Re: My son loves his trimaran now its my turn!

Hi Mike

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First, thank you Brian and David for your insights. I appreciate this very much. This is what a forum, group should be about. I as a designer biased of course. I like them all, otherwise, I had not designed them.

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Very short, all boats you are interested in have more or less the same stability characteristic. The sail area should be decreased above 20 knots. I add the ECO 6 stability diagram to see the stability characteristic of this boat.?

As mentioned by Brian. The lower CE of a biplane rig plus the possibility to shorten sail very fast is a big safety factor. It is the quickest way to shorten sails.

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Masts. The windsurf masts for the DUO 480 are a more European solution. Here in France, we get them now in the Winter from Euro 50,- onwards. I admit it is the minimum solution. Brian's masts are the real good solution. Lucky he lives in New Zealand where carbon tubes can be obtained for good prices. I was surfing in Alibaba. Found 80mm diameter carbon tubes for 35,- $ per 1m. So one mast would cost 227,5 $. The bad thing, the transport costs 135 $ to the USA or Europe are the same. Total is 590,- $.? But overall a reasonable price.?

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Building your own boat has many advantages. We have here some very interesting solutions. One of them is the gaff rig from David and the Dyneema rigging. By using an Al tube as a mast. Hu, a gaff rig? where is the difference between the popular fat heat sail and a gaff sail There is none. But the costs for the total rig were kept down without sacrificing sail quality.

Weight, having a light multihull is a safety factor.? The defense is a fast accelerating, principal, running away from the wind and reducing in this way the force of a gust. By the way. If this happens, do not luff up, bear away and loosen the main sheet to lessen the rotational effect.

Construction time is a controversial issue. It is individual.? For example, the beautiful ECO 55 as built in New Zealand by Hamish was taking two years. Martin in Nicaragua built his boat in 600 hours including the Gunter rig ( see some clips in this video:? https://www.youtube.com/watch?v=ioKESt3xtUU. In Russia, the boat was built in 3 weeks by three men. See photos (Economy cruiser pictures). Take your pick!

To stay in the size range. Brian mentioned it already. Look at the?

KD 650.

I hope this helps you a bit to make the right decision for you

Re: My son loves his trimaran now its my turn!

Michael Mitchell

#9086

David,

I know you can't?choose the boat for me. I have 4 sets of plans from Bernd (Tiny Tri (built and given to my grandson) Fun boat., Eco 6, 520 and 480.) I really think I prefer the 480. Did you ever hear of a boat owner wanting a smaller boat??

Thanks for your response.

Mike

Quincy, Fl

Show quoted text

On Mon, Dec 6, 2021 at 11:06 AM David Thatcher <david.thatcher@...> wrote:

Hello Mike,
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I would have thought that the more beam, and heavier the boat, the less resistant to capsize it would be. But in the case of the 480 this is countered by the fact that the boat has a bi-plane rig and therefore the sails are much lower down so therefore less capsize moment. But I think that all three boats would be stable enough so your choice should really center around the boat that best suits your needs in terms of space and accommodation, and also ease of building.
?
In the almost year of sailing my Eco 6 in a range of conditions I have never felt there was a risk of capsize. The boat does heel a bit with the windward partially lifting out of the water, but I am probably more fearful of breaking something than I am of capsize.
?
David

Re: My son loves his trimaran now its my turn!

Michael Mitchell

#9085

I am glad you responded and you have the 480. I have been researching windsurfer masts and have found none tall enough to match the boat's specks. I have found tall enough carbon fiber and aluminum flag poles of the correct diameter (approx) They come in sections and I don't?know if they would be suitable?if epoxied together.. Maybe insert a wooden piece the length of the mast to stiffen it up.

I think the 480?would be the best for me even though it is smaller than the 520..Based on my 23 foot mono hull's useage I probably would use it more. The reason for the capsize question is my wife would not sail on my 23 because it healed too much.

I have considered scaling the 520 rig and using that rig. But not being a structural?engineer?I don't?know if would work.

Again thanks for your information.

Mike

Quincy, Fl

Show quoted text

On Mon, Dec 6, 2021 at 11:05 AM bryanandmarycox <bm.cox@...> wrote:

Hi Michael

the answers to your questions will not, in my opinion, give you a good indication of which will be the best boat for your individual requirements. I will give my opinion on the questions you asked first. Bear in mind I have got the 480 and while I will give you accurate information about that boat only I am not saying it is the best for you

OK, your questions: Stable: the 480 with its low centre of gravity because of the biplane rig. Also if it is rigged like mine the sails can be furled or reefed in a few seconds without letting go of the helm.

Faster: in theory of course the boat with the greatest waterline length should be the fastest. But if the boat is loaded up with cruising equipment and is fitted out with a toilet and galley (kitchen) and there are 3 or 4 people on board, then the biggest boat may not be the fastest. For example if you are doing day sailing and carry only the supplies needed for the day, and if there are only 2 people on board then that boat, whichever model, will possibly be faster. Multihulls get a lot slower when they are heavily loaded as Bernd will tell you.

