DIY Boatbuilding. Building ‘Ongemak’. Part 3

The day we had been waiting for since the thought of building ‘Ongemak’ was germinated.

Part 3 of 3 parts

by Oloff de Wet

Brothers Oloff and Muir de Wet recently launched their aluminium sloop, ‘Ongemak’, which they built over a period of five years. This is part 1 of their nautical adventure in their backyard which offers some very sage advice to anyone contemplating a self-build sailing yacht project.

This evening we sit in Hout Bay Yacht Club, having brought ‘Ongemak’ round from Cape Town. The forecast warned of heavy weather in the evening, but we and the other boats which were out, were quite surprised when, in a matter of minutes, the balmy afternoon’s 10 knots became 30 knots. We were forced to put in two reefs very quickly, and by the time we reached Hout Bay it was approaching 40 knots. Something like this is obviously not a pleasant surprise, but it was pleasing to realise that the boat always felt safe and handled herself well. Right now it is raining and blowing at 50 knots! But fortunately I am looking out at this forceful display of nature over the bay, from the safety of the clubhouse, with a beer in my hand.

She’s in!

To Build or not to Build
To be in a boat, and to sail it, while always being aware of the fact that you created it yourself, are some of the most rewarding experiences I have ever had. I believe that to experience and to create are two of the most important things that this world has to offer. Some other advantages of building are:

1. You acquire many new skills, like designing, welding, carpentry, and, very importantly, how to negotiate with chandlers.

2. You get exactly what you want. From the length of the bunks to the make of the foot-pumps, it is all for you to decide.

3. You know your boat inside out. If there is ever a problem with the plumbing or the electricity, you will be able to find the fault and to repair it quicker than any professional.

4. While doing all this you visit strange places and meet interesting people – I often had the feeling of being a tourist in my own city.

5. Your whole tribe eventually gets involved. Friends, neighbours and family get inspired by the idea that one can do something totally out of the box, and often someone would quickly come by just for a short chat and to see how things are going, or give you something they found in the garage which might help you in your project.

But there are disadvantages as well to building your own boat. Two main ones come to mind:

Stepping the mast.

6. Time: Muir and I both did some part-time work and spent some time fixing up and managing our rental properties. But for about eight months of every year we worked nearly exclusively on the boat. I estimate that we each worked about 1000 hours a year on the boat for 5 years. Of course about half the time was spent designing and planning, and I am sure that to make another boat will take less than half the time, but anyone building should keep in mind that every single job usually takes longer than what one estimates. It is not for no reason that there are so many semi-complete boats all over the country.

7. Money: Building one’s own boat is not a cheap way to get a boat. Much rather then buy a good second hand boat and fix it up. But one does end up with a new boat, hopefully at quite a bit less than what a new boat would cost, with the added benefit that costs are spread out over years. Just never, ever, try to think what your time was worth! Rather try to convince yourself that you went to a boat building university, where you did a degree in boat building for free – you just had to supply your own material!

Ultimately, the decision on whether to build or not to build comes down to this: Build a boat because you want to build a boat, not because you simply want a boat.

Working on the interior.

Planning the Interior
The great advantage of getting exactly the boat that you want, can only be realised through proper planning. We looked at many, many boats, in real life and on the web. So much has been done before, so learn to understand what Picasso meant by “good artists copy; great artists steal.” Always have a measuring tape at hand; measure the heights of seats that you like; measure the width of the bathroom door on the aeroplane. When things got critical, we built parts of the interior of cardboard. The most important thing, I believe, is to keep things as straightforward and simple as possible. Rather have good geometry solve the problem, than lots of moving parts.

Many small decisions had to be made, but for the sake of brevity, I list the main features:
8. Wide companion way steps that one can walk up or down with, drink in hand. The top step is deep enough to sit on during watch keeping.

9. Comfortable aft cabin with athwartship double bed.

The interior beginning to take shape.

10. Heads aft with full-size toilet.

11. Large G-shaped galley with the engine under the counter and accessible from all sides.

12. Saloon benches and saloon sole are all long enough to sleep on.

13. Comfortable forecabin with watertight impact compartment and large stowage.

14. Deep anchor locker keeps the weight of the 50m chain low.

15. Clear forward view from the saloon.

Fine details being attended to.

Building the Interior
The interior consists of many small diverse jobs, so it is never boring and generally you have to move on to the next phase just when you were comfortable with what you were doing.

Carpentry on ‘Ongemak’ was fairly basic, and a lot consisted of bolting marine plywood to the frames and stringers which were already in place. This process is very quick and the result is extremely strong. We had all the ply for the bulkheads professionally covered with Formica on both sides. Formica is usually used for kitchen counters, so on bulkheads it will hopefully last forever without any maintenance. Most of the cabinets got the same Formica finish, but we made liberal use of Burmese teak for trimming and for fiddle rails. Hennie Olivier gave us this rare gift, wood off a 1918 railway coach which he saved after having done the whole of the interior of his beautiful Miura, Sieraad. Personally I love this contrast in our boat between the new modern materials and the age old teak.

A big part of the interior is plumbing and electricity. There is a lot of literature on both, so let me simply note that it is important to use very high quality parts in the hostile marine environment, like proper hose and tin coated wire. We did however find that it is not always necessary to pay an arm and a leg for the marine stamp on a piece of equipment and that bits from your local hardware store can sometimes do the trick. But buy a sacrificial sample in such a case, and test it severely before you allow it on board!

The End – or is it the Beginning
Five years after we started our project, we had our final boat party. There were nearly fifty people, and Muir and I would really like to thank all our friends who lived this dream with us through their constant support and encouragement. A variation on the old toast is in order, I suppose: “To the wind that blows, the ship that goes, and those who love a sailor!”

But a few days later the enormous crane and truck came to transport ‘Ongemak’ to the Royal Cape Yacht Club, and for this occasion we did not invite anyone. It was a private affair – full of excitement, but also stressful with lots of detail to keep in mind. Fortunately, even though there was a strong breeze and a bit of rain, everything went very smoothly. Isolde de Villiers put a lovely video clip of the event on YouTube – search for “Aluminium Zeppelin.” There is also one of the actual launch – “‘Ongemak’ Launch.”

And this then is the end of this story. But a boat which floats is always the beginning of a new story…

Anyone interested in building a yacht at home, or our design in particular, is welcome to contact us at or We are making both the CAD files and the cradle to build the boat in, available for free.

Main Specifications
Design: ‘Ongemak’ 35
LOA: 10,45 m
LOD: 9,90 m
Beam: 3,33 m
Draught: 1,75 m
Displacement: 5,3 tons
Ballast: 2,1 tons
Rig: sloop
Year launched: 2016
Building time: 5 000 hours
Building cost: R650 000

PART 1 of this feature can be read HERE

PART 2 of this feature can be read HERE

View a Video Clip of ‘Ongemak’ HERE

Check Also

“Talking Sailing” From My Archives. 1985 Vasco Photo-Finish

by Richard Crockett It’s rare that one sees a photo-finish in a coastal ocean race, …