Displacement alloy catamarans

bekasi

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Anyone has any info on builders that do alloy displacement cats that has large cockpits that can be optimised for game fishing?
 
Something like these ??

lonabrak_large.jpg


http://www.macduffshipdesign.com/work/6.htm

http://www.macduffshipdesign.com/

They have some good stuff and do a fair bit commercial outfits from fishing to pilot boats..

Ask for Simon Oakes and give my regards .... from MV Navigator..
 
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Southboats build fabulous cats, but they tend to be planning hulls.

The 12m GRP is an excellent boat (I can get you one ratehr swiftly if you need it).
They only do one 12m alloy one and I believe the layout is more windfarm than game fishing. They may provide a hull though.

Pepe Workboats are more semi displacement and gaining a good reputation.
Shogun (second boat picture down) is fairly game fishing orientated, but with short accomodation. She works as a standard charter vessel out of Lymington.
Not sure of any actively involved in game fishing though.

http://www.pepeboatyard.co.uk/index_files/Page338.htm

We don't have many alloy cat builders here in the UK.
Crowther in Australia may be more suitable as a point of contact. They specialise in displacement style hulls too. Many of the massive fast water taxis running the Thames are their design.
Based on a mould of theirs, but built in GRP is the Powerglide Catamaran, built by Rod Baker in Wadebridge, Cornwall.
+/-12m and a true displacement hull they are incredibly economical (3lpnm at 21 knots with 2 x 285Hp IVECOS.
Rod builds a great hull, but his interior fit out leaves an awful lot to be desired.
He is also not particularly good at time management or money management so be careful with your stage payments and make sure you employ a project manager to make sure you get your boat the year he says it will be built.
Rod will build more or less any accomodation and deck configuration you require and the boats do look the business.
To date he has built several standard UK charter boats, very good game fisher style layouts, trawler yacht style layouts and also the boat I managed the build on which was for fishing and documentary filming in the far north of Norway, Troms Explorer. http://www.troms-explorer.com
Ignore Rods own fuel consumption claims, they are OTT, the actual with 2 x 285 Ivecos is 3lpnm.

Make sure you have alloy or plastic fuel tanks fitted. Rod glassed our tanks in out of voids in the hull and then forgot to clean out the swarf! We lost both engines going round Landsend just two hours into our 2100nm delivery journey! The fuel filters we had been supplied as spares turned out to be the wrong ones too!

Do employ someone to manage your build... You will not get it anything like on time if you don't. That's if you get it at all as there is still a game fishing hull 3/4 fitted out sitting in the side of the workshop from about 4 years ago!
Despite all Rods little foiballs (spelling?), his boats are very well worth considering even in GRP. Very well priced too.
http://www.powerglide30.com/index.htm
 
Another good aluminium boatbuilder in Britain is Alnmaritec in Northumberland - www.alnmaritec.co.uk.

They recently built a 12m displacement catamaran OSRV for the Oil Terminal here in Barbados - here are some photos of her : http://www.alnmaritec.co.uk/boats/boats_library/boat_aln096.html
Although I know that this is not the sort of boat that you are looking for......

This might be though : http://www.alnmaritec.co.uk/boats/all_boats80.html
Scroll down to ALN 084 'Lambeth', and then click on the photos and design profile links.
She is 13.5 m long (although I am sure they could scale her down a bit if desired) and does 21 knots with 2 x 200 hp John Deeres on shaft drives - very efficient!

Or perhaps something like this? http://www.alnmaritec.co.uk/downloads/alnDB_74.pdf
This proposal is on their 'Boats on the drawing board' page at http://www.alnmaritec.co.uk/boats/boats_drawingboard.html

And I am sure that the Alnmaritec design office would be delighted to work up a proposal for a game fishing cat with a large cockpit, based on this hull form.
Almost every boat built by them is a one-off and custom designed - with 'our' OSRV, we started literally with a clean sheet of paper (or computer screen) while basing the design loosely on the Waveworker hull form - although the final version ended up being very different.

Oh, and I also know Simon Oakes at MacDuff - bumped into him last at SeaWork a couple of years ago. Their 12 m cat in the photo above certainly looks the business - very impressive (and very good looking too).

And I met Rod Baker about 7 or 8 years ago, when I drove down to Cornwall to have a look at the Offshore 2000 fishing boats he was building then. He is quite a character for sure!
 
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Here's another one.
http://www.alicatworkboats.com/index.php
They have been fabricating boats designed by Global Marine Design, and are supplied as pre cut kits. You can see their catalogue of kits here.
http://www.marinekits.com/catalogue.php?catid=4
http://www.marinekits.com/catalogue.php

A good local builder is Lyme boats in Exeter.
http://www.lymeboats.com/p/about

buckieshipyard.com who have built Al cats.

Here is the list of boat builders who exhibited at Seaworks 2010
http://www.seawork.com/2010_Exhibitors/exhibitors_by_category/vessel_design,_build
 
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ride,stability??

Thanks for the feedback guys! Has anyone rode on a displacement hull cat? Hows the ride & stability? How stable would be a displacement cat with a 5m BOA & 11.5m LOA??
 
Thanks for the feedback guys! Has anyone rode on a displacement hull cat? Hows the ride & stability? How stable would be a displacement cat with a 5m BOA & 11.5m LOA??


Cats are very stable, you only have to look at the huge number that frequent the commercial sector, but not everybody likes their quick righting motion. Their advantages outweigh any disadvantages overall.
I would suggest you arrange a decent run for yourself in a very similar craft in lumpy conditions, offshore where you intend to operate the vessel.
If the builder offers a surveyed/coded version, it would be worth investing a few more dollars in to improve the resale later.
From memory, your location is an island(s) with many tourist resorts, so a commercial game fisher would be good property.
 
