soma

Gunboat 68

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DCN, google "Smythe Hybrid Wing" ... this has some cool potential to instantly wind-vane with the sheet released, and also seems to have some of the flap functionality you mention.
Example links:
https://www.boatdesign.net/threads/hybrid-wing-sail-used-by-randy-smyth-to-win-everglades-challenge.59514/ 
https://www.fastforwardcomposites.com/hybrid-wing

It'll be interesting to see how these concepts scale and tests... exciting times ahead. Better wings, sails, headboards, and creative techniques for using them.

My boats are WAY lower tech than Gunboats or the FFC fleet, but I'm looking forward to what trickles down.

Randii

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15 hours ago, mpenman said:

Can you please provide examples that you like. Performance (cruising) is what I'm most interested in.

Power winches aid in doing things quicker without having to grind, they don't change the fundamental method of reefing.

As a caveat my preferred reefing is still slab reefing with strops on both the clew and tack, although I will admit to liking antal blocks on the main with a jammer when sailing at night. I don't like going up/back to put a strop on the clew at night...….with the block you remove some of the chafe associated with throwing in a reef.

I'm interested too.

The tack is easy enough to secure. The clew is another story, especially without sending someone to the end of the boom on the roof.

Here is an example of a Karver lock on the Rapido 60 (that one is for the headsails, but same principle on reef lines):

https://youtu.be/RHzBQYG0Dtk?t=87

These hooks aren't cheap however. I also worry about reliability. Anybody here has used them regularly for a long time?

On the same boat, they use Karver reef hooks:

https://youtu.be/RHzBQYG0Dtk?t=122

I have never used these hooks, if they work well it seems like a good solution.

The most common solution may be to use clutches on/in the boom. Below are two examples, the first image is a 60+ foot Catana, the second one shows clutches with remotes on an early Gunboat 66.

reef.JPG

IMGP4674.JPG

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Hooks are reliable. They work at the tack so why not the clew? Big clutches are also generally reliable. Those Spinlock remote triggers? Nice concept but personally I would pass, they work well initially but over time the spring force weakens, i.e they would be a yearly replacement item or possibly even semi-annually. Of course a normal cleat would also work in that instance and it does save having to climb out to the back of the boom. My biggest issue with slap reefing isn't the difficulty or time nor crew requirements but the fact that water gets trapped in the slabs when reefed for days on end on wet boats. This has been a real issue for serious offshore race boats for time now, though Gunboats are quite a bit drier than a wicked up VO65 or 70.

@Wess, if you need a hand shoot me a PM. I won't claim to be an expert but I am involved in the design of high efficiency chargers and various EE bits on a regular basis..handy with a multimeter and will work for beer.

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4 hours ago, Whiskey.T said:

Here is an example of a Karver lock on the Rapido 60 (that one is for the headsails, but same principle on reef lines):

https://youtu.be/RHzBQYG0Dtk?t=87

These hooks aren't cheap however. I also worry about reliability. Anybody here has used them regularly for a long time?

Oops, I said "hooks", but I meant "locks".

4 minutes ago, samc99us said:

Hooks are reliable.

Yes, hooks are nice. My question was really about locks. I have never seen them on reefing lines, only on headsail halyards, but I know they are used there sometimes.

I agree with you about remote triggers.

As a side note, I just saw a different kind of remotely operated clutch, I don't know what it's worth:

 

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Posted (edited)
13 hours ago, Whiskey.T said:

Oops, I said "hooks", but I meant "locks".

Yes, hooks are nice. My question was really about locks. I have never seen them on reefing lines, only on headsail halyards, but I know they are used there sometimes.

I agree with you about remote triggers.

As a side note, I just saw a different kind of remotely operated clutch, I don't know what it's worth:

 

Reef locks for the clew are very position and orientation critical, it also means that the mainsail design is basically locked in unless a new boom is built (or heavily modified). The locks have been sort of standard on monohulls such as the Volvo boats (but also TP52s, Maxi 72s and superyachts). I know a couple of superyachts changed over about 6/7 years ago from the hooks to locks as the design wasn't nearly as evolved as the hooks are now. The reef locks are really no different from the stuff the various rig builders put in the mast, so a bullet spliced onto the reef clew line and a flipper, sheave and load bearing pins in the boom with a spring and trip line to operate the lock (unless you had the Hall AutoLock like the Gunboat 90 and Gunboat 55s which did away with the trip line). The reef hooks (as discussed in the rapido video) are available from a number of brands (Karver, Facnor, KZ I believe) and have various advantages over locks:

  • less moving parts
  • externally mounted so visible (assuming the coachhouse doesn't block your view)
  • attached using a lashing so position can be adjusted (within reason) during seatrials when the sailmaker didn't get the webbing in the correct spot or was late in supplying the reef dimensions to the builder of the boom
  • the fitting itself is usually lighter than a lock with flipper/spring/housing/bullet
  • easier to maintain

Some downsides:

  • External so you have a bit of stainless/titanium/aluminium flying around at points
  • there is the possibility of the hook getting caught on the lazy-bag/webbing on the boom or on the foot of the main thus making life quite difficult when you try to reef at 3am
  • Depending on attachment the total system weight (doublers, fasteners, lashings, additional strengthening laminate, patching) can be higher than total lock assembly
  • requires 2 lines for each reef position (1 to hook, 1 to unhook with unhook higher loaded than a classic lock trip-line)

I have seen the hooks on various HH55, HH66 and the Rapido 60, believe they might have been for the gb68 as well but not sure.

