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Proa talk


rob denney

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I'll bring another one and we can both drink as well :D

 

Everyone is acting like I'm building a boat, at this stage I am simply looking for funding/sponsorship. But it looks like my point that the boat would generate more press for a sponsor than a boring 40 ft leaner is accurate :lol:

 

The good news is that Rob's boat looks all set to launch this side of Xmas so at least we can argue about more than numbers then.

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[ hull:

Surface area hull, deck and bulkheads, overlaps and tabbing 40 sq m

Base laminate weight, 3.5 kgs/sq m

Additional stiffening and local beefing up for mast bearings 30 kgs

Paint and bog 10

 

Lee hull weight: 180 kgs

 

Windward hull:

Surface area incl deck, bulkheads, overlaps and tabbing 54 sq m (Dave's is 25 sq m)

Laminate weight 3.5 kgs/sqm

Paint and bog 11

 

ww hull weight: 200 kgs quote]

 

 

I'd have to say that is a very light laminate for a 15m boat, or any coastal boat. The outside skin must be very light, and so not very damage tolerant. My 10m cat is 5 kg/m2 and dings easy enough as it is. I've been in seas and situations where I wouldn't want it lighter.

Also 200 gm/m2 of paint is also a very low estimate, even for vacuumed flat panels. I've worked with the International Paints guys on race boats and even being sparse it gets close to 1kg/m2.

So at these weights I'd suggest it is below what many would expect for safety factors and finish.

Many many people have worked hard to make their boats lighter, and if you manage to launch and sail this boat in a rugged coastal race, at this weight, I'll bring a bottle of rum too!

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Guest stormjib

From looking at all the figures on this "magnificent" creation I think Rob's computer must have a strange keyboard error that doesn't let him type 2 zeros together - that would go a long way toward explaining the bulschist weights he is quoting...

NO WAY WILL THIS WORK AT THE WEIGHTS HE IS QUOTING...

IGNORE AND RUN AWAY...............

 

Oh, the F22 looks hot though - probably easily beat the proposed proa (of any length up to and including 50m)

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Can somebody explain why, even with their own thread about the lopsided proas being so quick, they have to come here and bleet to people who couldnt care less about them when all someone is asking is what people think of the F22? Stop threadjacking and go back to your own thread so everyone can ignore it easier!

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Greg W,

Light indeed. As part of the engineering, the engineer supplies some static bend loads to check the beams are what they should be. So far with the masts we have built and tested, the deflections are within millimetres, which gives me a lot of confidence in his numbers.

 

The lack of rig loads is part of the load story, as is low righting moment. The beams are sized for 450 kgs (one of the variables still under consideration) in the ww hull, which is 3.25 tonne metres of righting moment. A GBE has 4.5m cl-cl beam and weighs a tonne so has 2.25 tonne metres rm plus say 250 kgs of crew in the ww hull to give a total rm of 3.5 tonne metres. Not sure what the GBE beams weigh, but the difference is a) carbon vs alloy, B) no mast or traveller loads or fittings, c) the ability to build bulkheads into the carbon tube at stress points and taper the laminate and the section, d) lower safety margins on the race proa as there are fewer unexpected loads.

 

As well as standard hull flying and torque loads, there is material included for the beams to resist slamming loads when the boat comes upright after a capsize or big hull fly (see http://www.harryproa.com/gallery/galleryU.htm for what happens when you ignore these loads) and for one hull stopping in a head on collision.

 

The carbon I use for the lengthwise loads on the beams, masts and rudders is in tow form. Costs $Aus45 per kg, which is half the price of uni cloth and there is almost no wastage. Makes carbon components a lot more affordable, and quicker to build.

 

Building from scratch, I think a 10.5m harry from Polycore, gel coat and vinylester would be pretty close to the ply tri price. Would certainly be a lot quicker to build and more comfortable to sail. Second hand, it's no contest as there are no harrys for sale. Seaworthiness is all about the sailor, but I would much rather be in a storm in a 10m x 6m harry than an 8m tri. Speed? Not many 8m plywood tris do 16 knots under main and jib. And even fewer in 20 knots of breeze and flat water. A 10m harry has 500mm of foam added to each end after the hull is built. So you only need to extend the garage one metre. ;-)

 

rod boy,

Scepticism is healthy, but I can support a lot of my numbers with stuff we have already done. For instance, the mast in the video boat (Rare Bird) weighs 120 kgs and uses glass (weighs 18kgs more than if it was all carbon) for the off axis loads. Rare Bird has 18 tonne metres of righting moment, 5 times higher than my boat, and 50% more sail. Half the weight will be pretty easy to achieve for the same type of mast. My boat will not have a "twig rig". It is a 600mm chord x 200mm thick unstayed carbon wing mast with 15mm thick carbon at the deck bearing. The boom will not be a wishbone (despite the rendering), and will weigh 2-3 kgs.

