Building a 46ft performance/cruising Catamaran

Wild Dog Adventure Riding

Help Support Wild Dog Adventure Riding:

Slainte Mhaith

Bachelor Dog
Joined
Aug 8, 2007
Messages
12,361
Reaction score
671
Location
Pretoria East
Bike
NER-A-CAR
Test fitting the dummy board (real foils will be made from carbon fibre).

Making sure of the correct position before cutting holes in the hull and and laminati g the cases.

That photo looks all sleek and performance, awesome.
 

Takashi

Race Dog
Joined
Mar 14, 2011
Messages
1,899
Reaction score
17
Location
Centurion
Bike
BMW R1200GS Adventure
I would guess they are planning on having lets say 4 strings of 750W each 3kW in total.

You have some shaded spots on one string you lose effectivity on only that string and not the whole system.
Eish. 🤔 Short but loaded sentence there. Can cause expectations which are not met.

If you have significant shade on a part of a panel the diodes can bypass that section and nothing an mppt can do to recover the loss.
The mppt will use to remainder of the output wisely or at max efficiency.

PS With masts and stuff you are going to have constant shades on panels thus make sure the supplier don't blame future panel failures on shading issues (diodes sometimes fail). They must approve the application.
 

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
I would guess they are planning on having lets say 4 strings of 750W each 3kW in total.

You have some shaded spots on one string you lose effectivity on only that string and not the whole system.
That's what I meant, thanks
 

Slainte Mhaith

Bachelor Dog
Joined
Aug 8, 2007
Messages
12,361
Reaction score
671
Location
Pretoria East
Bike
NER-A-CAR
I would guess they are planning on having lets say 4 strings of 750W each 3kW in total.

You have some shaded spots on one string you lose effectivity on only that string and not the whole system.

Thanks, get it now. The statement made it sound that using MPPT chargers will make things better but actually it is the number of strings (and thus more mppts) that make it better.
 

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
Received a few packages this morning...
2 electric motors and 6 lithium batteries and a 5000w inverter/charger.

Getting real now.
 

Attachments

  • LFP-24V-web.png
    LFP-24V-web.png
    290.2 KB · Views: 0
  • 20220710_140129.jpg
    20220710_140129.jpg
    88.5 KB · Views: 0
  • 20220710_140213.jpg
    20220710_140213.jpg
    129.1 KB · Views: 0
  • Screenshot_20220711-103202_Chrome.jpg
    Screenshot_20220711-103202_Chrome.jpg
    37.9 KB · Views: 0

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
So our "composting" heads arrived from OGO today.


No stinky marine heads with their associated blacktanks and raw sewage on this boat. We decided to go with these units from OGO. The only other competition was from a company called Compoost in the UK.

In the end the footprint of the OGO was a much better fit.
 

Attachments

  • IMG-20220729-WA0003.jpeg
    IMG-20220729-WA0003.jpeg
    115.8 KB · Views: 0

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
The spider frame mould is being readied for the lamination process where carbon fibre will be used to save weight.

All interior bulkheads have been laminated and the guys are busy gelcoating all interior surfaces. We are not using any paneling, again to save weight, but also much easier to keep clean.

The aft cockpit piece is ready to be lifted onto the boat.
 

Attachments

  • 20220722_153203.jpg
    20220722_153203.jpg
    357.1 KB · Views: 0
  • 20220729_210453.jpg
    20220729_210453.jpg
    916.3 KB · Views: 0
  • 20220722_153149.jpg
    20220722_153149.jpg
    279.2 KB · Views: 0
  • 20220729_210237.jpg
    20220729_210237.jpg
    248.5 KB · Views: 0

NoRush

Pack Dog
Joined
May 18, 2014
Messages
385
Reaction score
1
Location
Richards Bay
Bike
Yamaha Super Tenere
Permission to aboard Captain ? I do love water but in my swimming pool and love
stable ground. Your thread has just ignited my own dreams I thought was long dead. I will be following this epic build.
 

whitedelight

Grey Hound
Joined
Oct 27, 2008
Messages
5,580
Reaction score
21
Location
Cape Town
Bike
KTM 990 Adventure
Interesting build. Looks similar to a HH catamaran. I really like the aggressive hull design. Is there enough strength in the design to fly a hull?
 

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
Interesting build. Looks similar to a HH catamaran. I really like the aggressive hull design. Is there enough strength in the design to fly a hull?
She is going to be very stiff, carbon fibre stringers across the hull deck. Whether one really want to fly a hull is a completely different question, hahaaa.


The leeward foil will counteract any hull lifting on the windward side by lifting the leeward hull some.
 

whitedelight

Grey Hound
Joined
Oct 27, 2008
Messages
5,580
Reaction score
21
Location
Cape Town
Bike
KTM 990 Adventure
Awesome . That frontend looks so mean. Probably posted before but what is the beam?
 

silberfuchs

Pack Dog
Joined
Sep 16, 2013
Messages
205
Reaction score
4
Bike
KTM 950 SE
Once more I am impressed with your project.
I hope everythings works as you intended to.