Finally, the remote operation of jammers: the Karver jammers require you to pull 1 trigger to close and 1 to open. There are pros and cons to the system (3 "jaws"and quite high load capability definitely pro, but width a definite con). Never worked with the Spinlock remote, only with "custom" remote triggers and didn't experience any issues with those: looking after your gear is the most important factor.

Edited by lostmydetailsagain
small correction
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The remote Spinlock xx0812 is fantastic. On a big GB66/68 the xx0812 is too small but on my 55 project it's fine. Single line to release, spring engages it. 

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Yeah. Constrictors are cheap and easy, but slippage is a problem (especially in low visibility/low access areas like the back of a boom).

The xx is a perfect mousetrap. They're not cheap but they're not outrageous either. I think the xxc is good for up to 2.6t. Our mainsheet load is approx 4 tons, reef lines are 2:1. We'll go to full hull fly at first reef, but 2nd reef onward is likely twisty and de-powered, so well shy of full RM. The only time I've had issue with an xx is either running a 14mm line in a 8-12mm clutch, or when tape gets jammed in there. 

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But back to the topic at hand...looks like Condor is trucking from the Canaries. She should make it to St. Barth's before Les Voiles. Apparently they don't plan to race (understandably) but it'll be great to see her in person. Hopefully they rumble through the fleet. 

IMG_6637.PNG

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We use constrictors on a lot of high load situations.

No case damage, no slippage at all (cases need to be milked though so you need easy access to them)

Rope needs to be good quality, exact diameter. You can not use doublebraid in constrictors as it stretches,gets smaller and slips.

Being able to quickly release them under full load is a bonus.

They are not good on kite halyards. (Too much drag)

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On 4/1/2019 at 2:55 PM, dcnblues said:

That's a pretty absolute statement on me being wrong. Please list how many world record fast multi-hulls you have crewed. I've sailed ORMA 60's and other large multis I have had before and currently own a performance 40fter  as well as being involved in current VO70 and 100ft Comanche mono's.......The subject is a fast new state of the art multi-hull. And record breaking multis.... If it were designed the way boats have been in the past, there'd be nothing to talk about in this topic. New tech opens up new possibilities. Put me down for 20 bucks. I absolutely think designers and teams shooting for world records will consider easier reefing systems as a selling point when going to potential sponsors. Nobody likes losing a bid for a world record to a capsize. And it happens all the time It happens very rarely and mostly due to breakages (like float with Groupama of NZ) but you may tell me all the others......, or have I just read more interviews about this subject than you? The systems they are using are easy, simple systems that work and allow a boom 50% (not sure) lighter than existing furling booms. I'm big on not having a swinging bit of heavy boom over my head... but that's me.

I've mentioned this before and I think it's worth discussing: I've done enough racing to speculate about a macho racer ethic and culture where even among crew members, it's considered wussy to suggest slowing the boat down Armature club racing maybe . I think the ethic often is that with trimmers on station, pushing wind limits for the existing sail plan is no big deal even when seriously overpowered for conditions. And one is also a wuss if one suggests that slowing the boat down will reduce the chances of major breakage which will take the boat out of the competition. It is largely written off as part of racing. I'm not sure of your experience as ALL the programmes I'm involved in use cross over charts on what sails to use at what angle in what wind speeds and these charts are followed to within 1-3 knots variations  for timed periods. There is no such thing as being a "Wuss". This is done for absolute speed / efficiency / VMG and saftey....Many 1000's of hours go into these cross over charts.   But absolutely and especially for single handed racers, I think the best technology available in the next few years will be an easy sell to a corporation that is going to put its name on a boat and hire a skipper who has possibly already pearled/pitch-polled one race boat. When you dismiss the exhaustion of ocean racers and push existing reefing systems as easy to use in, say the southern ocean or maybe North Atlantic, then I'm not the one who seems uninformed.

Newer systems integrating a rotating mast with cars and a boom furler will indeed allow fine tuning for conditions that will be a distinct advantage over current systems. (As I keep saying though, it would be really great to have better data on the weight penalty percentage). Bingo.... this has been and is the issue IMHO.... But regarding weight, new race boats are already pushing the limits of carbon fiber tech. I don't consider the extra weight for a rotating mast w/ boom furler all that significant in the big picture. On my race boat, 100kg makes a difference when the boat weighs 3000kg but more so reefing is easy as is...I'm also not really versed enough in aerodynamics to speculate, but a lot of aircraft use slotted flaps to increase performance. Computers may show some advantage there from the laminer flow of an over-rotated mast  compared to a stock unrotating mast creating turbulence over the sail. 

We disagree on the difficulty of adjusting a boom's angle (which is what, one crank in or out on a topping lift? Topping lift.... Who uses that...? Good crews coordinate clew end with tack end or maybe lazy jacks... I haven't seen a dedicated topping lift on a race boat in years...) to crew(s) who are really short on sleep. And on the potential of engineers to keep improving and integrating these boom / sail / mast systems. I keep going back to aircraft wings. I see the combined system as faster than the lighter conventional system. And that will be an easy sell to the buyer of an expensive Gunboat.

*Caveat: I don't pretend to have any training or special knowledge of aerodynamics. I'm well aware of how almost infinitely complex is the mast to sail(s) system. But I would also like to point out that I'm not aware of any one company who is integrating the design of a furling boom, a mainsail, a low friction track system, and a rotating mast. Frankly, I see a market vacuum there. But what do I know?

