Multihull Structure Thoughts

[luckystrike]

The result is a 23 x about 8.25 foot. The proa weight is 80 lbs. The power is a 4 HP 4 stroke outboard. The fuel efficiency according to Kurt is measured in “years to the gallon.” The Proa does up to 13 knots with 2 crew onboard.

The build is unknown as Kurt does curved plywood or foam glass structures in the size of tri’s mentioned here. Kurt also would have a lot of left over materials from other builds he has done EG 40 foot short handed trimarans etc.
.

I have some information to this build. The Vaka is left over from the original Magic Hempel, a Dragonfly 25 (MK I) which won it's class in the famous Rond Britain Racewas, was imported to the US and crashed during a regatta due to a waterstay failiure. Kurt bought the wreck and rebuilt it with some new and updated ama's. The Ama is a tortured ply / cylinder mould structure that started it's live as a experiment for his building technique.

Have Fun, Michel

 

[ALL AT SEA]

I have some information to this build. The Vaka is left over from the original Magic Hempel, a Dragonfly 25 (MK I) which won it's class in the famous Rond Britain Racewas, was imported to the US and crashed during a regatta due to a waterstay failiure. Kurt bought the wreck and rebuilt it with some new and updated ama's. The Ama is a tortured ply / cylinder mould structure that started it's live as a experiment for his building technique.

Have Fun, Michel

Always wondered what happened to Magic Hempel. Thanks

 

[cando2]

Hi luckystrike. I live in the PNW not far from where Kurt Hughes is and heard a different story direct from Kurt's writings and posts. As you say the sea stay broke and the ama was ruined. Kurt was commissioned by the North American owners to design a new set of amas with higher volume for better performance. I remember him mentioning the distance between the aka and the sea stay at the main hull was not providing enough leverage. Years later I read the owners again commissioned Kurt to design a new set of amas based on what they learned from the first set. I think he stated the first set wasn't built quite right. I don't recall if the latest set was also cylinder molded or possibly strip. The power proa main hull was actually the remaining good ama from the original factory build. Unless a recent purchase, I don't believe Kurt ever owned the vaka.

 

[SolGato]

Thought I would post this design I came across while oldMulti is away and hopefully recovering.

It may have been featured before, although a quick search did not find anything.

I happened upon it while looking for vessels powered by larger Torqeedo motors as I have recently been gifted a pair that I intend to use on my 30’ Solar Electric Cat build.

If a pair of 10kW motors did the job moving this thing around, I don’t think I’ll have a any problem with them on mine.

The following info comes from a sale listing that lists the boat as an Oram 62:

"Wabi Sabi" is an innovative 62' Power Cat with electric
drives, 20 Kw lithium batteries, 6 x 130 watt Solar Panels with deck
space for many more and when you fit a 4 kva x 48V diesel generator
you will have unlimited range. There is space on the roof and sides
for another 3.2 kW of solar.

Built in Duflex/Epoxy for lightweight strength, this vessel is a going concern "as is" but there is some finishing work yet to be done.The slim long wave piercing hulls are
easily driven by the silent twin electric Torquedo motors.

The owner's island bed Queen Cabin in the bow of the central hull is extremely
spacious, all it needs is for the walls to be lined.The saloon and
galley again are spacious with a temporary galley installed for
current live aboard use.There is a spacious two pack painted bathroom
at saloon level.The cockpit in the aft third of the main hull has
doors to port and starboard for access to the hulls and has ample
space for relaxing / entertaining at anchor.There is additional
sleeping for two in each outer hull and a laundry in the starboard
hull.

And from Ecoboats.com.au:

Gold Coast resident Horst has a long history of designing and building radical multihulls and his latest creation is a grand vision. At 62 foot it is a very sleek machine and a suspended pod between the hulls offers a protected cockpit and a surprisingly spacious and homely living area. Horst has been closely involved with the design & construction of the craft and given it’s so easily driven thanks to it’s efficient hull shape, it’s a perfect type of craft for electric propulsion. A set-up of two Torqeedo Cruise 10.0RXL electric outboards gives the boat an overall performance that is comparable to having a total of 40 to 50hp (in terms of speed & thrust). A Lithium battery bank of 20kW with scope to add more capacity in the future) can be re-charged from either marina power or from solar panels on the roof of the boat when it’s underway or at anchor.

 

[Russell Brown]

It looks a bit like my much smaller power-cat.

 

[SolGato]

It looks a bit like my much smaller power-cat.

Absolutely!

They would make a fine pair with yours serving as a tender/runabout as I can’t imagine it’s easy finding parking for a 62’ boat when you want to grab a bite or supplies.
.

 

[ALL AT SEA]

Thought I would post this design I came across while oldMulti is away and hopefully recovering.

It may have been featured before, although a quick search did not find anything.

I happened upon it while looking for vessels powered by larger Torqeedo motors as I have recently been gifted a pair that I intend to use on my 30’ Solar Electric Cat build.

If a pair of 10kW motors did the job moving this thing around, I don’t think I’ll have a any problem with them on mine.

The following info comes from a sale listing that lists the boat as an Oram 62:

"Wabi Sabi" is an innovative 62' Power Cat with electric
drives, 20 Kw lithium batteries, 6 x 130 watt Solar Panels with deck
space for many more and when you fit a 4 kva x 48V diesel generator
you will have unlimited range. There is space on the roof and sides
for another 3.2 kW of solar.

Built in Duflex/Epoxy for lightweight strength, this vessel is a going concern "as is" but there is some finishing work yet to be done.The slim long wave piercing hulls are
easily driven by the silent twin electric Torquedo motors.

