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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  
Bob Perry

My newest project

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I like this keel arrangement. With all the barely-marked drift-netting off the Irish coasts, a full keel has the great advantage of saving a lot of drama (and potentially some expensive damage and difficult encounters with irate fishermen).

 

I know a few people who experimented with tie rods between fin keel and skeg rudders (as line and net deflectors), but nobody who has particularly happy with the results. So a cutaway in the trailing edge of a full keel seems like a better approach, potentially giving excellent drying-out-alongside possibilities.

 

The only designs I have seen which comes close to your keel config is Chuck Paine's redesigns of his classic Annie, and his much larger 44-foot Gusto (Paine's PDF). But Paine's cutaway is much less radical than yours, and his boats retain a rather heavily-raked rudder (which you avoid). Gusto languished on the brokerage market for years, so I wonder if the design was really a success?

 

It seems to me that the difficulty with your concept is similar to that of a skeg: how to make that keel-to-rudder stick strong enough. There's an interesting engineering challenge there.

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No problem with that Legs. Perfect place for carbon or welded steel. Not a concern at all. Now making the shapes all blend together might be another thing. But I have Rasper on my side for that.

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I don't think there is anything very new about having the rudder land on the heel of the keel, like the one YMT posted. Here is Ted Brewer's Grand Banks 28 from long ago. I think I saw one once, on land, in winter, under cover. The hull is flat-bottomed, nominally a dory, which helped make it easy to recognize.

 

Grand-Banks-28-layout-&-pro.gif

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My approach to the problem is a far cry from that. I have a real problem with excessive trailing edges and long tip chords. But I see your point. I never claimed to have innovated anything. Even IP has been moving in this direction with their full keel models. I simply looked at how people had been doing it and said, "I can do it better." A typical reaction of mine.

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No problem with that Legs. Perfect place for carbon or welded steel. Not a concern at all. Now making the shapes all blend together might be another thing. But I have Rasper on my side for that.

I'm sure you know what you are doing.

 

I was just thinking of that drying out alongside an old quay situation, where the promised clean bottom turns out to include a rock somewhere around the just ahead of the rudder. That would leave the unsupported connector piece carrying a lot of load ... at a place where any deflection may sabotage the rudder.

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Legs:

Yes, all those things have to be considered and will be. This is not my first rodeo.\

My plan at this stage is to make that piece removable. Just not sure what material I'll use yet. I'm lucky to be working with a builder who is a whizz at anything in metal or composite.

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Pretty much what I had in mind Yves-Marie but I'm not keel on that sloped tailing edge. What kind of thickness ratio would you work with on a keel like that?

This is a metal boat and I can push the slope without the fear of having the top trailing edge vulnerable.

I worked a thickness of 9 top and 11% at the tip.

post-32003-0-87198500-1423947464_thumb.jpg

post-32003-0-24979300-1423947652_thumb.jpg

post-32003-0-81690900-1423947662_thumb.jpg

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We have fish traps in this area that are particularly nasty. Nets laid in the water and left there to trap fish. Near the surface there's a line between floats which I describe to crew as "big red balls." They seem to know what I mean. Between the balls one can be confident there's a line taut enough to wreak havoc.

 

I've experienced this once, in the waters between the Sakonnet and East Passage in RI Sound, to those in the know.

 

I freaked out. I knew I was tempting fate but I missed the trap. As we went over I watched the line below the water trace my bottom. A gradual slope down as it went under the keel, "fell up" quickly off the keel. Rudder next. I held my breath as the line hit the leading edge. Felt and heard an underwater "twang" as the line caught the spade rudder and made it under. Somehow. We carried on.

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Thanks Yves-Marie. I think I'll stick with my 8% foil. Your keel is interesting but I'm certain I could never sell that to my client. He's nervous about the amount of forefoot I have showing already. I'm not budging.

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That's sweet Bob. I guess you are my Valentine!

 

Looking forward to showing the cretins here how yacht design gets done these days, Stay tuned!

 

I can hardly wait until I get Bob's prelims for this project and can bring it into the 3d space where we can all really take a close look at all that entails. I'm very grateful to Bob and his client to invite me to be part of the process. All you lurkers here don't know just what a gift this is to you as Bob is very generous to share so much of the interface that takes place between he and his client and down the road the interface with the builder. This is a very special meeting of the minds and I'm sure that it will provide much to those that follow this thread.