My response in red above.... I'm not having a go or trying to big note. I just don't agree on boom furling for the boats discussed here.

On 4/1/2019 at 1:32 PM, mpenman said:

Can you please provide examples that you like. Performance (cruising) is what I'm most interested in.

Power winches aid in doing things quicker without having to grind, they don't change the fundamental method of reefing.

As a caveat my preferred reefing is still slab reefing with strops on both the clew and tack, although I will admit to liking antal blocks on the main with a jammer when sailing at night. I don't like going up/back to put a strop on the clew at night...….with the block you remove some of the chafe associated with throwing in a reef.

 

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that's a cool system for reefing.. I like it. :)

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15 minutes ago, Keith said:

that's a cool system for reefing.. I like it. :)

I like the look as well.... it's like having Halyard / boom locks... takes all the compression loads out

I know of one guy using it and he is happy ATM 

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5 minutes ago, PIL66 said:

I like the look as well.... it's like having Halyard / boom locks... takes all the compression loads out

I know of one guy using it and he is happy ATM 

Yup, they remove the need to add a strop, but that being said, you now have 6 lines for 3 reefs. I'm still preferring an antal block on the main (heavier perhaps yes) with the ability to use both a clutch and a winch to secure. As @lostmydetailsagain noted, there are pros and cons to each system. The more I overthink it, the more I 'harken' back to the current system I use.

What I do like about the hooks is the ability to set the clew at the exact position each time without having to mark a line which is nice.

I'm becoming a fan of the constrictors, just not in/on the boom for reefing. 

Back to topic

@soma how is Condor doing speed wise on the trip over...……….not that speed is important......:D

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How often do you need to replace that strop on the clew - I would imagine that there is some chafe from the reef tensioning line running through it?  Or on a boat like this is the lifespan of the sail short enough that you don't have to worry about it?  Or am I overthinking it, and you just replace that strop every 10,000 miles or something?

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57 minutes ago, mpenman said:

Yup, they remove the need to add a strop, but that being said, you now have 6 lines for 3 reefs. I'm still preferring an antal block on the main (heavier perhaps yes) with the ability to use both a clutch and a winch to secure. As @lostmydetailsagain noted, there are pros and cons to each system. The more I overthink it, the more I 'harken' back to the current system I use.

What I do like about the hooks is the ability to set the clew at the exact position each time without having to mark a line which is nice.

I'm becoming a fan of the constrictors, just not in/on the boom for reefing. 

Back to topic

@soma how is Condor doing speed wise on the trip over...……….not that speed is important......:D

The 3 lines needed  are way smaller than normal lines and the 3 other Trip lines are tiny... Actually could save weight...

Pros are are much better loading.... I have constrictors now ... They need to be the perfect diameter and even then I've installed cleats as a safety... I'm not convinced.

22 minutes ago, hdra said:

How often do you need to replace that strop on the clew - I would imagine that there is some chafe from the reef tensioning line running through it?  Or on a boat like this is the lifespan of the sail short enough that you don't have to worry about it?  Or am I overthinking it, and you just replace that strop every 10,000 miles or something?

All Strops should have proper chafe guards... If that's done they will outlast the sail plus how often are you reefed..?

 

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13 hours ago, mpenman said:

I'm still preferring an antal block on the main (heavier perhaps yes) with the ability to use both a clutch and a winch to secure.

Yes, a block is nice. It eliminates chafe issues and makes it much smoother to reef downwind when you need to keep some tension on the clew so that the mainsail doesn't chafe on the spreaders (this is a problem I have).

But then you need the clutches on/in the boom. You mention leaving the reef line on a winch, but where is the winch? I can't tell from your avatar what boat you sail (not a GB68), but I imagine that the winch is in the cockpit. That means that the reef line goes from the boom to the block, back to a sheave at the end of the boom, through the boom to another sheave, down through the deck to another sheave, aft to yet another sheave, to finally a clutch and a winch in the cockpit. (This is exactly what happens on a Catana, for example.) That's a lot of blocks and sheaves. That's a lot of compression on the boom and sheave boxes. That's a lot of stretch, noise, chafing, opportunities for disaster. Even if your winch is on the mast, there is a lot of compression on the gooseneck.

I have that system, so I understand the convenience at certain times. But when I know it's going to be blowing for a while, I secure the clew to the boom and then release a few inches on the reefing line (what is called a "cravatte" in French). This is great, it eliminates all the problems listed above (and the redundancy makes it extra safe), but it involves going up on the roofcoach to tie up a line at the end of the boom. When I do that I have a preventer on the boom, so there is little risk of the boom throwing me out, but the motion of the boat alone makes this a risky exercise.

A clutch in the boom eliminates some of these issues, but then you need a remote trigger.

Clutches on the boom is good too, but then you need someone to get to them. Depending on where exactly they are, it may or may not be better than a "cravatte".

Hooks are great, but kinda clunky and more lines, more friction. Still the best I can see.

Locks seemed ideal to me but @lostmydetailsagain mentioned some issues I wasn't aware of (they require perfect angle, etc.). And they are very expensive.

Like you and other have said, pros and cons to everything...

What does the GB68 use? Hooks, locks, something else? I know at least the first two hull numbers of the 66 series (Kanaloa and Sugar Daddy) used clutches with remotes set near the gooseneck.