 

I am unsure where you got the 200 kgs from? The daggerboards, deck gear, headsails, pulpit etc are NOT on the harry. It does not need them. I may need a winch to "untelescope" the mast, but a tube masted boat won't need any winches. The 45 kgs is for the tramp , the sail and battens, halyards, main sheet and downhauls, plus a dozen or so small blocks and half a dozen cleats.

 

I look forward to taking you for a sail.

 

Tim,

It is indeed a light laminate, by current catamaran standards. Not surprising as the proa loads are far lower.

 

The laminates are calculated from first principals by an independant (and costly) composites engineer. I have built numerous harryproa prototypes with the express intention of breaking them for insight into the loads involved. Between us we come up with suitable laminates. They are invariably (and not surprisingly) lighter than those used on conventional boats with highly stressed hulls and rigs. One of my prototypes bounced on a beach for 3 hours in a storm. No damage at all. Anyone dinging a 5 kgs/sqm laminate should try slowing down when they approach things.

 

Re finish: The paint on my boats is to protect the resin from the sun, not to add cost and weight to make them look shiny. Asking high priced paint reps for paint quantities makes as little sense (to me) as asking materials suppliers for laminate specs. The former will err on the side of perfection, the latter on the side of safety. Both will weigh and cost more than they need to.

 

You are correct that many designers have spent (some would say wasted) a lot of time, effort and owners money reducing weight. Strange that so few of them are prepared to do anything except blindly follow the herd, churning out look alike boats. If an unqualified ex yachting bum like me can come up with a low tech 15m cruiser weighing 2 tonnes that sails at wind speed, it can't be that difficult.

 

I look forward to taking you for a sail as well.

 

Stormjib,

Thanks for the deep and meaningful analysis. Do you believe the 2,000 kg 15m cruising harry in Holland? Is it such a stretch to imagine that halving the height and width of the lee hull, reducing the windward hull surface and payload by two thirds, the rig by one third and using higher tech building methods won't result in a much lighter boat?

 

Marshy,

Sorry for the hijack, I was asked to join in to answer questions so I did. Seems no one had anything to say about the F22 so maybe the following will help make up for my imposition on your thread. I haven't sailed one yet, but by owners and designers accounts it is a great little boat, was winning a distance race in Aus before the rudder broke, and is beating the F/C 24 and 25' tris round the buoys. It is a bunch of small improvements over all the other small tris out there, done with Ian's usual brilliance. The one in the Philippines cost $US55,000/$NZ90,000 plus tax and freight. Ian reckons he can build the production one cheaper than this, and hopefully he will. I know the guy who owns the Philippino boat (he chose it instead of a harry), if you want his email, let me know.

 

Rob

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Hi Rob,

 

good to see someone with the courage of his convictions!! I'd be really interested to se the finished product.

 

If it turns out to be as good as your predictions, I may be interested in looking further, and certainly in going for a ride if one is to be in NZ at all - even a ride in Ausy would be cool.

 

Good luck to you and, keep us updated here. The proof, as they say, is in the pudding...

 

Matt

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Following are some numbers from the weight spreadsheet for my boat. Apart from the windward hull, it has all been engineered so I am confident the component weights are correct. Dave/Squid would only need half as much windward hull, and there is 20-30 kgs to be saved from having a tube mast instead of the telescoping wing mast rig. A canted tube mast would make the boat self righting.

 

Dave may also want to build the hulls from carbon as the small amounts required are not that big a cost. I have used glass as the Classe 50 (French 15m multihull organisation, Crepes Wahou and co) requires it and they asked me to enter a harry in next years Route de Rhum (solo France to Guadeloupe) as they want to maximise their publicity. Bit full on for me, so I have got an ex mini 650 sailor to charter the boat, with a smaller windward hull.