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I can hardly wait until I get Bob's prelims for this project and can bring it into the 3d space where we can all really take a close look at all that entails.

 

Only 3d, Rasp? I'm a little disappointed.

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Here is a more detailed look at the layout. I work in 2 so I have to look at the interior from three different perspectives, plan, profile and section, to make sure everything fits and works as planned.

Twin quarter berths, twin pilot berths and settee berths. Head to port fwd. Shower to stbd fwd, Large refer/freezer to port aft of large nav station. sit down wet locker aft and another fwd in "dressing room". No minimum tolerances.

luckardson%20int%20A_zpsbiitkx3i.jpg

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I like the open, seagoing layout and the lack of a v-berth. Too many layouts are compromised by the quest for a hotel room up there.

 

But without a v-berth, couldn't some of the shower/toilet stuff go a little further fwd? Or is the huge forepeak stowage a requirement?

 

PS Couldn't you rig up a bit more space in the keel for stowing contrabrand?

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Bob, it looks like this yacht has the same cockpit sole hatch as Dave's boat. Van Diemen has the same and it works well, however access from the sides and fore and aft is a bonus, especially for dipstick and header tank checks. The hatch sits on a (drained) channel frame and has a soft gasket so no water gets through. I am modifying the installation so it will hinge (loose hinges) on the stbd side and has dogs near the corners. Have never needed to open the hatch in a seaway and would prefer to keep it that way.

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Globs: Happens to be the exact detail I used on Amati over 15 ears ago. In the case of the new cutter we will have access through seat hatches and a watertight door under the companionway ladder. We are covering all bases as we know that engine space is going to fill up quickly.

Luck%20XYZ_zpsrmjtxdef.jpg

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Humbly suggest that the settee backs are angled rather than vertical. Makes lounging about telling apocryphal stories much more comfortable, rather than having to sit up straight and pay attention.

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I love it! Obviously the owner plans to make passages.

 

Make sure both engines have seperate fuel systems, with the ability to feed either engine from the tanks.

 

Also try to make the chord as thin as you can on the "full keel". ;)

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Also: I am not sure how you do it, but the anchors could get fouled up on the bobstay, especially with an electric windlass! Maybe have the windlass controlled at the bow, no remote?

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Greeves: I have done a lot of bowsprit boats with anchor role out on the sprit and it doesn't seem to be a problem.

Engines will be independant of each other.

 

Pom:

Seat back cushions can be contoured, wedge shaped as drawn. Have to balance between pilot berth width requirements and settee berth requirements. I'll revisit this in the future as I plod my way around the design spriral.

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Have to balance between pilot berth width requirements and settee berth requirements. I'll revisit this in the future as I plod my way around the design spriral.

Your job would be so much easier if you could also design the shape of the humans. Keep them all below 5'8" tall and you could cut cabin height and berth lengths. Make them super thin and you could usefully narrow those pilot berths.

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Greevs:

Don't know why not. But I have 6" high bulwarks and I want to have sufficient scupper area and placement to get rid of green water. Owner wants watermaker and we have plenty of volume for big water tanks. Not sure how many gallons we will go with yet. With all the displ we have tank volumes are not too much of a challenge for a change. Not sure collecting rain water is a concern at this stage. Client has never mentioned it.

 

I'm still fussing with my jpeg making skills. This one is a bit better.

Luck_zps1sfum8nj.jpg

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Greeves: I have done a lot of bowsprit boats with anchor role out on the sprit and it doesn't seem to be a problem.

 

 

If you permanently attach a nylon snubber to the lower tang for the bobstay you will eliminate the rattle when the chain crosses under the bobstay and also will lower the angle of the rode. Wichard (and others ?) makes a chain hook with a retainer. A light messenger attached to the hook allows easy retrieval in lieu of using the boat hook

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We have fish traps in this area that are particularly nasty. Nets laid in the water and left there to trap fish. Near the surface there's a line between floats which I describe to crew as "big red balls." They seem to know what I mean. Between the balls one can be confident there's a line taut enough to wreak havoc.

 

I've experienced this once, in the waters between the Sakonnet and East Passage in RI Sound, to those in the know.

 

I freaked out. I knew I was tempting fate but I missed the trap. As we went over I watched the line below the water trace my bottom. A gradual slope down as it went under the keel, "fell up" quickly off the keel. Rudder next. I held my breath as the line hit the leading edge. Felt and heard an underwater "twang" as the line caught the spade rudder and made it under. Somehow. We carried on.