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I like the hook - does it reliably hook up when the main is flogging and shit is happening at 3am?

How do you unhook however without a person's hand getting in the picture.

 

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7 minutes ago, Zonker said:

How do you unhook however without a person's hand getting in the picture.

It seems like it's got nowhere to go but in the hook as long as you have tension on the "hooking" line.

The video above shows the other line that swings the hook back on itself until it releases (like a trip line on an anchor). I assume you have to ease the tension on the hook to be able to un-hook it  but I don't see any reason why you would need to go up there (and presumably things are a bit quieter when you are taking the reef out!)

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1 minute ago, Airwick said:

It seems like it's got nowhere to go but in the hook as long as you have tension on the "hooking" line.

The video above shows the other line that swings the hook back on itself until it releases (like a trip line on an anchor). I assume you have to ease the tension on the hook to be able to un-hook it  but I don't see any reason why you would need to go up there (and presumably things are a bit quieter when you are taking the reef out!)

You loosen the main and pull the release line (the black one in the video).

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3 hours ago, Whiskey.T said:

What does the GB68 use? 

Condor has essentially got Southern spars (branded Hall for obvious reasons) bullet locks. Same thing as in the rig. There are pro's and con's for all options which are well summarised by others in this thread, as well as personal or owners preference. 

GB6802 will have a similar but different autolocks, but not a hook. 

For those saying clutches or jammers, nothing against that but honestly our loads are so huge and the line diameter and holding capabilities without slippage etc accompanied by the addional compression and carbon/patching required to handle said load drives us to locks. Purchases or clutches can be done, but we've done the math and our very clear answer is that not having locks is more expensive, heavier and frankly more dangerous. 

To be clear this is for a Gunboat 68, a big righting moment boat. You quickly get into a lot more options when you go smaller and lighter. 

Locks are a hot topic but I only have one opinion: they gotta work!!! I've seen huge improvements in reliability and usability in this arena over the past 5 years. Still work to be done, but getting there.

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Thanks @Greenflash, it makes perfect sense. The price of three extra locks is probably not an issue on a Gunboat and unlike hooks they don't require release lines.

One thing that worries me about halyard locks is that they wouldn't unlock when I need them to, but that is much less of a concern on reefing lines where you (supposedly) have access and you need them to unlock when the weather is getting better, not worse. And if you already have locks for the halyards, why not for the reefing lines.

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Played with the Karver hooks last weekend (just tested, not in reefing conditions). They work okay when hooking, although seems that hearing them click might be a bit hard in the proverbial 3am squall. To unhook you need to drop the main quite a bit, like 3 feet. They do add to some lines snagging when you raise the main, but manageable.

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14 minutes ago, EarthBM said:

Played with the Karver hooks last weekend (just tested, not in reefing conditions). They work okay when hooking, although seems that hearing them click might be a bit hard in the proverbial 3am squall. To unhook you need to drop the main quite a bit, like 3 feet. They do add to some lines snagging when you raise the main, but manageable.

Not sure about dropping the main for this to work... Well not on the boat I saw... we released the mainsheet only and pulled the trip line.

Halyard / boom bullet locks are awesome and in 6 years of racing with them, only once did we have a problem where we sent a guy up the rig to manually release a headsail.... Not a place i want to be in swell...

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On ‎4‎/‎4‎/‎2019 at 1:11 PM, Whiskey.T said:

Yes, a block is nice. It eliminates chafe issues and makes it much smoother to reef downwind when you need to keep some tension on the clew so that the mainsail doesn't chafe on the spreaders (this is a problem I have).

Being able to reef on all points without having to luff up is a good thing, especially when it's blowing and you're running on a broad reach with a following sea.

On ‎4‎/‎4‎/‎2019 at 1:11 PM, Whiskey.T said:

But then you need the clutches on/in the boom. You mention leaving the reef line on a winch, but where is the winch? I can't tell from your avatar what boat you sail (not a GB68), but I imagine that the winch is in the cockpit. That means that the reef line goes from the boom to the block, back to a sheave at the end of the boom, through the boom to another sheave, down through the deck to another sheave, aft to yet another sheave, to finally a clutch and a winch in the cockpit. (This is exactly what happens on a Catana, for example.) That's a lot of blocks and sheaves. That's a lot of compression on the boom and sheave boxes. That's a lot of stretch, noise, chafing, opportunities for disaster. Even if your winch is on the mast, there is a lot of compression on the gooseneck.

I have an Atlantic 57. My reefs are through the antal block, through a block in the boom, then to a clutch at the end of the boom. The line exits to a block on the end of the boom. I use a snatch block to a winch when reefing. I lower the main and use a winch to pull in the reef.. Reefing by it's very nature implies that we're a little over canvassed for current conditions. Only the Antal block then the boom block to the clutch so it's actually fairly little friction relatively speaking. I like the hook system, but I want to use it when it's  blowing 30 plus and it's just me. 

On ‎4‎/‎4‎/‎2019 at 1:11 PM, Whiskey.T said:

I have that system, so I understand the convenience at certain times. But when I know it's going to be blowing for a while, I secure the clew to the boom and then release a few inches on the reefing line (what is called a "cravatte" in French). This is great, it eliminates all the problems listed above (and the redundancy makes it extra safe), but it involves going up on the roofcoach to tie up a line at the end of the boom. When I do that I have a preventer on the boom, so there is little risk of the boom throwing me out, but the motion of the boat alone makes this a risky exercise.