 

Lee hull:

Surface area hull, deck and bulkheads, overlaps and tabbing 40 sq m

Base laminate weight, 3.5 kgs/sq m

Additional stiffening and local beefing up for mast bearings 30 kgs

Paint and bog 10

 

Lee hull weight: 180 kgs

 

Windward hull:

Surface area incl deck, bulkheads, overlaps and tabbing 54 sq m (Dave's is 25 sq m)

Laminate weight 3.5 kgs/sqm

Paint and bog 11

 

ww hull weight: 200 kgs

 

Beams 7.5m x 200mm dia tubes, including reinforcing at the hulls 18 kgs each = 36 kgs

 

Rudders, rudder mounts, tillers and extensions: 20 kgs each = 40 kgs

 

Mast and boom: ~80 kgs (non telescoping one will be 20-30 less)

 

Sail, tramp, rigging, cleats and blocks: ~45 kgs

 

Ready to sail: 581 kgs

 

Safety gear for solo Transpac which I would like to do next year: 180 kgs Includes spares and nav equipment, not sure how it relates to the requirements for Cat 1 or Cat 3 in NZ, but seems close to what Mr Wolf has on his boat, so probably close

 

Ready to race, ex crew, food and water: 761 kgs

 

The list does not include:

Daggerboards, cases and the hull strengthening these require. Harryproas have oversize, liftable rudders, mounted on the beams. They kick up without damage in a grounding or collision, are much easier to clean plastic bags and weed off and can be partially or fully lifted to balance the helm or reduce wetted surface.

 

Shrouds, stays, forebeams, chainplates, rigging screws, traveller, winches, jammers, spreaders, dolphin or seagull strikers, jib tracks, turning blocks, and all the reinforcing and fasteners these items require.

 

Jibs, screechers, spinnakers and their sheets and halyards. The rig is a single 50 sqm mainsail on an 18m tall x 600 chord unstayed wing mast which telescopes down to 10m. The boom is self vanging and the controls (halyards, sheet and downhauls) are 3 or 4:1 blocks and tackles.

 

Much bog: The boat is built almost entirely from full length fully or partially glassed flat panels. These are bagged on a table and bent to shape in simple moulds so the surface is fair and ready for paint. All joins have radiuses and/or rebates for the joining glass. Little or no bog and fairing is required. This is a simplification of Derek Kelsall's KSS technique, made possible because there is no rocker in the hulls. We built a 15m hull and decks using KSS last year. Bit of a cock up with the bending and extra glassing so it weighs 200 kgs. Based on the time this hull took and the refinements to the build system, I am pretty confident my boat will be built in about 500 hours.

 

Pulpit (there is no need to go outside the beams), bunk boards and floors (integral with the structure) and wind instruments (with one sail you are either overpowered or not).

 

Samin,

Forgot to mention yesterday, proas are not legal under ISAF, so would not be allowed in the AC. The French shorthanded race organisers and Classe 50 are trying to get the ban lifted, as it applies to the type of proas that were around 30 years ago, which had serious problems. These have all been addressed by harryproas, which are now arguably the safest performance multihull type there is. Look forward to the race.

 

Wolf,

I design simple, fast boats. If you want something apart from tactics, sail shape, steering and opening beers to keep your mates occupied on the boat, talk to a conventional designer. Complexity is what keeps them in business.

 

Re the banning. Ask Jason, ex Split Enz and NZMY Commodore at the time. He visited us in the shed, before the boat was even joined together or rigged and told us we could not enter regardless of whether the accommodation etc qualified (it did) or how many miles we sailed pre race. The boat looked a bit different back then to what it does now and we had a pretty hot crew lined up to sail it.

 

Rod Boy,

Let me know which of the above numbers you find hard to believe, and why.

 

W (a cat, not a proa) did not have a cat 3 certificate, but would have got one if we applied. Not much point after we were told it would make no difference. It was a long time ago, no hard feelings, I was just setting the record straight.

 

No build blog, but if you join the yahoo harryproa chat group in July, any updates and pictures will be there.

 

regards,

Rob

 

Mate, you were asked what is the weight when you sail this boat with its crew in a Cat3 race like the coastal.