I stay offshore at least a few miles when transiting between Sakonnet and Brenton Pt for that reason. Those traps are not marked and their positions change. And if you do get caught it is not advisable to jump out to clear the line as the traps tend to draw sharks.

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We have fish traps in this area that are particularly nasty. Nets laid in the water and left there to trap fish. Near the surface there's a line between floats which I describe to crew as "big red balls." They seem to know what I mean. Between the balls one can be confident there's a line taut enough to wreak havoc.

 

I've experienced this once, in the waters between the Sakonnet and East Passage in RI Sound, to those in the know.

 

I freaked out. I knew I was tempting fate but I missed the trap. As we went over I watched the line below the water trace my bottom. A gradual slope down as it went under the keel, "fell up" quickly off the keel. Rudder next. I held my breath as the line hit the leading edge. Felt and heard an underwater "twang" as the line caught the spade rudder and made it under. Somehow. We carried on.

I stay offshore at least a few miles when transiting between Sakonnet and Brenton Pt for that reason. Those traps are not marked and their positions change. And if you do get caught it is not advisable to jump out to clear the line as the traps tend to draw sharks.

 

 

I do now. I should not have cheated it.

 

I've always assumed where there are no seals there are no sharks, but your point is a good one. I wonder if we'll see seals in the bay at some point. A few years ago we sailed S of the Vineyard near No Mans Land to do something different to sail to Nantucket. Zillions of seals, and everything uncharted because of the breach at Katama, which seems to be filling in now, but I've never had a good experience in Edgartown. Give me Lake Tashmoo or Oak Bluffs.

 

shark-seal-lure_1890783i-620x620.jpg

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We have fish traps in this area that are particularly nasty. Nets laid in the water and left there to trap fish. Near the surface there's a line between floats which I describe to crew as "big red balls." They seem to know what I mean. Between the balls one can be confident there's a line taut enough to wreak havoc.

 

I've experienced this once, in the waters between the Sakonnet and East Passage in RI Sound, to those in the know.

 

I freaked out. I knew I was tempting fate but I missed the trap. As we went over I watched the line below the water trace my bottom. A gradual slope down as it went under the keel, "fell up" quickly off the keel. Rudder next. I held my breath as the line hit the leading edge. Felt and heard an underwater "twang" as the line caught the spade rudder and made it under. Somehow. We carried on.

I stay offshore at least a few miles when transiting between Sakonnet and Brenton Pt for that reason. Those traps are not marked and their positions change. And if you do get caught it is not advisable to jump out to clear the line as the traps tend to draw sharks.

 

 

I do now. I should not have cheated it.

 

I've always assumed where there are no seals there are no sharks, but your point is a good one. I wonder if we'll see seals in the bay at some point. A few years ago we sailed S of the Vineyard near No Mans Land to do something different to sail to Nantucket. Zillions of seals, and everything uncharted because of the breach at Katama, which seems to be filling in now, but I've never had a good experience in Edgartown. Give me Lake Tashmoo or Oak Bluffs.

 

shark-seal-lure_1890783i-620x620.jpg

 

If that was the seal in my avatar, his luck must have ran out.

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We have fish traps in this area that are particularly nasty. Nets laid in the water and left there to trap fish. Near the surface there's a line between floats which I describe to crew as "big red balls." They seem to know what I mean. Between the balls one can be confident there's a line taut enough to wreak havoc.

 

I've experienced this once, in the waters between the Sakonnet and East Passage in RI Sound, to those in the know.

 

I freaked out. I knew I was tempting fate but I missed the trap. As we went over I watched the line below the water trace my bottom. A gradual slope down as it went under the keel, "fell up" quickly off the keel. Rudder next. I held my breath as the line hit the leading edge. Felt and heard an underwater "twang" as the line caught the spade rudder and made it under. Somehow. We carried on.

I stay offshore at least a few miles when transiting between Sakonnet and Brenton Pt for that reason. Those traps are not marked and their positions change. And if you do get caught it is not advisable to jump out to clear the line as the traps tend to draw sharks.

 

 

I do now. I should not have cheated it.

 

I've always assumed where there are no seals there are no sharks, but your point is a good one. I wonder if we'll see seals in the bay at some point. A few years ago we sailed S of the Vineyard near No Mans Land to do something different to sail to Nantucket. Zillions of seals, and everything uncharted because of the breach at Katama, which seems to be filling in now, but I've never had a good experience in Edgartown. Give me Lake Tashmoo or Oak Bluffs.