Agreed. On our boat we have a main, traveler and preventers on the boom. No way I'm venturing out on the roof at night. My 'normal' crew is 6 kids (6-12) and my wife...…..hence my desire for as foolproof systems as possible, even if they're not the coolest. I'll do what you do in daylight, which is put a strop on the block to the boom, but keep the reef line in the clutch.

On ‎4‎/‎4‎/‎2019 at 1:11 PM, Whiskey.T said:

 

Like you and other have said, pros and cons to everything...

 

Yup, everything is always a compromise.:D

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On ‎4‎/‎4‎/‎2019 at 4:17 PM, Greenflash said:

For those saying clutches or jammers, nothing against that but honestly our loads are so huge and the line diameter and holding capabilities without slippage etc accompanied by the addional compression and carbon/patching required to handle said load drives us to locks. Purchases or clutches can be done, but we've done the math and our very clear answer is that not having locks is more expensive, heavier and frankly more dangerous. 

Not sure I agree with that 100%. Loads on the Atlantic 72 are pretty substantial and they tried constrictors and locks and ended up replacing the boom (albeit it busted in half) with clutches. That being said they use a strop on the clew most of the time. The constrictors I've used, when used with the right diameters of both the restrictor and line are pretty damn impressive. They can hold a serious, serious load. More than a clutch from what I have seen. 

On ‎4‎/‎4‎/‎2019 at 4:17 PM, Greenflash said:

To be clear this is for a Gunboat 68, a big righting moment boat. You quickly get into a lot more options when you go smaller and lighter. 

Locks are a hot topic but I only have one opinion: they gotta work!!! I've seen huge improvements in reliability and usability in this arena over the past 5 years. Still work to be done, but getting there.

As I have noted prior, I'm about doing it 100% single handed. This means a single person on watch can reef safely and quickly every time without having to worry about a single thing going south. Occam's razor is my favorite line for a boating problem...……

Still gotta congratulate you on that boat...……...one damn fine looking boat...…..

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On 4/3/2019 at 5:27 PM, PIL66 said:

-The systems they are using are easy, simple systems that work and allow a boom 50% (not sure) lighter than existing furling booms. I'm big on not having a swinging bit of heavy boom over my head... but that's me.

-I'm not sure of your experience as ALL the programmes I'm involved in use cross over charts on what sails to use at what angle in what wind speeds and these charts are followed to within 1-3 knots variations  for timed periods. There is no such thing as being a "Wuss". This is done for absolute speed / efficiency / VMG and saftey....Many 1000's of hours go into these cross over charts.

-Topping lift.... Who uses that...? Good crews coordinate clew end with tack end or maybe lazy jacks... I haven't seen a dedicated topping lift on a race boat in years...

-Can you go into this in a little more depth? I can't imagine there aren't some conditions where more weight in the boom wouldn't be, say, a stabilizing advantage. In gusty, light conditions that induce lifting / banging (especially on a front cockpit boat whose design precludes hydraulic vangs / struts? I'm also curious about whether ocean racers with crew ever set preventers (say in rough swells and conditions which make the accidental gybe a possibility). Are preventers enough of a hassle that racers never use them? I'm curious.

-...And then the tired crews at 3 in the morning look at the variable gusting winds and push the chart limits a bit because reefing would be inconvenient and slow the boat down. Or will you stipulate that never happens?

-The topic was adjusting the correct boom angle to roller furl properly. I think you just missed that connection.

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I really don't want to derail / go too off topic, but can someone give me the brief bullet points on why Stainless isn't a good build option for a fast multihull? I'm sure there are good reasons, I'm just not up on them and would like to understand the materials comparison with Carbon Fiber a little better: Sixty times cheaper

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dcnblues, you seem to be in the final stages of designing your breakthrough catamaran.  can you post some renderings?

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Not at all. Peter Johnstone's original brief has me well covered. I too think tea would taste better at 18 knots while the tea service doesn't even rattle. (And what's the general opinion here? Could one make a stainless GB68 for half price? It wouldn't be as fast because it would be heavier, but polished up it might look pretty good...)

The opposing viewpoint against doing thing the easy way can be well summarized by this pic: fast racing

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Cost. My link was about cost. Stainless apparently 1/60th the price of Carbon. So would, or would that not knock down the price of the boat? For a percentage hit of what - 10%? 40%? But there are probably other reasons it's a bad idea for a sailboat even if it works for a spaceship (metal fatigue, others?). I was just asking.

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Fatigue & crevice corrosion in an anoxic environment (below waterline) are both probably issues - probably could address to some extent with choosing the right alloy (like for prop shafts).

Much better to just go with Monel - think there were a couple of boats built that way 50 or 60 years ago that are still kicking around.

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1 hour ago, dcnblues said:

Cost. My link was about cost. Stainless apparently 1/60th the price of Carbon. So would, or would that not knock down the price of the boat? For a percentage hit of what - 10%? 40%? But there are probably other reasons it's a bad idea for a sailboat even if it works for a spaceship (metal fatigue, others?). I was just asking.

Actually very simple, carbon is about 3-4 times stronger at about 5-10 times lighter. Lighter boats go faster. 

Our next boat coming will be all C6

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1 hour ago, mpenman said:

Cost. My link was about cost. Stainless apparently 1/60th the price of Carbon. So would, or would that not knock down the price of the boat? For a percentage hit of what - 10%? 40%?