But look, these questions are only part of what you need to decide. You need to decide if you are going to do extended sailing including summer holidays, not just overnight. If you have got access to a nice place to put the boat on a mooring like David has with his Eco 6, then you can avoid owning a trailer and the associated costs. If you are going to keep the boat on a trailer and launch it every time you sail you would be at an advantage if you dont have to travel too far to launch the boat.
If you are going to launch the boat every time you sail as I do then I guarantee the 480 is far, far quicker to rig. The 520 of course is a new design so we havent seen it yet. But I have been lucky enough to visit David a couple of times when he was building his Eco 6, and also Hamish with his Eco 5.5. They are both beautiful boats and the builders did a great job with them. So I am not reccomending the 480 over these other boats, i really like them all. By the way we also had a KD650 built locally here as well which I sailed on many times and that is a great boat too if you want something a bit bigger.

I hope David may contribute to this discussion and tell you more about the 6. He is also a vey experienced sailor and has published sailing and cruising books so he knows what he is talking about. Any boat with a cabin takes time to build so it also depends on your personal experience. For example David built his 6 quicker than I built the 480.?

regards
Bryan

Re: My son loves his trimaran now its my turn!

#9084

开云体育

Hello Mike,

?

I would have thought that the more beam, and heavier the boat, the less resistant to capsize it would be. But in the case of the 480 this is countered by the fact that the boat has a bi-plane rig and therefore the sails are much lower down so therefore less capsize moment. But I think that all three boats would be stable enough so your choice should really center around the boat that best suits your needs in terms of space and accommodation, and also ease of building.

?

In the almost year of sailing my Eco 6 in a range of conditions I have never felt there was a risk of capsize. The boat does heel a bit with the windward partially lifting out of the water, but I am probably more fearful of breaking something than I am of capsize.

?

David

Re: My son loves his trimaran now its my turn!

#9083

Hi Michael

the answers to your questions will not, in my opinion, give you a good indication of which will be the best boat for your individual requirements. I will give my opinion on the questions you asked first. Bear in mind I have got the 480 and while I will give you accurate information about that boat only I am not saying it is the best for you

OK, your questions: Stable: the 480 with its low centre of gravity because of the biplane rig. Also if it is rigged like mine the sails can be furled or reefed in a few seconds without letting go of the helm.

Faster: in theory of course the boat with the greatest waterline length should be the fastest. But if the boat is loaded up with cruising equipment and is fitted out with a toilet and galley (kitchen) and there are 3 or 4 people on board, then the biggest boat may not be the fastest. For example if you are doing day sailing and carry only the supplies needed for the day, and if there are only 2 people on board then that boat, whichever model, will possibly be faster. Multihulls get a lot slower when they are heavily loaded as Bernd will tell you.

But look, these questions are only part of what you need to decide. You need to decide if you are going to do extended sailing including summer holidays, not just overnight. If you have got access to a nice place to put the boat on a mooring like David has with his Eco 6, then you can avoid owning a trailer and the associated costs. If you are going to keep the boat on a trailer and launch it every time you sail you would be at an advantage if you dont have to travel too far to launch the boat.
If you are going to launch the boat every time you sail as I do then I guarantee the 480 is far, far quicker to rig. The 520 of course is a new design so we havent seen it yet. But I have been lucky enough to visit David a couple of times when he was building his Eco 6, and also Hamish with his Eco 5.5. They are both beautiful boats and the builders did a great job with them. So I am not reccomending the 480 over these other boats, i really like them all. By the way we also had a KD650 built locally here as well which I sailed on many times and that is a great boat too if you want something a bit bigger.

I hope David may contribute to this discussion and tell you more about the 6. He is also a vey experienced sailor and has published sailing and cruising books so he knows what he is talking about. Any boat with a cabin takes time to build so it also depends on your personal experience. For example David built his 6 quicker than I built the 480.?

regards
Bryan

My son loves his trimaran now its my turn!

Michael Mitchell

#9082

But before I do could you tell me which boat is more stable against capsize. Eco 6 or the 520 (while we are at vit the 480) ?
Which boat is the faster?

Explanation: I like the 480 even though it is tiney. I probably would not require it for more than a weekender. I am having problems finding the windsurfer mast(s) of the proper height.
At any rate I will probably settle on the 520. Since I can do my own mast or cut down a used mast.
Here we go!
Mike

Re: 11 photos uploaded #photo-notice

#9081

Hi Zee
Thank you for the update. The devil is always in the detail pieces.
Looking good.

Cheers

Bernd

11 photos uploaded #photo-notice

[email protected] Notification

#9080

The following photos have been uploaded to the DUO 800S Australia album of the [email protected] group.