 

shark-seal-lure_1890783i-620x620.jpg

 

Never been in Tashmoo but don't really like Vineyard, prefer Cuttyhunk or Nantucket

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Tarpaulin Cove is another good alternative to the Vineyard. Ever been there?

 

Here's Quail with Tarpaulin Cove Light in the background.

 

Jody31_zps69b5c4a6.jpg

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Rasper and I are whacking away at the new cutter.

 

I had sketched in an outline for where I thought the ballast would go. I figured 14,000 lbs. of outside lead. But I blew it. I was 280 lbs. off with my sketch. That's a W.A.G 2% error. I had better tighten things up.

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Not "slacking off" Flash. I worked hard on Saturday so I went easy on myself on Monday. But if it makes you feel better I have been here working since 2am this morning. I woke up with ideas that I wanted to get onto acad before I forgot them.

I think I'll g back to bed now.

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Rasper and I are having fun bringing this new design to life. Tomorrow I go to the builder with the client to make some important decisions regarding construction method.

This is an early rendering with many details left to be worked out but we are getting there.

Aft%20quarter%203D%202_zpsvpmjda3s.jpg

Bow%20quarter%203D_zpsqgycqdcq.jpg

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Wow, the renderings really bring the design to life. It looks very very purposeful.

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Rasper and I along with the rest of the significant parties just spent 2.5 hours on Skype on this new project. Looks like a go. Next step is a meeting of the minds at my shack.

The fun never ends!

PSC%2063%20raised%20salon%20C%201-27-15_

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I can't wait to see the renderings for this. To my untrained eye this boat is so00 sweetly proportioned. I want one but the lottery gods are not cooperating.

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Thanks Olaf. Will you write a letter saying so to the IRS for me. I'm sure they'll take notice.

 

Py;

Do you mean the PSC 63 or my new "you talkin' to me?" cutter?

Rasper has been hard at work trying to make sense out of my 2D drawings. He's getting the hang of it.

PSC%2063%202-18-15_zps5zdhgvbl.jpg

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Matagi:

Correct. I drew several sheers and finally settled on one that was non planar. Of course it could change but I was not getting the look I wanted with a planar sheer. I have never been married to planar sheers. They are just one way of doing it. LFH's TICONDEROGA has one of the best sheers ever and it's way off planar.

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Thanks Olaf. Will you write a letter saying so to the IRS for me. I'm sure they'll take notice.

 

Py;

Do you mean the PSC 63 or my new "you talkin' to me?" cutter?

Rasper has been hard at work trying to make sense out of my 2D drawings. He's getting the hang of it.

PSC%2063%202-18-15_zps5zdhgvbl.jpg

Bob. I was talking about the PSC 63 raised saloon cutter. It just looks right to me. I'm in lust.

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It's a beauty, Bob. Classic Perry lines and the rubrail looks classic PSC as well. Lust is just.

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Thanks a lot.

 

Kind of excited about the meeting with the client and Jim Betts this morning. Rasper has been slaving away to get the 3D model as far along as possible. This morning is the time for the big push to do the 43' cutter is all carbon fiber. This is a big decision. I'm pretty certain that it will be the first "traditional" boat ever built in all CF.

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On that type of boat will going all carbon actually do anything other than satisfy the client (and reduce his bank balance)?

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I'm going to pretend that I understood Bob. Displacement is determined by the underwater volume. He needs a certain weight to get that immersed volume. If he gets to build the structure (and mast?) out of carbon, he'll be able to add more lead for that given immersed volume. If I am right, more ballast for a given displacement means a stiffer boat, and other good things.

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If it's a drifter kind of day, any weight you can get out that isn't doing work is good, IMO.

Like the Chesapeake or Lake Michigan a lot of the time.

If it's a drifter kind of day, I thought that the main issue would be wetted surface.

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Mmm, yes but I'd think if you could put that weight down low it would allow you to put a bigger stick up, and would result in major pluses for light air as well as stiffness.

 

Bob will straighten us out and tell us.

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New Design

 

I completely agree with the clients choices below the waterline. With so many boats having been abandon or sunk due to rudder issues and the ability to get a custom design cruiser why not go this way? The client can then have Bob and Betts work some magic to squeeze out performance from so many other areas. Every week it seems we have another story about a rudder issue. More often then not the boat is abandon. Either create a separate watertight compartment for inboard rudders or go this way. Looks like both Tanton and Perry are ready for clients who don't want to become Chinese Freighter crew!