You must be trolling. But the performance hit would be at least 50%. Say in same conditions the Gunboat sails 12 knots; the steel boat sails at 6. The weight difference is that much.

 

Steel is strong and cheap. Stainless is slightly weaker than typical "mild steel" but is not nearly cheap.

Raw carbon fiber unidirectional / biaxial is probably about $25 / lb when bought in quantity. Epoxy resin is probably a bit less. Say a finished high end laminate is 60% carbon/40% resin. So maybe $24/lb. This ignores the cost of consumables like vac films, peel ply, breather etc.

Mild steel is about $0.40 - $0.50 /lb. Stainless steel is about $1.60 lb for 316 plate.   So 1/15th the cost?

But the labour costs and methods of fabrication are totally different. It's like comparing apples to cheese.

There is a reason nobody builds performance boats in steel at these sizes of boat. It's too heavy. And nobody builds in stainless steel because modern paints are very good at reducing corrosion in steel boats. Until about 100m aluminum is pretty much the material of choice; then steel starts to get more attractive.

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The smart money here is on ferrocement.  By far the cheapest per pound if only the idiots designing multihulls could get their heads out of their own asses.  

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1 hour ago, Zonker said:

You must be trolling. 

I assure you, I wasn't. I simply found the clip about SpaceX moving from carbon to stainless interesting, and was curious about the applications for something like the GB 68 (beautiful spaceship, beautiful catamaran). I really wasn't aware that stainless wasn't corrosion resistant under the water line, nor was I clear on how much stronger the carbon was than steel. I thought they were closer together, and I'm always curious about manufacturing. Thank you for your information, I found it all interesting. One thing you didn't mention is that stainless forms an oxidation layer much like aluminum, but in moving saltwater, that layer gets washed away and real corrosion happens (making it even less corrosion resistant than aluminum). I apologize for going off topic. 

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3 hours ago, Zonker said:

Raw carbon fiber unidirectional / biaxial is probably about $25 / lb when bought in quantity. Epoxy resin is probably a bit less. Say a finished high end laminate is 60% carbon/40% resin. So maybe $24/lb. This ignores the cost of consumables like vac films, peel ply, breather etc.

 

Agree with your logic re metal vs composite, but materials prices have dropped recently.  We pay $US27/kg ($13 per pound) for carbon,  $US8.50 per kg ($US4 per pound) for infusion epoxy and about $1/sq m (10c per sq') for bags, mesh and peel ply.  This is a single, light weight (4.4 ton, 60 footer) boat price.  Building multiple heavy boats like the G68 and Outremers, the price should be lower. 

Greenflash,  

What happens to the dagger boards and rudders when you hit a log, whale or semi submerged container at 20+ knots?  

Does someone sit on the lee bow to keep a lookout when flying the headsail on the boat in the ad at the top of the page?  

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Did somebody rename this thread "the good, the bad and the ugly?"  Or maybe its a full moon or???  :ph34r:

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3 hours ago, harryproa said:

Greenflash,  

What happens to the dagger boards and rudders when you hit a log, whale or semi submerged container at 20+ knots?  

 Does someone sit on the lee bow to keep a lookout when flying the headsail on the boat in the ad at the top of the page?  

A good question, thank you. 

Your first line of defence when you think there may be something you could hit is to go slow and raise the boards and the rudders up. Not many boats this size can boast a 1.2m (<4ft) draft. 

But I know you want the good stuff so I'll answer your real question:

There's so much crap out there it has become not a question of IF but unfortunately WHEN. Fortunately impacts are usually against small UFOS like logs. To protect against that the bows, boards and rudders have reinforced leading edges. The bow has solid carbon section and a decent amount of laminate. I believe this should save you from haul outs and repairs for small impacts. 

If you hit something at 20 knots though, that is a different story. Not a fun topic but worth planning for.

Some of the MM/IRENS boats have bow cavities, VPLP went full Ultim on our bow detail. They put solid composite  in stem and then the whole bow is solid foam, quite high density also, not expandable type stuff. It is deigned as a crumple zone to absorb a lot of energy. Also, the way we glue/laminate it to the hull means it can rip off without compromising the hull. And then if it does there's a watertight bulkhead on the front and back of the sail locker. 3 levels of defence before pumps come into play. 

Boards: Any engineer will tell you it is very hard to engineer for grounding loads, so they simply bomb-proof the Daggerboard cases. There is a solid carbon and UD detail that is - "rather robust!" 

The goal is to have the boards shear off rather than any damage to the bearing housing, which could be catastrophic. 

About lookout for objects: I will let the more experienced skippers comment on this. My opinion is that obviously you can't have someone on a bow all day and night, but you do your checks all over during your watch. Please note that some owners have a more cruising setup or even delivery sails with the foot higher so they can see under them more easily. Other than that you roll the dice like everyone else... Or invest in some fwd looking sonar/radar/lidar... Some interesting stuff out there recently. 

On this topic, have you guys seen the new B&G Halo radar which has close range object detection? 

Right now we are working with B&G to ensure that it and the satcomms domes don't interfere with one another (if on the two spreaders). We are monitoring a boat it has been installed on for feedback. 

If anyone has info on this it would be much appreciated! 

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I really liked the false foam bow detail on our boat. The hull laminate ended about 4" before the bow and flat is created where the laminate from each side overlaps. Then about 4" of solid foam was glued to the bow and shaped. That was glassed over. Hit two big enough logs to crush the foam just below the waterline. Crushed the sacrificial foam each time but the watertight bow was fine.