By: Zee <ratsheldon@...>

Re: Photo 20211123_164336.jpg updated #photo-notice

#9079

Hi Mike
I can not remember sending you a message. Strange and forget it.
But report when this happens again. Then there is something amiss

Cheers

Bernd

Re: Photo 20211123_164336.jpg updated #photo-notice

#9078

I thought not to glue them but to graft them together with the sealant.

Then close with the multilayer giving the oval shape and it fits by itself ...

Or else the 12cm x 2.5cm internal wooden crossbar that goes all the way to the top ...

bye

Re: Photo 20211123_164336.jpg updated #photo-notice

#9076

I was sending you a private mail, concerning your sketch

Bernd

Re: Photo 20211123_164336.jpg updated #photo-notice

#9075

Hi Domenico

Do you know that you can not glue PVC material, besides PVC to PVC?

Use good laminated wood instead.

Cheers

Bernd

Le lundi 29 novembre 2021, 00:33:42 UTC+1, domenicodispaldro@... <domenicodispaldro@...> a écrit :

Insert empty PVC pipes inside, starting from the base with the 120mm, center 100mm and in the end 80mm divided to the length of 13m.

I show you a drawing as I thought of it.

Hello

Base A-frame.jpg

Re: Summer Sailing Coming up in Southern Hemisphere (New Zealand) with my Duo 480 Jigsaw

#9074

Hi Brian

Good to hear that you get the boat out of the "mothballs".
Have nice sails with your DUO 480 and a happy Christmas

Bernd?

Re: Summer Sailing Coming up in Southern Hemisphere (New Zealand) with my Duo 480 Jigsaw

#9073

Hi Brian

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I wish you many beautiful regattas and enjoy the summer ;-)

Bad lockdown, here in Italy we have had some bad times. Now, thanks to vaccination, 85% of the population seems to be holding on.

We hope well for this Christmas.

Good wind

Summer Sailing Coming up in Southern Hemisphere (New Zealand) with my Duo 480 Jigsaw

#9072

Hi all, I have been cleaning the dust off my Duo 480 Jigsaw and getting it all tidied up for summer. I have just been down to get the trailer re licensed and certified for legal road use. I am hoping to get a lot more?sailing done this summer compared to the last couple of years. It is amazing how 3 months of lockdown motivates you. In the photo you can see I removed the masts while I was at the vehicle testing centre. I have a home made mast holder at the back that fits over the rear crossbeam which was removed temporarily too. But the twin masts are easy to manage and dont stick far over the front of the trailer like a single mast does . All in all this boat is an easy to manage unit both on and off the water. More photos and videos are on my photo files on this site, and I made a building blog during construction, but I just thought it would be good to remind prospective builders what a nice boat the Duo 480 is. Of course there are several great designs of Bernd's in this smaller size range so something to suit everyone.

Happy Christmas everyone
Bryan

53453086_10158298580449829_3185052394144661504_n.jpg

Re: KLM Keels - ECO 6

#9071

Hi Rod, I am only three days drive from you.
Here is a link to my pictures of my 5.5 Power Cat. I changed the design from the deck up to accommodate my solar panels as mine is 100% solar electric.?

/g/K-designs-Multihull-Sailboats/album?id=253293

On my You Tube channel I have a lot of minutes showing what stage I am in as a lot is just made up as I went. Note, keep things light as I got carried away with adding features. Here is a link to the first in my build series.

Regards
Phil

Re: Photo 20211123_164336.jpg updated #photo-notice

#9070

Insert empty PVC pipes inside, starting from the base with the 120mm, center 100mm and in the end 80mm divided to the length of 13m.

I show you a drawing as I thought of it.

Hello

Base A-frame.jpg

353 photos uploaded #photo-notice

[email protected] Notification

#9069

The following photos have been uploaded to the ECO 85 Solar Power album of the [email protected] group.

By: nightline@...

Re: Photo 20211123_164336.jpg updated #photo-notice

#9068

Hi Domenico

Good thinking to use composite structure for the A-frame masts. I was contemplating also to goo in this direction.
Because the cross braces are much more say and quick to make and connect to the mast parts. In the end. The mast will be a lot lighter too.

Cheers

Bernd

Re: Photo 20211123_164336.jpg updated #photo-notice

#9067

have no problem finding aluminum tubes in Italy. For the tubes of the Duo 900, two 180mm and two 100mm tubes arrived in 20 days. 6m long pipes with diameter from 60mm to 200mm there are no problems.

We had thought of using 120mm x 5mm tubes by positioning the mast vertically and fixing it with two stays at the stern of the two hulls. We go over 150kg

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Now we are directing a composite structure, putting 120mm PVC pipes inside, closing with 6mm oval shaped marine plywood and then carbon fiber and glass coating.

Hi Bernd