You are the designer and you have a great list of numbers of which some are nonsense, such as the skin weights and the paint weight.

Plus you have to join these panels together and glass in your bulkheads, beams etc.

Most professional designers work everything out correctly and give an accurate figure.

Your 700kg has more gaps in it than a swiss cheese.

 

Secondly the Coastal Entries are not decided by one person. the boat has to have Cat3 before it can race. I doubt very much "W" meets the accomodation requirement, (especially as you state you had a hotshot crew lined up, implying more than one ?), but the Cat3 requirement is far greater than just accomodation. It includes minimum scantling, beam structure, seaworthiness requirements.

W is just so far off getting Cat3 it is not funny, I mean it has little bits of alloy and string connecting the two tillers. I remember a few years back it was sitting at its marina swamped after some particularly unpleasant 6" waves got the better of it at its very sheltered dock !

 

But like I said, you get cat3 for your Proa and it can race.

Bring it on!

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Greg W,

Light indeed. As part of the engineering, the engineer supplies some static bend loads to check the beams are what they should be.

 

I don't recall questioning the engineering or any of your structural data.

 

However I suspect you may be a little out of touch re costs. So far I have spent 5.5k inc GST on materials to build my 7.6 metre tri. That will build the hulls and beams sheathed in glass/epoxy. I estimate that to have these complete, and painted including custom stainless fittings (read bent bits of flat bar) and bolts will, conservatively, cost a max of 10k. Thats about 7.8k australian incl GST. Could you build the Harrigami platform for that in equivalent materials ie. the strip and epoxy of the prototype? At the prices (incl GST) an amateur would have to pay?

 

You state "but I would much rather be in a storm in a 10m x 6m harry than an 8m tri". Thats fine, but can you qualify that statement? I don't see how an 8 x 6m tri would be much different from an 8x6 bi-hull with one hull a couple of metres longer. Also I think that having the rig right near the edge of the platform might be a little unsafe in bad weather should you need to tend or repair it. I hope the telescoping mast on your new boat never seizes in bad weather and you have to try and free it.

 

I've been following the development of your boats since the harrigami article back in 2001. I've witnessed many discussions around them that you've had in many fora. You come across as if a Harryproa is merely a different sort of multihull that everyone should want to build. But they are actually a different type of boat altogether, bearing very little resemblance (other than multiple hulls) to any other traditional or contemporary proa or multihull. People tend to be resistant to change, as well as I suspect, assymetry.

 

Your arguments seem to revolve around proving that your boats are 'better' than everyone elses because they are (on your assertion) cheaper to build, quicker, allegedly more safe etc etc. But you know, in the 7 or so years I've been watching you promote your boats, I have yet to hear a cogent argument as to why I should have built one of your designs against the one I eventually chose, for the type of harbour and coastal sailing I have in mind. My boat won't do anything 'better' than yours, as a Harrigami won't do any thing 'better' than mine. Different strokes etc. You need to live with it and stop trying to convert people. If people perceive any genuine advantages they will be interested.

 

One thing I will be able to do, should the mood take, is get out and race against some other boats of similar performance. This doesn't seem to happen with Harryproas as, by your admission, the owners are all cruiser oriented.

 

I'm looking forward to the option of heading down to Central on race day morning, being paid to adopt a couple of Piedy dero's from the drunk tank, lashing them to the weather hull before the're fully conscious, throwing up the biggest kite I can find, seeing if I can lift the main hull out of the water and trying to spear a GBE in the process :twisted: .

 

Or I may go fishing. Nice to have the choice.

 

BTW my garage has been extended to the max :wink: .

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Greg, I would have to say that your post would have to be one of the most well written, considered and, despite its apparent length, succinct posts I have ever read on this site. Squid I suggest this post deserves a bottle of rum. I think you've conveyed very well everything the rest rest of us could not - except the bit about spearing a GBE - my flimsy raft does not like the sound of that!

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But you know, in the 7 or so years I've been watching you promote your boats, I have yet to hear a cogent argument as to why I should have built one of your designs against the one I eventually chose, for the type of harbour and coastal sailing I have in mind.

 

yes 7 years of talking up how fast this Harryproa thingy is without a single result!

stop talking it up and get a result!

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Seeing as the title of this discussion is about small day sailing trimarans I thought I would share my latest offering.