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swim/boarding platform

The only issue will be the platform as they have high wing decks,may be a hydraulic operated platform in the inner side of the hull extensions on the two sides.
 
The only issue will be the platform as they have high wing decks,may be a hydraulic operated platform in the inner side of the hull extensions on the two sides.

True game fishers don't have boarding platforms, as they interfere with the retrieval of the big fish via the transom door.
Its going to depend ultimately on the design of the boat you choose, and what is going to look and work right.
 
Thanks Andiemac...yup its going to be the best of both worlds actually...cruiser cum sportfisher! Has anyone seen a platform on a displacement catamaran?
 
The problem for game fishing using a cat is that it won't turn as quickly so that you can keep the stern facing the fish. Sports fishing boats often use a lot of their substantial power to spin the boat quickly so that the fish stays behind the boat where the chair is facing. Thats possibly why you don't see cats as sports fishing boats? The large aft deck is good but this also needs to be down near water level, so you have no appreciable tunnel between the hulls, when hauling in a big fish the transom doors are almost under water so the fish slides in easy.
 
Cats are used pretty much through-out the various Oz game fishing areas, because they have been widely accepted by the local boaters as serious offshore-capable craft over the last couple of decades, and used by search and rescue services.
In saying this, the number of game fishing monos are proportionately still a lot higher.

Understanding that our boating community is tiny compared to other major centres, 'cat-preferred' owners appear very definite about their particular choice of vessel, and would probably never again choose to own a mono hull.

As Neil said, the full flowing tunnel clearance is important in an offshore cat, but I don't agree they cannot turn as quickly as a mono, particuarly in slow close quarters. Trolling speed is around 7 knots generally.
With the engines set further apart I would suggest it would be in fact the opposite, working one against the other.
The cockpit sole will be set higher than an equivalent mono, and dragging large fish aboard could take a bit more 'oomph', but that's just part of the compromise.
 
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The problem for game fishing using a cat is that it won't turn as quickly so that you can keep the stern facing the fish.

Can't agree with that comment.
I have driven and game fished aboard both and a decent Cat will spin very fast indeed with split throttles and a bit of grunt from the revs.

I've driven a displacement Cat over 2100nm in a massive selection of weather.
Twitchy in a big following sea, but you soon get used to that.
Great in a beam sea.
Hard in a head sea once the waves get tall enough to reach the belly of the hull otherwise superb.

The boat barely rocks in any normal sea conditions.
 
The alloy cat in my avatar has very narrow displacement hulls with a length / beam ratio of 15 at the waterline - she is very directionally stable, to the extent that she will happily proceed in a straight line under one engine, despite being 16' wide.
But this also means that she can be a bit twitchy in a following sea as Nautibusiness describes above - if she decides to go down a wave diagonally rather than straight down, applying full helm over is not going to have an awful lot of effect.....

Here is another builder of ally cats in the UK - http://www.alloyboats.co.uk/commercial/

For background reference, it is also worthwhile looking at some of the GRP displacement cats available - for example :

Glacier Bay http://www.glacierbaycats.com/

BW Seacats http://www.bwseacat.com/index.htm - there is a very interesting article here about power catamaran design, comparing planing and displacement hulls.

Blyth Workcats http://www.blythworkcats.co.uk/10m_workcat.htm - their 10m could be considered to be a displacement vessel.

And Malcolm Tennant is quite famous for his displacement cat designs - http://www.tennantdesign.co.nz/
 
The alloy cat in my avatar has very narrow displacement hulls with a length / beam ratio of 15 at the waterline - she is very directionally stable, to the extent that she will happily proceed in a straight line under one engine, despite being 16' wide.
But this also means that she can be a bit twitchy in a following sea as Nautibusiness describes above - if she decides to go down a wave diagonally rather than straight down, applying full helm over is not going to have an awful lot of effect.....

Here is another builder of ally cats in the UK - http://www.alloyboats.co.uk/commercial/

For background reference, it is also worthwhile looking at some of the GRP displacement cats available - for example :

Glacier Bay http://www.glacierbaycats.com/

BW Seacats http://www.bwseacat.com/index.htm - there is a very interesting article here about power catamaran design, comparing planing and displacement hulls.

Blyth Workcats http://www.blythworkcats.co.uk/10m_workcat.htm - their 10m could be considered to be a displacement vessel.

And Malcolm Tennant is quite famous for his displacement cat designs - http://www.tennantdesign.co.nz/



Glacier Bay are superb boats, but sadly I believe they are in (or very close to) financial troubles. Lovely build and finish.
BW Seacats have only recently emerged in the UK. Offering a budget built, but well built commercial product. Not yet driven one, but do have a friend who owns one with the smaller inboard engine option that is kitted out for long range, offshore game fishing. Oddly kept in Eastbourne I believe.

Blyth.... Hmmm forget them if you are serious. Their early 10m had such extreme bouyancy issues forward that they had to resort to fitting a bulbous bow to each hull thus dramatically altering the handling and ride.

Can't comment on Malcom Tennat as never seen one of his vessels.

Bouyancy on displacement cats is always going to be an issue as they do have knife edge bows that continue very narrow for a fare way back along the hull. Tremendously bouyant and stable aft, but not liking too much additional weight forward, particularly not when underway.
The twitchyness in a following sea is simply down to the knife edge hulls behaving like rudders as you dive down the front of a wave. If the boat is a little off straight she will naturally steer in that direction which can be a little disconcerting until you have mastered it... and you will. You get to know how she will behave before she reacts just by the feeling she passes back to you through the helm.
 
Nice looking!!

A sedan version of this would be really good!! BTW,the stern looks nice!!
 
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