 

To the client: Thank you for allowing Bob to share the design process. That boat is gorgeous!

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Yes.

Yes.

Yes.

Yes.

Yes, kind of although there are some limits on just how tall a rig you can put over a boat.

You are very welcome and thank you.

 

Just got back from the yard. Very good meeting with some major decisions made.

Boat will be carbon fiber hull and deck

Hull will be painted

Decks will have teak overlay

Hull and deck built over male molds

Ballast will be internal lead

No faux timber stem detail

No faux nothin

Bow sprit will be carbon.

Leaning towards Beta engines (thanks to Gate's diligent research)

 

This will be a unique cruising boat and the good news is the yard is exactly one hour from my shack so they can expect me and Ruby frequently. Jim Betts is a very creative guy who has built a lot of boats and I'm looking forward to working with him and his son Kellen very much. I'm going to have some fun.

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It's gung hay fat choy here as well.

Happy year of the sheep to everyone.

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Goat!

Goat!

Goat!

 

 

sheesh!

 

I get weird requests. Just got an email tonight asking me to design a high speed, power trimaran

"Hang on, I'll connect you with the high speed trimaran department."

dingadingadinading, ,,,,,,,,,,,,,,,,,,,

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Goat!

Goat!

Goat!

 

 

sheesh!

 

I get weird requests. Just got an email tonight asking me to design a high speed, power trimaran

"Hang on, I'll connect you with the high speed trimaran department."

dingadingadinading, ,,,,,,,,,,,,,,,,,,,

How about a reasonable speed (16-18 knot cruise) displacement power cat? Say 30'x10' and very light weight and simple? Do you have a power cat department?

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Goat!

Goat!

Goat!

 

 

sheesh!

 

I get weird requests. Just got an email tonight asking me to design a high speed, power trimaran

"Hang on, I'll connect you with the high speed trimaran department."

dingadingadinading, ,,,,,,,,,,,,,,,,,,,

How about a reasonable speed (16-18 knot cruise) displacement power cat? Say 30'x10' and very light weight and simple? Do you have a power cat department?

 

Kim, I know that you have a specific requirement for such a boat, but it strikes me as a recipe with much wider application. A few months ago I did some searching to see what was available, but the closest I found was still some distance away.

 

It's odd that this niche remains empty, because it's quite a big niche.

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Goat!Goat!Goat! sheesh! I get weird requests. Just got an email tonight asking me to design a high speed, power trimaran"Hang on, I'll connect you with the high speed trimaran department."dingadingadinading, ,,,,,,,,,,,,,,,,,,,

How about a reasonable speed (16-18 knot cruise) displacement power cat? Say 30'x10' and very light weight and simple? Do you have a power cat department?
Kim, I know that you have a specific requirement for such a boat, but it strikes me as a recipe with much wider application. A few months ago I did some searching to see what was available, but the closest I found was still some distance away.It's odd that this niche remains empty, because it's quite a big niche.

I think so, but just like the Sliver design I have looked all over the place and not found anything very close to what I envision.

 

I must have eclectic taste in boats.

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Goat!Goat!Goat! sheesh! I get weird requests. Just got an email tonight asking me to design a high speed, power trimaran"Hang on, I'll connect you with the high speed trimaran department."dingadingadinading, ,,,,,,,,,,,,,,,,,,,

How about a reasonable speed (16-18 knot cruise) displacement power cat? Say 30'x10' and very light weight and simple? Do you have a power cat department?
Kim, I know that you have a specific requirement for such a boat, but it strikes me as a recipe with much wider application. A few months ago I did some searching to see what was available, but the closest I found was still some distance away.It's odd that this niche remains empty, because it's quite a big niche.

Have you checked-out Chris White's power cats? http://chriswhitedesigns.com ?

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Goats, Sheep, to some they are all the same.

 

Never the less, I stand humbled and corrected

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Judging by the number of posts I've read eg: http://www.ybw.com/forums/showthread.php?420653-Beta-engine-heat-exchanger&highlight=beta+heat+exchanger The Beta is prone to heat exchanger problems.

 

My slip neighbour fitted a Nanni. Same Kubota base engine, but different marinizing bits. Maybe worth a look.

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