This is a 6.3m trimaran aimed between those sailing F 18's and more expensive trimarans with accommodation.

Hull shapes are wave piercing, but with underwater shapes designed for dynamic lift. The rear beam is curved to match the mainsheet load, and the front beams are inline with the stays, and to move the beam intersection with the floats aft, to minimise drag, and reduce load induced twist in the structure.

The square top mainsail is (of course) boomless, the battened jib is self tacking, and the extras on the prod can be either roller furling screachers or gennakers.

It is designed for two crew, with the options of trapezes, or for day sailing with up to four aboard. A small outboard can be used from the main hull, the rudders are in each ama.

The boat is demountable, and can fit in a standard 20' container for export from the builder in Thailand.

Length 6.27

Beam 3.6m

Weight 250 kg

Mast 9m

Sail area 25 m2 upwind

Gennaker 21m2

TC 627 150509 tri.jpg

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Funny old world ain't it. I like Rob's boat and would like to build one, a cruiser if it's my money, a racer if it's someone else's money. Yet I agree with nearly everything Gregw says.

 

Let's have a look, would a Harrigami cost the same as a 7.6m tri. Quite possibly, you don't give us the weight of the tri, but if the quantity and quality of materials were similar, then prices should be too. But I suspect the proa would get cheaper when you get to the rig and other stick on bits.

 

In a storm longer/wider is always going to be better, do I have to explain that?

 

The telescoping mast is a new idea, yet to be tested. I like new ideas.

 

Is fora the plural of forum? Maybe fori? guess it depends on whether it is greek or latin, better than forums.

 

I think Greg made the right choice of boat with the tri. He wants to race others of the same ilk and there is no fleet of racing proas to join, and may well never be as I don't see the whole world changing their prejudices and building proas. For Wed night racing, winter series, w/l the proa is unsuitable, stick to the tri (or cat).

 

But for cruising (shorthanded) ,passage races and shorthanded races I will go for the proa.

 

The biggest downside to the proa as a cruiser is also it's biggest asset, the length. You pay per metre in many places , and in Aus and Europe now there are more dumbshit rules being introduced for boats above an arbitrary 15m, I'll make mine14.95m.

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Funny old world ain't it. I like Rob's boat and would like to build one, a cruiser if it's my money, a racer if it's someone else's money. Yet I agree with nearly everything Gregw says.

 

Let's have a look, would a Harrigami cost the same as a 7.6m tri. Quite possibly, you don't give us the weight of the tri, but if the quantity and quality of materials were similar, then prices should be too. But I suspect the proa would get cheaper when you get to the rig and other stick on bits.

 

In a storm longer/wider is always going to be better, do I have to explain that?

 

The telescoping mast is a new idea, yet to be tested. I like new ideas.

 

Is fora the plural of forum? Maybe fori? guess it depends on whether it is greek or latin, better than forums.

 

I think Greg made the right choice of boat with the tri. He wants to race others of the same ilk and there is no fleet of racing proas to join, and may well never be as I don't see the whole world changing their prejudices and building proas. For Wed night racing, winter series, w/l the proa is unsuitable, stick to the tri (or cat).

 

But for cruising (shorthanded) ,passage races and shorthanded races I will go for the proa.

 

The biggest downside to the proa as a cruiser is also it's biggest asset, the length. You pay per metre in many places , and in Aus and Europe now there are more dumbshit rules being introduced for boats above an arbitrary 15m, I'll make mine14.95m.

 

Squid, you have raised some points I don't have time to address now.

I just want to make it clear that I haven't lost sight of the fact that Rob has basically invented a new type of yacht with the harryproa and spent a bunch of his own time and money with prototypes getting the concept sorted. Thats more than most of us will do and he deserves to be commended for it. I think there is some real potential in the larger sizes as long-range cruisers. But thats not what I'm into.

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In a storm longer/wider is always going to be better, do I have to explain that?

 

.

 

And what you wouldn't give in said storm for some freeboard and by the looks of it, some shelter.

 

Excellent post by the way Greg.

Here was I planning to pick holes in the design numbers because some of them are nuts, but you said it way better.

 

Its still a nice light boat, I'm sure will be very fast in a straight line.

whether it is suitable to race Coastal or Route de Rhum is the big question as I see it.

