David de Villiers Interview – Aluminum Catamaran Design

We spoke with David de Villiers about catamaran design. David is especially interesting because he is at the forefront of a number of design trends including aluminum construction and the push away from condomarans and towards a focus on lightweight, efficient designs. We talk to him about his famous 62 foot ketch catamaran and his DVD 525 version which is being built all over the world currently. He discuses his time in South Africa under Dudley Dix, his transition to designing in New Zealand, and what he sees as the future for himself and the catamaran design world in general.

Please visit his website ( www.devilliersmarinedesign.co.nz ) for additional information about David and get in touch with him about building an aluminum catamaran.

Can you tell us a little about yourself?

Yes sure. I am from South Africa originally. Whilst in my early teens my father, who was a medical doctor/surgeon, purchased a 42’ GRP hull and deck package. We moved back to Cape Town and I helped with the outfitting of the boat. That was my intro into sailing. Soon I was racing yachts every weekend at the Royal Cape Yacht Club. Whilst pursuing a mech eng degree at the UCT, I started the Westlawn course and then also worked for Dudley Dix in my spare time. (Editor’s Note: We did an interview with Dudley Dix which is available via this link.)

Post uni, I delivered a 55’ steel ketch from Cape Town to Turkey and then ended up working for Jay Benford in the Maryland. After a few years I went back to Cape Town and worked with Angelo Lavranos. Then I got itchy feet and started to build my first original design, a 36’ steel cutter but marriage and kid’s cut that short. So we sold the half finished boat and moved to NZ in 1995. I have run my own design office since 2000.

Are you mostly selling custom designs or stock plans?

Mostly custom designs. Because 99% of my boat designs are constructed in aluminium which is not technically a series production material ie. it does not come out of a mould so most times when stock plans are ordered customers request changes to suit their individual requirements. Sometimes those changes are so extensive that a new custom design evolves.

Can you tell us about your DVD 62 and the 52 and 78 ft sisterships?

DVD 62 Catamaran

62’ Cat: In 2007 I got a call from Richard & Jessica Johnson asking if I could design an aluminum 60’ cat. Their vision was for an ocean cruising Cat in alloy, big enough for family plus expedition charter guests. Richard asked me if I could provide a reference. They lived in Oxford Maryland……and I had worked for Jay Benford in St.Michaels, about 20 miles away. So off they went to talk with Jay and the rest is history.

DVD 62 Under Sail

The resulting 62’ alloy cat was my first Cat design and has proven to be very successful. She has sailed about 90000 nautical miles in ten years under the Johnson’s expert seamanship including 4 Pacific crossings from Panama to NZ and one full circumnavigation. Now the boat is owned by well known Nat Geo polar photographer Paul Nicklen and serves as the platform for Sealegacy which is a marine conservation foundation formed by Paul and his partner Cristina Mittermeier. During most of 2020 the vessel was refitted with a full set of North Sails, additional solar capacity, genset, full new Mastervolt batteries, an extended roof over the aft deck, dive compressor, dedicated media center, 16’ RIB tender with 90hp outboard etc etc.

52ft Aluminium Sailing Catamaran

525 Cat: Sometime during 2015 I got to thinking that a smaller more manageable version of the 62’ cat would be worthwhile and so the 525 Cat was born. Drawing on the experience of designing, building and sailing on the 62’ the smaller version embodies much of the same philosophy that went into the bigger boat. There is still a ketch rig option but many people enquire about a single mast rig.

78’ Cat: The 78’ Aluminum Cat was started for a client from Eastern Europe who eventually decided to purchase a second-hand vessel so as to get onto the water quicker.

55’ Cat: We also have a 55’ Alloy Cat design that was partially completed (metal structure) in Germany and is currently being outfitted by the owner in Switzerland. This boat evolved contrary to my philosophy of keeping things light and simple so it’s not really “presentable” from that point of view.

575 Cat Design

575 Cat: We also have an exciting new 575 cat in the works that will be a culmination of everything we have learnt over the past 10-12 years.

315 Plywood cat

315 Cat: Lastly I have a 31’ ply/epoxy cat half built which is my own boat. But it’s on the back burner as I do not have time to complete the boat. This may well evolve into a retirement project!!

