Re: Photo IMG-20211231-WA0009.jpeg updated #photo-notice

Thanks for another impressive photo.?
The solar panel roof will be mounted lower in the end, or?

Cheers

Bernd

Re: Added album Eco 6 The first year of sailing. #photo-notice

Beautiful David. Thanks for posting and it looks like you had a great trip

cheers, Bryan

Added album Eco 6 The first year of sailing. #photo-notice

[email protected] Notification

David Thatcher <david.thatcher@...> added the album Eco 6 The first year of sailing.: Most of the photo albums on this group are of boat construction. But what about after the boat is built? Here are some photos of our first year of sailing our little Eco 6 catamaran which included a recent 3 week extended coastal cruise.

Photo IMG-20211231-WA0009.jpeg updated #photo-notice

[email protected] Notification

#9184

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

IMG-20211231-WA0009.jpeg

By: nightline@...

10 photos uploaded #photo-notice

[email protected] Notification

#9183

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

By: Zee <ratsheldon@...>

Re: Trailer for Eco 5

#9182

I think I've found a suitable trailer, though I may have to have it customized a bit, as Bryan (thanks!) has described.

Jim

Re: DUO for South East Asia

#9181

Bernd,

I will continue to discuss with you through email regarding this project.

I sent you an email to bernd@.... Please let me know if you prefer me to send to another mailbox.

Alain

Re: DUO for South East Asia

#9180

Alain
I have no problem adding an open bridge version to the KD 860 range.

Why do you want the centerboard? The anti-vortex panels do their work. They did not work properly on the Oryx, because they were in the wrong place and too small. He did not consult me. I like his changes otherwise. I am no fan of the split rig's. The idea is good, but the fore wing idea like Flettner used and all Junkers aircraft and which are used on stol aircraft work on aircraft. The speed range is different. We do not start talking about Reynolds numbers on sails. If they have some effects, the effect is too low for the extra work and costs. Same for the wing sails on the Tiki. The only good semi wing which worked and was worth the effort and costs were on the junk from a friend. In principle was it a symmetrical wing section and a long flap. Made from cheap PVC tubes. Not too many trailing edge ropes, so no rope salad as usual.

I am always in favor of a clean and effective rig. So the rotating mast (rig) is the logical choice. What you are talking about wearing? The big grafit/Epoxy bearings on the deck give never a problem. What water? If there are some trips, the is no problem. Brian will you enlighten us, please?

Cheers

Bernd

?

But again. Let’s do this as private emails.

?

Cheers

Bernd

Kensboat.jpg

Re: DUO for South East Asia

#9179

On Sun, Jan 16, 2022 at 02:51 AM, Alain Dupuis wrote:

The rig on the DUO800S is nice however I am a bit worried regarding those rotating masts with potential wear and water infiltration. I would rather consider a static mast. I had a look a the rig you did on the DUO 1000 which is rather puzzling me regarding how it works.

Now the question is: how much would you like to charge to design a KD860 Open?

Please note that time constraint is not an issue as I will most probably start the build sometime in 2023.

I would be really interested to work on the CAD model. I have a good background in Industrial Design and mechanical engineering. I have been a user of Rhino3D for 25 years and I own a full?v.7 license. If that can be of any help.

I look forward talking with you regarding the details of this project.

Re: Duo 900 Italy

#9178

hi Domenico

I have no clue what you are talking about. I do not know this sketch eider.

By the way, I prefer to discuss such details in private emails. No WhatsApp also, because it is too complicated to exchange technical drawings.
I have sent you per email the P 95 fore beam. Regarding the four photos. I think that these could be made a lot lighter. Again, see the drawing I have sent

Chiao

Re: DUO for South East Asia

#9177

Hi Bernd,

That would be fantastic!?

I really love the KD860! An open deck version would be awesome. That would meet my need perfectly.

That would be a great cat for the tropics. i am sure a lot of couples would enjoy having comfortable accommodation for only 2 for romantic trips and lot of outdoor space to entertain. That would also make a great resort dayboat with one hull dedicated to the galley to prepare meals and drinks for guests and one hull dedicated to a very comfortable head.

Your favorite option for the KD860 is the centerboard and I would want that too with auto lift in case it crashes into something. The cat could be beached without any worry. Safety is very high on my list.

The KD860 has also proven to work very well with a parallel rig. The junk rig done by Pete Hill on Oryx is very interesting while I am not too keen on the other modifications he has done to your original design though. When it comes to parallel rigs, one of my favorite design is the one done by Bernard Fercot on Pha, a James Wharram Designs Tiki30. Those are pictures of the two:

The rig on the DUO800S is nice however I am a bit worried regarding those rotating masts with potential wear and water infiltration. I would rather consider a static mast. I had a look a the rig you did on the DUO 1000 which is rather puzzling me regarding how it works.

Now the question is: how much would you like to charge to design a KD860 Open?

Please note that time constraint is not an issue as I will most probably start the build sometime in 2023.

I would be really interested to work on the CAD model. I have a good background in Industrial Design and mechanical engineering. I have been a user of Rhino3D for 25 years and I own a full?v.7 license. If that can be of any help.

I look forward talking with you regarding the details of this project.

Re: DUO for South East Asia

#9176

开云体育

Bernd is entirely correct in saying that any shadow across a solar panel will have the effect of reducing the output, so for this reason mounting a solar panel on a yacht is always about finding the best compromise. Solar panels work best when they are orientated towards the sun, but that is not practical on a boat which is always moving around, so it is best for the panels to be mounted horizontally. There is so much cabin top space on a bridge deck catamaran that the cabin top is the logical place to mount solar panels, so as already stated I have my two panels permanently mounted on the cabin top, aft on one side, and forward on the other side. The reason for mounting one forward and one aft is to try and ensure that at least one panel will not be in shadow at any time.

