ALLOY CAT BUILD

[peterbo3]

http://www.platealloyboats.com

You might want to take a peek here. Bullshipper in particular. :D :D :D

[Chaps]

That looks a lot like Skypoke's build which was a kit from down under as I recall.

This fellow is doing a great job of documenting the project on his website, it will be fun to watch.

[Bullshipper]

Chris Tucker is a very talented australian naval architect that worked with Roger Hill in New Zealand and me in Mexico when I had my cat plans comisioned. He is working on his own now and has built some nice yacht class cats in Au, as well as designing for kit builders.

Hill and Tucker market cut plans, not kits, so in Skypoke's case, he had Metalsales in New Orleans nest and cut the the pieces for him. The freight on these items would have neen cost prohibitive, where the autocad software plans cost nothing to transport.

[CTMD]

This boat is part of the range of Powercat kitsets I designed for Plate Alloy Australia (www.platealloy.com). They range from 6.5 to 11.5m and are designed to be built by the home builder with the boats actually being built upright. With the exception of the 6.5 all can be fitted with stern drives or outboards. For those not in Australia we can arrange to have kits cut locally. Kits can also be modified to suit your requirements, for example the 8m below was given extra head height to suit the taller the "usual" client.



For more info contact John Pontifex: sales (at) platealloy.com

[CTMD]

At Welder's request this is the boat being built..

Linky

[Bullshipper]

Chris,

In the USA, there are only 3-4 builders producing alloy catamarans, and due to a high number of panels that most designers draw into their designs to make
2 sponson planing surfaces
4 lower panels up to
2 splash chines
2 outer gunwhales
2 caps
2 transitions to the tunnel
and a large tunnel piece

all contribute to drastically increase the material, material waste factor and total linear feet of double sided welds. This makes alloy catamarans very expensive for our market, especially compared to the NON ALLOY compitition that can pop them out of a mold and are a lot cheaper in the states than in the more expensive southern cross marketplace, or when compared mono hulls anywhere.

American designers like Maxwell have reduced the number of panels and their pricing to make a 29x10 cabin style boat, trailer, and motor packages in the $130K USD range which is a good price considering the increase in alloy prices.

If the # of panels and thickness can be can be reduced, then the alloy cat will be a winner here as their ride is unequeled, especially when the packages are light to begin with, IMO.

[CTMD]

Jeff,

These boats have been designed with the home builder in mind. As such the priority list was....

1. Easy to build (upright)
2. Minimum number of continuous welds
3. Minimum number of parts
4. Minimum amount of ali.

The 8m has:

5mm bottoms and internal structure.
4mm sides
3mm decks and cabin tops.

This boat is quite a bit lighter than Skypoke's and also much quicker and easier to build. This has mainly been at the cost of styling as the simplified build proceedure leads to a more commercial looking boat.

In contrast are the boats I'm currently designing to be mass produced in China. Because they have similar Ali costs but much cheaper labour rates the chinese boats are far more complicated to build but use even less ali and are better looking.

[Bullshipper]

Sure would like to see some drawings for the 8 m Chris.

I also really like the frames you have engineered for the upright home build.

[CTMD]

Ask and you shall receive:

http://www.platealloy.com/cats.htm

[peterbo3]

Jeff,



In contrast are the boats I'm currently designing to be mass produced in China. Because they have similar Ali costs but much cheaper labour rates the chinese boats are far more complicated to build but use even less ali and are better looking.

Hi Chris,
So what is the welding going to be like & will Chinese made 5083 or 86 be used? Or will the plate come out France or the US?
IMHO, Chinese metal generally is CRAP. They seem to lack the quality control required to produce good steel or alloy. And a lot of their "knock off" products, when compared to the original item made in the developed world, are way below standard.
If you have the cash to pay north of $100K for a boat, then you are not going to worry about saving a few grand by having it built in China. Custom alloy boats are just that. Custom built. :shock: :shock: :shock:
I will pay the extra & have it built to a standard in Australia, not to a price in some Chinese sweatshop. And I reckon that plenty will agree with me. :roll: :roll: :roll:

[CTMD]

Peter the boats will be 5083. I'm not sure of the source but I can tell you its very similar in price to what we're paying here.

The chinese builder came to me and asked me to design some boats. This isn't a case of me shopping work to China to save money for my clients. As you say there will always be demand for custom aluminium boats and thats where most of the money is for Australian (and American) boat builders. However there is also a market for off the shelf product and it is this market that my client is targeting

Chris

[peterbo3]

Hi Chris,
All is good. Take their money & give em the plans.
I would like to the market research that the Chinese have based their sales projections on. Sales will only soften here & in the US. Top level boats will sell but it is going to be a hard row to hoe for the mass produced stuff. A number of Brisbane boatyards & boatbuilders have already folded.
Looks like a few tough years ahead.