All of the DVDesign Aluminum Cat designs feature the following:

  1. Performance Biased, Go-Anywhere Ocean Cruising
  2. Rugged Aluminium Construction
  3. Unrivalled Safety with 6 Watertight Bulkheads
  4. Engine Rooms separate from Accommodation Spaces
  5. Forward Working Cockpit
  6. Protected Helm Station
  7. Large, Covered Lounging Aft Deck
  8. Compliant with Lloyd’s special Service Craft Rules, plus
    • ISO rules for Buoyancy and Stability
    • ISO rules for Quick-draining Cockpits and Recesses
    • ISO rules for Window, Doors and Hatch Closures
DVD 62 Under Construction

The ketch rig is very unusual.  Can you explain why you chose to design her as a ketch?

As mentioned I worked very closely with the original clients for the 62’ Cat. The rig was intended to fit under the ICW bridges (66’) so a ketch rig seemed the most practical from that point of view. As it turned out the rig grew and so the air draft is now 73’. The ketch rig has the advantage of having smaller sail areas which are easy to manage and a lower centre of effort.

How does designing aluminum catamarans compare to fiberglass?

Designing in Aluminium is very labour intensive at the design stage especially if CNC cutfiles for the entire structure are produced. Typically we are talking between 15 and 25 hours per foot of length to complete an alloy design, including the cutfiles and assemblies (build kit). Sometimes I think I am a sucker for punishment but it’s what I have specialised in and what I am reasonably skilled at!

Who is generally building your designs?  Where in the world?

First of all there was the 62’ Cat built in NZ at Q-West and outfitted by the original owners in Nelson. That boat has gone on to become Sealegacy1. We have sold 3 sets of plans for the 525 Cat so far. Two to Australia, one of which is a self-build started a few months ago by a very capable family and soon a turnkey build will start in Europe at a professional yard. We are also getting close to the 2 new builds in South Africa at the Jacob’s Bro’s yard in Cape Town. As we speak they are erecting a new build facility which will house 2 of the 525 Cats simultaneously.

What do you think is the most important consideration when designing a cruising catamaran?

Keep things simple and do not be tempted into filling the entire internal volume with “stuff”.

The 62’ Cat originally had no genset, no aircon and for example used an Ipad with charts loaded for the first 50000 nautical miles.

What are your thoughts about the current state of design for charter catamarans?

Can I be blunt here? Clearly some of them are exceedingly heavy and many should not be considered proper voyaging boats. Please don’t get me wrong…..some of the recent charter cats are super luxurious and well appointed and there certainly is a place for them in the charter Cat market. But there is one 50 foot cat weighing in at 20 tonnes Lightship which is a tonne more than the equivalent number for my 62 cat design.

Do you have any thoughts on the recent trend towards reverse bows on cruising catamarans?

This is a “contentious” issue. First of all I think trends and fashions have changed and reverse bows look cool. The most important advantage however is that stretching the waterline to it’s maximum has the effect of moving the LCF forward to come closer to or even ahead of the LCG. This reduces pitching as well as increasing the speed potential. So there a lot of people who would advocate for normal raked stems and flared bow sections to keep water off the deck but if the boat is more balanced and pitches less then the flared bows are not really necessary. Having said that we are now starting to pursue asymmetrical bows where the wedge panel (chamber between the inboard hull side and the under wing surfaces) carries all the way forward to the stem and which will further reduce water coming into the forward cockpit.

Reverse bows on DVD 525

How has catamaran design changed over your career?

Even though I started designing in the early 90’s and started my own design office in 2000 my first Cat design….the 62’ was started in 2007. So I have been doing Cat design for a relatively short time……12 years……..even in this time things have changed. Most cats are now “floating condo’s” ….there is a trend towards increasing the WLB to WLL ratio’s and decreasing the bridgedeck clearance which is not comfortable or safe from a voyaging perspective. There’s some cats out there that are almost barges……Even if it means losing a commission I won’t go there.

Good bridgedeck clearance on DVD 62

Where do you see catamaran design going in the next 10 years?

I would hope that the emphasis goes back towards “proper” sailing boats that are seaworthy, simple and relatively quick. I don’t really think the “foiling thing” will cross over into mainstream multihull cruising but I have been wrong many times before!

I would like to think that as sailor’s contemplate cruising to more out of the way places that aluminium construction will become more popular. Most of the people enquiring after my cat designs talk about voyaging long distances efficiently, accommodating fewer people, cruising higher latitudes and more rugged areas (which is really well suited to aluminum boats), having good sun protection over the aft deck area thus maximising the solar capacity. Ikea-style interiors are great at boatshows but not so good over a 5 to 10 year cruising life.

How can people learn more about your catamaran designs and purchase plans from you?

Generally most enquiries come via my website at www.devilliersmarinedesign.co.nz

I also post on my business page on FB quite frequently. No print advertising at present.

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