?

Remember that solar panels never put out what they are rated for. Between my two 60 watt panels I should get 10 amps plus, but the most I have seen going into may battery is just under 6 amps, but most of the time it is between 3 and 4 amps. A good MPPT controller will boost the amount of power going into the battery over what is produced by the panels.

?

Probably the best place to mount solar panels on a yacht is at the stern where they will be least affected by shadows from the sails and rigging. The trouble is that there are so many ugly and heavy metal solar panel mounts put on the stern of many yachts. I have a friend who owns an 11 meter performance catamaran. He constructed a very nice composite dinghy davits at the stern of his boat and incorporated a 200 watt solar panel.

?

The other thing about using solar panels and a wind generator is to minimise the yachts electrical needs, because what is taken out of the battery each day needs to be put back in again. Our fridge is rated at an average power consumption of 13 watts, LED lights do not use much power, nor does charging phones and other electronic equipment, all of which is done through USB chargers. Our Tillerpilot uses the most power at over 1 amp per hour, and the small chart plotter probably uses about 1 amp per hour, but I do not switch it on very often, only when I am in a navigation critical situation, but I also often use Navionics on my phone for speed monitoring and navigation, it is actually better than the chart plotter I have.

?

Wind generators are things that a lot of people hate. I had good success with a Rutland 914i generator on a previous yacht. The output is not high, but it just spins? away all the time putting in a constant trickle charge, and it was very quiet. When combined with solar panels it met all the charging needs of our cruising yacht, but once again we minimised our electrical needs.

?

David

Re: Duo 900 Italy

#9175

Hi Bernd

I am at home and the workshop is located a few kilometers from my home.

Until the end of January I will work on the Duo 900 to finish the work on the pipes and the central column that goes from the stern tube, through the central tube and forward.

As we agreed, the central beam in 8mm okume 'plywood and holes 185mm in diameter will be built, for the passage of 180mm pipes. It will also be easy to assemble the base of the mast, since there will be a counter plate underneath with 4 240mm bolts, the one below will have a 60mm x 600mm tube, with a stainless steel cable attachment for the weight of the mast.

As per drawing it will look like this.

Bye

Colonna.jpg

Re: Duo 900 Italy

#9174

So you are back. Looks very good.?
Is the workshop in the same place?

Bye

Re: DUO for South East Asia

#9173

Alain

I projected what you want in the KD 860. It is what you have sketched.?
There is no problem to re-design the KD 860 in this direction. Not much work also.
The boat has also a good volume towards the transom to handle the structure and weight of?

solar panels.

Cheers

Bernd

KD860openbridge.dxf

KD860openbridge.jpg

Re: DUO for South East Asia

#9172

Hi Bernd,

Thank you very much your insights.

In fact, what would be great for my needs would be a DUO900S in the same way you did a DUO800S from the original DUO800.

This is a quick sketch of my ideas.

Could the original design for the DUO900 be modified easily to achieve this? I would imagine that the most work would be to define the new sail plan for a parallel rig (junk/wingsail/wishbone).

Re: DUO for South East Asia

#9171

Hi David Thatcher I wanted to ask you for advice on solar panels.

I also thought of putting two solar panels on the boat entrance doors with measures 70x100cm.

Looking at the photo, I think it is the best place to put the two panels, but Bernd says that a cable passing over a photovoltaic panel decreases the charging yield.

Reading your message, I see that you had no problems and were satisfied with your photovoltaic system and I think that the DUO 900 system is the same as your boat, as there are two small cabins.

In my area many have advised me to put a 600w wind turbine. As you can see, I am undecided on what to use between photovoltaic and turbine.

Bye

DUO900.jpg

Re: DUO for South East Asia

#9170

开云体育

On the subject of solar panels I have found them to be very effective at supplying all of our battery charging needs. On our little Eco 6 catamaran I have two 60watt panels permanently fitted to the cabin top, one either side. These charge a 100ah Lithium Phosphate battery through an MPPT Charge Controller. Our electrics are simple; an 18 liter Waeco refrigerator, some interior LED lights, LED nav lights, USB charging points, and a Tillerpilot.? My wife and I have just been away cruising for 3 weeks on this boat and we found our battery reached fully charged by early afternoon each day. I do carry a spare flexible 50 watt solar panel as a backup, but so far have not needed it. ?To be fair I must say that we have very high levels of UV in New Zealand.

?

My previous 10m monohull cruising yacht had an outboard for the engine so on that boat we were also reliant on solar panels and a small wind generator for all of our electrical energy needs, and once again we never had any problems keeping our battery charged up, and this also included running an electric fridge. It is important to allow the solar panels to have as much direct sun as possible and yes, it is important that they are not obscured. Even when cruising fulltime offshore on the 10 meter boat we found the solar panels and wind generator supplied enough charging for all of our needs, and even at night when passage making the little wind generator just whirling away kept our battery over 13 volts.

?

David

Re: Duo 900 Italy

#9169

Hello to all,?
I'm working on the Duo 900 and from the last photos I finished the tube work.
Bye

IMG-20220114-WA0000.jpg

IMG-20220114-WA0002.jpg

IMG-20220114-WA0003.jpg

IMG-20220114-WA0001.jpg

Re: DUO for South East Asia

#9168

Thanks from me also for this information Bernd. It answers my question about using a dual mast rig on the DUO 900. And I appreciate your insight into the solar panels. In my opinion, still need two panels (for electricity at mooring) but I understand 100% about their efficiency reduction with even the smallest obstacle.?