 

But good luck to anyone who decides to have a go in one of these, you must have nuts the size of an elephant !

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I just want to make it clear that I haven't lost sight of the fact that Rob has basically invented a new type of yacht with the harryproa and spent a bunch of his own time and money with prototypes getting the concept sorted. Thats more than most of us will do and he deserves to be commended for it. I think there is some real potential in the larger sizes as long-range cruisers. But thats not what I'm into.

 

Here here. Rob's ideas may not suit your tastes and may not even be new (i think the pacific islanders were sailing similar things many years ago) but give him credit. There's a lot of his designs built and sailing by happy owners all over the world. Anyone criticising should probably line up their acheivements over the last 7 years. And if the boat ends up heavier than planned so what, hands up those that haven't launched an overweight boat. David Barkers specs say Sundreamer weighs 4880kg, she's at least a tonne over that. Want me to name some others, I bet not?

 

I'm a little disapointed at some of the criticism. It's not what I'd expect from multihull guys. I thought we were above kicking someones individuality, thats why we sail multihulls. There's boats in our fleet with some pretty stupid ideas and some unsafe ones. We rib one another, we don't throw sh*t like some have in this and the other thread. Who here hasn't finished a race coz their boat was underbuilt, yep it broke, it was underbuilt, thats how we know when we've overbuilt something, it doesn't break.

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Been watching this thread with interest, it's fun watching the multi boys bash at each other. Us leadswinger guys are so much nicer people. But we already knew that, didn't we :)

 

Proas rock and I'm almost, note almost, willing to bet we could get a hollowed up coconut palm Proa from one of the Pacific Island and it would beat most if knot all boats in the CC, assuming a nice breeze. It would beat most at least.

 

So while you ponder your next set of gladwrap string sails, carbon dodackies and CAD designs, just realise that with all that technology and money the chances are you will still be slower than piles of dudes in hollowed out logs already plying the seas of the Sth Pacific.

 

Maybe you should be talking to the wizened up old dude who builds the boats for the Bishop of Kiribati, with only a axe, his eye ball, a coconut palm, some plastic sheet (like the stuff you lay under concrete) and the thighs of a few big ladies :) :) :)

 

No offence intended Rob or other designers/builders. Just an observation really.

 

PS. nice post SD. It surprised me it took someone that long actually.

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Island time,

You are definitely welcome for a sail! Things rarely turn out as well as predicted, but it will be fun trying.

 

MrWolf,

On what do you base your statement that the skin weight and paint weight are "nonsense"?

 

Coastal Classic Weight: Which part of the following from my earlier post is not clear?

"The weight ready to sail: 581 kgs

Safety gear for solo Transpac which I would like to do next year: 180 kgs Includes spares and nav equipment, not sure how it relates to the requirements for Cat 1 or Cat 3 in NZ, but seems close to what Mr Wolf has on his boat, so probably close

Ready to race, ex crew, food and water: 761 kgs"

 

Paint: Using Tim C's numbers of 1 kg of paint per sq m and assuming Timberwolf weighs 950 kgs and has surface area of 100 sq m, more than 10% of your boat's weight is bling. Costs you at least 5% of your performance, more than 30 minutes in a 10 hour Coastal Classic. This is wasted weight, money and time to me, but if it makes sense to you and Tim C I guess we just have to agree to disagree.

 

Weight: From my earlier post

"Surface area hull, deck and bulkheads, overlaps and tabbing 40 sq m"

"Beams 7.5m x 200mm dia tubes, including reinforcing at the hulls 18 kgs each = 36 kgs" Tabbing is the joining of bulkheads, deck and hull. Using edge radii, the joined area is lighter than the base laminate. The "reinforcing at the hulls" is what holds the beams in.

 

W was 10 years ago. It was, (for the third time!) completely different to what it is now and would have got Cat 3. Jason said no way. It didn't mean enough to us to make a fuss. Still doesn't, I was just setting the record straight. Apart from it winning me 10 grand in a Royal Institue of Naval Architecture (RINA) design contest 8 years ago I have had nothing to do with it since then. So could you please stop bashing me over the head with how bad it looks now?

