agreed to rent it for himself in the interim.

The owner of the house originally wanted to build his own yacht too, so he’d left space next to the house for his construction site. This is good, because, as with many things in life, you should have an exit strategy. It might be possible to build a boat in an enclosed space, but it’s very difficult to get it out again!

With wooden poles and beams covered with plastic tarpaulin and shade cloth, we built a 12m long lean-to next to the house (MIG welding requires a wind free environment). It was a lovely space so we threw a massive party for all our friends – and if you tell lots of people that you’re going to build a yacht in this big tent, then you have to do it!

  1. 1. Introduction
  2. 2. The cost of building your own aluminium sloop
  3. 3. Completing the project of a lifetime
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