[Bullshipper]

[quote="peterbo3"]Hi Chris,
All is good. Take their money & give em the plans.
I would like to the market research that the Chinese have based their sales projections on. Sales will only soften here & in the US. Top level boats will sell but it is going to be a hard row to hoe for the mass produced stuff. A number of Brisbane boatyards & boatbuilders have already folded.
Looks like a few tough years ahead. [/quote]

Lots of economies are making money at our expense, and the devaluation of the dollar is making USA products cheaper around the world.

I outsource a lot of production here in Mexico and we have exported to China, beating out their local guys, even after paying the freight.

This is accomplished through productivity through design and Chris has the right approach with less labor, less material handling and waste, fewer parts, and aussie welding techniques are world reknowned, so I wouldn't give up the ghost just yet.

[Bob5292]

I'm curious about what happened with the Maxweld 28x9'6 cats they were planning on making. I know one of the members here has one, but I understood they were going to make 10 in 2008 and I haven't heard or seen anything about them. I spoke to a dealer at the Seattle Boat show and the cost had crept up quite a bit from the original $130k estimate.

Bob

[Bullshipper]

[quote="Bob5292"]I'm curious about what happened with the Maxweld 28x9'6 cats they were planning on making. I know one of the members here has one, but I understood they were going to make 10 in 2008 and I haven't heard or seen anything about them. I spoke to a dealer at the Seattle Boat show and the cost had crept up quite a bit from the original $130k estimate.

Bob[/quote]

They started quoting $120 factory diect, then there was some doubt that the 175's would be enough to push them as predicted, then they showed the same hull around to a few boat shows, then the economy slowed....

These are nice hull, but I personally feel that an 11'11" beam would really help to widen the isles around the cabin and the cabin itself. 9" extra each of these areas make a world of difference IMO, and 30 more inches of beam would make this light hull super stable.

[CTMD]

For those that are interested Greg has updated his web site.

[Chaps]

I was wondering how Greg was doing, thanks for the update.

Its looking good - lots of work welding it out

[CTMD]

Greg is back into it.....

Follow the original link.

[keith]

What are the advantages to a cat verses a mono hull and are there any disadvantages?

[CTMD]

Cat advantages:

Top speed
Stability at rest and underway
cockpit space
fuel efficiency

Cat disadvantages:

More material = more expensive
more continuous welds = more expensive
heavier = more expensive to tow
Taller = less attractive at trailerable sizes

[JETTYWOLF]

two outboards versus one.

[welder]

Chris, would you rather be in a Cat or a Mono adrift in a beam sea and which one would you rather be in in a following sea ?

And lets say these boats are both in the 25' to 30' range .

Do you prefer a Planning or a displacement hull on the Cats ?

Just trying to get some talk started here [ Pros and Cons ] of both hulls, we know there is no perfect ONE boat .

Everyone should have at least 3 different boats for all occasion's , right ?

[CTMD]

All things being equal, I'd take a cat in any seas.....

Unless you're in breaking beam seas the cat may feel like it is rolling about more, however, it is only staying level on the "local" water. A mono is far more likely to generate a true roll and keep going.

Displacement v's planning is a difficult question and it is not black and white you can also get "semi planning" or "semi displacement" that is a boat that generate some hydrodynamic lift without ever truly planning.

Displacement cats make great long distance cruisers, however, this is at the sacrifice of speed (obviously) and also of internal space as the hulls tend to be much narrower so you can't fit good cabins in them.

Planning boats have more internal volume and tend to look better as they can have lower wing decks.

From experience the advantage between cats and monos swings backwards and forwards with size..

<6-7m a cat offers little real advantage over a monohull and depending on cabin type may actually have less useful space.
6-7m-->12-13m The cat is superior in all ways, performance, stability, internal space.
13m--> 16m The mono gains a lot of advantages by being able to fit centre line cabins under the saloon sole.
16m+ The cat hulls are now wide enough to fit decent cabins in (no more quarter berths) and space speed etc become Superior.

Having said all of that we'd draw about 10 monos for every cat. Because thats what the boating public "prefer".

[peterbo3]

Les,
I will jump in. Hope it is not considered a "thread-jack".

If I am adrift in ANY sea, & by adrift I mean without power (no fuel or engine failure), I will have my sea-anchor deployed in a flash. You absolutely have to be bow-on if you are caught short offshore.
No sea-anchor? Improvise. Use a bucket, cooler or anything else that you can tie a rope to & float out off the bow to keep you bow-on.
Calling for help or activating the EPIRB is all good but you have to control your situation until the cavalry arrives. Perhaps we could run a thread on small boat handling when things go pear shaped.

OK, back to Welder's original question to Chris.........................

[welder]

Chris , Just for fun,
A guy is looking at both, Mono and Cat , both 9 meters. What are we looking at in $$$ to build also both boats are rigged with the same gear, electronics and motors [2 ] .

Just a ballpark figure [ This is NOT a real quote ]