Damage before repairs (hit was about 7-9 knots; we weren't paying attention to the speed and it was 3 am). Very loud bang.

 

1damage-1.thumb.jpg.6264881af0750052b497afca6e19411b.jpg

Easy to fix at low tide (picture is from Chagos archipelago)

1damage-3.thumb.jpg.ecd492e5afe17d4453ba5aa94eb3f89c.jpg

Took a similar daggerboard hit at about 7-8 knots. Board had a solid wood core but you can guess the shape of the UFO. I'm thinking big log.

1damage-2.thumb.jpg.ccf925fd91a1f232755900fb68e519f2.jpg

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Re the s.s. building - Ok you weren't trolling. My apologies. I'm glad Harryproa can get such good deals with carbon and epoxy. 

S.S. is funny. If you have it immersed in saltwater and there is lots of dissolved O2 you won't get corrosion. But have a barnacle cover the surface for 6 months and you might get pits 2-4mm deep! 

 

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On 4/7/2019 at 8:53 AM, dcnblues said:

-Can you go into this in a little more depth? I can't imagine there aren't some conditions where more weight in the boom wouldn't be, say, a stabilizing advantage. In gusty, light conditions that induce lifting / banging (especially on a front cockpit boat whose design precludes hydraulic vangs / struts? I'm also curious about whether ocean racers with crew ever set preventers (say in rough swells and conditions which make the accidental gybe a possibility). Are preventers enough of a hassle that racers never use them? I'm curious.

-...And then the tired crews at 3 in the morning look at the variable gusting winds and push the chart limits a bit because reefing would be inconvenient and slow the boat down. Or will you stipulate that never happens?

-The topic was adjusting the correct boom angle to roller furl properly. I think you just missed that connection.

"Can you go into this in a little more depth? I can't imagine there aren't some conditions where more weight in the boom wouldn't be, say, a stabilizing advantage."

I think this comment above and you wanting to build a stainless boat will do me..... I'm out

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@Zonker those images are pretty epic. Beaching the boat to do a repair in Chagos sounds like an adventure worth remembering. The crash bow did its job. Nice work. 

Personally I think a hungry shark just took a bite out of your board, how perfect is that shape? :lol: 

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Interesting build doc I saw on the t.v. I believe the boat is Black Pearl, steel, not sure what kind or how thick the steel is but the boat has lots of interesting details and is made to sail fairly fast, though not nearly as fast as the narrator was claiming.  He was saying it was built to set records but that must be hyperbole.  There must be some size where steel becomes better than other materials.  

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14 hours ago, Zonker said:

I really liked the false foam bow detail on our boat. The hull laminate ended about 4" before the bow and flat is created where the laminate from each side overlaps. Then about 4" of solid foam was glued to the bow and shaped. That was glassed over.

This is a 35' Shuttleworth catamaran with starboard bow tip sheared off by another boat that broke loose and dragged against it in a Kauai winter storm, shearing off one of the bridle lines (replaced in the pic).  No structural damage or penetration of the foam core hull.

Malihini007.thumb.JPG.039077645ace50d991a1343907532253.JPG

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On 4/6/2019 at 9:52 PM, Rasputin22 said:

Just build your dream catamaran in Titanium. SS is so last millenium...

as the one being build at the betts yard right now as we speak...

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4 hours ago, mundt said:

There must be some size where steel becomes better than other materials.

Yes, about 130m is about the upper limit on where aluminum power vessels are right now. That's the current state of the art. But 15 years ago a 100m aluminum vessel was the biggest...I think the current biggest is the 127m trimaran Littoral Combat Ships. Lots of aluminum fast ferry catamarans in the 100+ m range.

 

The biggest GRP boat I know of is Mirabella V at 75m. The Swedish Visby carbon fiber corvettes at 72.7 m are probably second. Flexibility and cost start to be significant drivers that lead you away from composites as you get bigger.

10 hours ago, Greenflash said:

Beaching the boat to do a repair in Chagos sounds like an adventure worth remembering

That was an easy one. Just 1 tidal cycle. Though you can't see the old stone pier right beside our hull and the pretty narrow beach. 

Also in Chagos - fixing the rudder on a 48' mono after they drifted onto a reef. We ballasted the bow down to get the rudder stuffing box above the waterline, took the rudder ashore and fixed it. 5 days from start to rudder back in the boat, with a fresh coat of antifouling. Not sure most yards would have been any faster. I was proud of that effort.

http://maiaaboard.blogspot.com/2015/06/aground-part-3-exotic-repairs.html

 

2 hours ago, ProaSailor said:

This is a 35' Shuttleworth catamaran with starboard bow tip sheared off by another boat that broke loose and dragged against it in a Kauai winter storm

That's exactly how our bows are constructed. We actually had our bows damaged in virtually the same way, by another boat that broke it's mooring lines at our dock and ended up across our bows too. That boat was a heavy 45' sailboat that also did in our forward crossbeam

 

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8 hours ago, Zonker said:

You must be really proud of your daughter. It seems like she took full advantage of your RTW cruise and she wrote about it well. I'm envious that you got to go to Chagos. I've heard lots about it from my buddy who sailed there on a boat named Lorcha, a 30' steel junk.

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Chagos is wonderful but the anchorage is a bit dangerous for the unwary.