My stupid question today is: Why does the design have inverted bows?

Greetings, G.
 

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
Once more I am impressed with your project.
I hope everythings works as you intended to.

My stupid question today is: Why does the design have inverted bows?

Greetings, G.
Very good question actually.

I also asked the builder this question. The main function of reverse bows/wave piercing bows is to reduce pitching. Not only is it uncomfortable but it also negatively affects the performance of the sails.

There is also less deceleration as the bows "slice" through the water.

Disadvantages are that it is more difficult to fend off the bows in tight marina spaces, there is a risk of stuffing the bow (on this boat we have curved lifting foils that reduces that problem) and less volume in sail lockers up front.

So in summary it has everything to do with increasing sailing performance. I'm not complaining about the looks either!
 

Ratel

Race Dog
Joined
Jan 29, 2007
Messages
1,987
Reaction score
44
Location
Dubai - UAE
Bike
KTM 990 Adventure
Awesome . That frontend looks so mean. Probably posted before but what is the beam?
The beam is 7.5 meters.



 

roxenz

Grey Hound
WD Supporter
Joined
Sep 16, 2008
Messages
5,988
Reaction score
328
Location
West Rand
Bike
Yamaha Super Tenere
Very good question actually.

I also asked the builder this question. The main function of reverse bows/wave piercing bows is to reduce pitching. Not only is it uncomfortable but it also negatively affects the performance of the sails.

There is also less deceleration as the bows "slice" through the water.

Disadvantages are that it is more difficult to fend off the bows in tight marina spaces, there is a risk of stuffing the bow (on this boat we have curved lifting foils that reduces that problem) and less volume in sail lockers up front.

So in summary it has everything to do with increasing sailing performance. I'm not complaining about the looks either!
An Norwegian guy came up with a sort of inverted bow for ship (google X-box Ulstein). While not as aesthetically pleasing as your yacht's design, it is apparently very effective.
 

silberfuchs

Pack Dog
Joined
Sep 16, 2013
Messages
205
Reaction score
4
Bike
KTM 950 SE
Very good question actually.

I also asked the builder this question. The main function of reverse bows/wave piercing bows is to reduce pitching. Not only is it uncomfortable but it also negatively affects the performance of the sails.

There is also less deceleration as the bows "slice" through the water.

Disadvantages are that it is more difficult to fend off the bows in tight marina spaces, there is a risk of stuffing the bow (on this boat we have curved lifting foils that reduces that problem) and less volume in sail lockers up front.

So in summary it has everything to do with increasing sailing performance. I'm not complaining about the looks either!
Hello Ratel,

Thanks for your answer.
Being a monohull guy (I did mention that earlier) I am principally worried about the lack of reserve buoancy on multihulls.
I saw some rather interesting video footage and read some remarks of crew members on these big 60 foot plus "hurry-around-the-world" racing machines - monohulls n.b. - about what happens when they are surfing down the one wave and dig into the one in front at speeds of 25 knots or higher.
In my younger years I had the chance of crewing on a tornado cat. At much lower speed I assure you we dug the leward hull in and I used the whole length of the trapeze cable not to fly too far off the then capsized boat.

I am fully aware, that these designers have experience and will have tried out a few things before they really build a speed machine like yours.

Over and above all I hope your dream comes true and everything works out well.

Best wishes and greetings, G.
 

subie

Bachelor Dog
Joined
May 20, 2008
Messages
10,981
Reaction score
265
Location
Saldanha
Bike
Honda XR125L
Also waterline length is king. Like cubic inches are for horsepower
 

subie

Bachelor Dog
Joined
May 20, 2008
Messages
10,981
Reaction score
265
Location
Saldanha
Bike
Honda XR125L
Hello Ratel,

Thanks for your answer.
Being a monohull guy (I did mention that earlier) I am principally worried about the lack of reserve buoancy on multihulls.
I saw some rather interesting video footage and read some remarks of crew members on these big 60 foot plus "hurry-around-the-world" racing machines - monohulls n.b. - about what happens when they are surfing down the one wave and dig into the one in front at speeds of 25 knots or higher.
In my younger years I had the chance of crewing on a tornado cat. At much lower speed I assure you we dug the leward hull in and I used the whole length of the trapeze cable not to fly too far off the then capsized boat.

I am fully aware, that these designers have experience and will have tried out a few things before they really build a speed machine like yours.

Over and above all I hope your dream comes true and everything works out well.

Best wishes and greetings, G.
Dont go there :ROFLMAO:
After sailing on a heavy Catamarran like a leopard 40 on a one week trip in deep ocean I am very pro modern cats. Racing ,like with mono hulls, is a different ball game. Things break at sea mono or multihulls. With modern navigation and weather info there is no need to go test yourself and boat in the ultimate storm conditions anymore. This is going to be a wonderfull fast and seaworthy boat(y)(y)
 
Top