 

Re your latest post. Greg did not mention the weights. Please pick holes in them. It would be a bastard if I have made a mistake and you didn't let me know just because Greg wants a tri, not a proa. And don't let all the nice people "kill your joy". I like criticism, it makes me think. But please, back it up with numbers or facts, rather than sweeping generalisations which very quickly get boring.

 

I will be happy if it is "fast in a straight line", but what aspects of the Coastal and the RdR won't it do well in?

 

Greg W,

You queried the weight of the beams, I told you how I arrived at it and why I thought it was correct. Hard to do this without mentioning engineering.

 

I have detailed the retail costs ($4868 for hulls and beams) of a strip planked 10.5m I built a few years ago at http://www.harryproa.com/harrigami/hgmatlist.htm and the time (449 hours) it took to build at http://www.harryproa.com/harrigami/hgtimelist.htm Pretty sure I could do it quicker and cheaper using flat panels, but won't know for sure until the 15m is built. I could certainly build the mast now for less than the $7k on the list.

 

Storm comparison is a bit tricky without knowing anything about your boat, but the advantages of the harry platform are: A double ended boat is much easier to deploy sea anchors and drogues from. A 200mm draft boat with completely liftable water foils is much less likely to be capsized than one with deeper draught. A 10m boat with high prismatic coefficient is less likely to pitchpole than an 8m one with moderate Cp. A 6m wide footprint is less likely to capsize sideways than a 4m wide one. An unstayed rig is much easier to depower than a stayed one, especially downwind. The mast in the centre of the hull is far safer than a foredeck or a cabin mounted mast. There is less to break on a harry. Happy to discuss these in detail if you want to. Would also like to hear any other problems you anticipated with a harry, please.

 

I also hope the mast never seizes in a blow. That is why I am trying it on my boat before anyone else does. Be pretty cool if it works though.

 

The rest of your post is quite correct. It is a variation on the one monohull sailors use to explain why they don't want a multi. Fair enough, it would be very boring if we were all the same.

 

I gave up on the semantics of proas years ago. My argument for someone having a harry is they are for people who want cheap, fast and easy to sail and build. I have demonstrated these as well as I can (see above web pages and the rest of the web site), but a few people don't believe my numbers. Again, fair enough. So I offer the video of the 15m 2,000kg cruiser sailing at windspeed. As usual, no one comments on the video, the boat or the likely performance of one weighing a quarter as much, focussing instead on the amount of paint on my race boat, or something equally inane.

 

If it had been my choice, I would have built a race proa 10 years ago and gone out and kicked arse or died trying. Life got in the way, so I got involved in building and selling cruisers while I improved the breed. I am now in a position to build and campaign a race boat, so we shall see what happens.

 

Samin, 10 years, not 7. I have plenty of performance data, but without pictures or race results it is too easy for cynics to devalue it. So I offer the video. Did you look at it? Any comments? Any vids of your boat (or any other) at 15 knots in 15 knots of breeze under main and jib, with the crew dry and bored?

 

Tim C, Nice picture, but that's not a spec! :-) It won't get get discussed here without a break down of the component weights, the laminate you are using and how much paint is on it.

 

There is a guy in Malaysia asking about "the right multi" on SA. They are trying to sell him a Multi 23. Drop him a line, you might get a sale. Sell as many as you can now, because once the F22 production comes on line, I predict the small tri market will be as hard to crack as the medium tri one was once the F27 etc were launched.

 

Squid,

Harrys are extremely maneuverable (bow and stern rudders, ability to stop dead on any point of sail and either wait, go in the other direction or crab sideways). They will be a blast on Wednesday night races! And with a bit of practice, they will shunt as quickly as an overlapping genny boat will tack. The length is a nuisance. Mine has removable ends so it goes in a container, but it takes a day to put them back on. Next idea to try after the telescoping mast is folding ends for trailering and marinas. Yet another advantage of no headstay on one end or rudders on the other.

 

The rest of you,

Thanks for the encouragement (on and off list) and the introduction of reality. Should be quite a party if I do get it to NZ! By the way, there is a 12m cruising harryproa sitting at Coffs Harbour waiting for a weather window to leave for NZ. It is heading for Whangerei, so if anyone sees it there, please let me know.

 

regards,

 

rob

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Beams 7.5m x 200mm dia tubes, including reinforcing at the hulls 18 kgs each = 36 kgs"

 

rob, what is the wall thickness of these beams ?

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