The owner's island bed Queen Cabin in the bow of the central hull is extremely
spacious, all it needs is for the walls to be lined.The saloon and
galley again are spacious with a temporary galley installed for
current live aboard use.There is a spacious two pack painted bathroom
at saloon level.The cockpit in the aft third of the main hull has
doors to port and starboard for access to the hulls and has ample
space for relaxing / entertaining at anchor.There is additional
sleeping for two in each outer hull and a laundry in the starboard
hull.

And from Ecoboats.com.au:

Gold Coast resident Horst has a long history of designing and building radical multihulls and his latest creation is a grand vision. At 62 foot it is a very sleek machine and a suspended pod between the hulls offers a protected cockpit and a surprisingly spacious and homely living area. Horst has been closely involved with the design & construction of the craft and given it’s so easily driven thanks to it’s efficient hull shape, it’s a perfect type of craft for electric propulsion. A set-up of two Torqeedo Cruise 10.0RXL electric outboards gives the boat an overall performance that is comparable to having a total of 40 to 50hp (in terms of speed & thrust). A Lithium battery bank of 20kW with scope to add more capacity in the future) can be re-charged from either marina power or from solar panels on the roof of the boat when it’s underway or at anchor.

I'm likely wrong, but she looks like an Oram pod Cat that was designed with a freestanding unarig then converted to (electric)power after the structure didn't cope with the loads generated by the rig...

 

[rob denney]

I'm likely wrong, but she looks like an Oram pod Cat that was designed with a freestanding unarig then converted to (electric)power after the structure didn't cope with the loads generated by the rig...

Correct, but it never got a mast. One of my proas was stored under the boat for a year or so and I got to know Horst when I delivered the rent (carton of booze) each week. We discussed masts and he was going to build one (or two), but decided electric was the way to go. The 2 x Torqeedos were fine for cruising round the Gold Coast, maybe not for a trip to Thailand, which was the intention. I was also peripherally involved with the battery and control system, which is top notch, the same as on Ocean Crusader-J Bird, the only electric powered boat to sail in the Sydney Hobart. It would be a fun boat to own, if length is not an issue.

 

[bajansailor]

Here is a thread on the YBW Forum in England, looking for advice re what cat to buy.
In it, a question is asked as to what make of cat the one in the photo below is - @oldmulti do you recognise her?
What catamaran should we buy? https://forums.ybw.com/threads/what-catamaran-should-we-buy.617071/page-2#post-8619085

 

[oldmulti]

Bajansailor. Sorry, I do not recognise this design. Gabart part owns a company that does design and development of various cat, tri and foiling designs so to do a bespoke design to suit his needs would not be hard, especially with his sailing back ground. This cat looks about 60 foot which is half the size of the tri he sailed around the world. I hope someone who is closer to him can tell us more. One eye fixed next eye in 2 weeks.

 

[yabots]

Fascinating construction — light, strong, and seems easy to maintain. Do you know if the aluminum space frame caused any issues with bonding or movement over time?

 

[Russell Brown]

Bajansailor. Sorry, I do not recognise this design. Gabart part owns a company that does design and development of various cat, tri and foiling designs so to do a bespoke design to suit his needs would not be hard, especially with his sailing back ground. This cat looks about 60 foot which is half the size of the tri he sailed around the world. I hope someone who is closer to him can tell us more. One eye fixed next eye in 2 weeks.

Glad you seem to be getting through the eye operations.

 

[ALL AT SEA]

Correct, but it never got a mast. One of my proas was stored under the boat for a year or so and I got to know Horst when I delivered the rent (carton of booze) each week. We discussed masts and he was going to build one (or two), but decided electric was the way to go. The 2 x Torqeedos were fine for cruising round the Gold Coast, maybe not for a trip to Thailand, which was the intention. I was also peripherally involved with the battery and control system, which is top notch, the same as on Ocean Crusader-J Bird, the only electric powered boat to sail in the Sydney Hobart. It would be a fun boat to own, if length is not an issue.

I know at least one of those Orams was built with a unarig. It was a great concept, does anyone know what happened to it?

 

[Burger]

I know at least one of those Orams was built with a unarig. It was a great concept, does anyone know what happened to it?

There was one built in Airlie Beach by Horst and Ian, for a client.
I used to pop in frequently to watch the then-new Duflex build, amazingly fast.
Trucking the big beast to the launch site was a helluva job.
The owner had her on the market several years ago, back injury meant he couldn't use it. Don't know if it sold.

 

[TrimaranMan]

I have posted here before about my Kelsall trimaran in the Multihull Structure thoughts thread which is one of the best multihull history resources I have ever found. Now I have created a website for the boat. This is not commercial or selling anything just information that others may find interesting particularly the history and different evolution of designs. I have been collecting magazines and pictures and online material for the last 50 years so I wanted to try and put some of what I have in shareable resource. It is just an early version now with pages about my boat and the rebuild. Then I have done a biographical section on Derek Kelsall with pages on his different designs and separate sections on for example the Nick Keig boats and the Great Britain trimarans. I have started a separate section on multihull pioneers with some early designers/sailors. I did a lot on Wharram and the other designers I will expand.

The site is at: www.trilogy-sailing.co.uk

It is a work in progress and I will be editing and adding, correcting and generally working on it whenever I have time. Anyone who has stories to tell about the designers I have mentioned or others and data, pictures and drawings plus corrections of my mistake I would be happy to hear from via this thread or via my website. I hope others will enjoy reading what is up so far and as I develop the site further. I cannot stress more that this is a site intended for those who like multihulls and their history to enjoy rather as Old Multi does with his thread on this wonderful forum which is a treasure chest in my opinion!