The blog is my wife's work actually (misleading blog name I know). She writes professionally. Here's an article she wrote about the dispossessed Chagosians   http://www.bbc.com/travel/story/20151203-an-exiled-island-turned-private-tropical-paradise

I'm very proud of my kid. Last fall she was the "Campaign Coordinator" for a woman running for Mayor of Vancouver. She is now finishing high school doing an international baccalaureate at a United World College in Swaziland (Africa). She's a good writer too. At one point on our trip she wrote a 100,000 word novel - just because she wanted to

Her latest very poignant blog entry http://maiaabroad.blogspot.com/2019/03/exacerbated-by-distance.html 

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38 minutes ago, Zonker said:

Very poignant? 

"Last night I found out that my father has cancer."

Oh man. I don't know you other than from your contributions to this forum (great ones, by the way), but I do hope you are OK. You seem like a great father, husband, or friend. I don't know what else to say, so get well.

 

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Thanks. The prognosis is good at least for now. Canada's healthcare system might seem slow (hip replacements, cataract surgery), but when you get a cancer diagnosis it moves into high gear. I've had more CAT scans, MRI, and various types of anal probing than a National Enquirer alien abduction victim. When the last ultrasound showed minimal invasion of the colon wall things got less hectic. I was also rather relieved that my priority seemed to have dropped.

I really like her writing. She's a great kid and writes with a maturity beyond her years (she is 17).

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Good to hear.

Good to hear too that you haven't lost your sense of humor. :D

Yeah, she's seems like a smart kid with a good heart.

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Best wishes for the battle,  had a brief 'mini' version that probably doesn't even count but nevertheless....

Makes one glad that they did some of the bucket list early in any event....

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No kidding. Nobody gets out of here alive. 

"Enjoy every sandwich" - Warren Zevon 

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I'm glad that you shared the news. Even though we never met, I feel some kind of kinship. Partly it's the way you did your trip around the world in a modest boat and partly it's the way that you share your knowledge. I'm going to forward your wife's article on Chagos to my buddy who had such a memorable time there. 

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On 4/4/2019 at 10:17 PM, Greenflash said:

Condor has essentially got Southern spars (branded Hall for obvious reasons) bullet locks. Same thing as in the rig. There are pro's and con's for all options which are well summarised by others in this thread, as well as personal or owners preference.

...

Locks are a hot topic but I only have one opinion: they gotta work!!! I've seen huge improvements in reliability and usability in this arena over the past 5 years. Still work to be done, but getting there.

Had two locks side-by-side a couple of months ago, from before the North take-over. They were basically the same locks back then already. I thought it was funny how they had managed to find a very similar solution to the same problem :)

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https://www.marinetraffic.com/en/ais/details/ships/shipid:5855808/mmsi:339762000/vessel:CONDOR

As of April 5th, she was  25.09934° / -30.14606°

Oddly it says that she's headed NNE at 29 degrees? Must be an error.

Who want's to bet on the date and time of landfall? Extra credit if you know the destination. 

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I'm saying arrival in SXM in two days. A quick reset then off to Les Voiles to be seen but not race. Unless there's an extensive breakdown list, then they'll stay in SXM. 

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On 4/9/2019 at 3:36 AM, Zonker said:

Yes, about 130m is about the upper limit on where aluminum power vessels are right now. That's the current state of the art. But 15 years ago a 100m aluminum vessel was the biggest...I think the current biggest is the 127m trimaran Littoral Combat Ships. Lots of aluminum fast ferry catamarans in the 100+ m range.

your basic numbers are right but dates off. Stena built their 126m cats in the mid 90s.

At Austal we were working on the tri-hull that eventually became Benchijigua Express and the Littoral combat ships in 2001.  The original platform design was for a 150m cruise boat.

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You're right - the Stena ferry was a bit of an outlier and I forgot all about them

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40 minutes ago, Zonker said:

You're right - the Stena ferry was a bit of an outlier and I forgot all about them

The Stena boats caused major issues in the industry.  They patented a whole lot of details Incat and Austal had already been using ie triangular window trusses and even some buoyancy distribution ratios that lead to Austal having to be really careful with the design of the forward half of their "semi-swath" hull form.

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On 4/7/2019 at 10:43 PM, Greenflash said:

A good question, thank you. 

There's so much crap out there it has become not a question of IF but unfortunately WHEN. Fortunately impacts are usually against small UFOS like logs. To protect against that the bows, boards and rudders have reinforced leading edges. The bow has solid carbon section and a decent amount of laminate. I believe this should save you from haul outs and repairs for small impacts. 

If you hit something at 20 knots though, that is a different story. Not a fun topic but worth planning for.

Boards: Any engineer will tell you it is very hard to engineer for grounding loads, so they simply bomb-proof the Daggerboard cases. There is a solid carbon and UD detail that is - "rather robust!" 

The goal is to have the boards shear off rather than any damage to the bearing housing, which could be catastrophic. 

 "Any engineer will also tell you" that the engineering for grounding loads and engineering so the boards sheer off are pretty similar.  Both have the same input (speed at which the boat hits an immovable object and the depth below the hull where the impact occurs) and result in the laminate required to break (or not)  at this speed.  If you can't calculate one, you certainly can't calculate the other.

Plenty of dagger boards break sideways, can't recall any sheering fore and aft.    And certainly not at a predetermined speed.   

How fast will the boat will be going when hitting a solid object causes the boards to sheer?   Any test results to back this up?

"Damage to the bearing housing may be catastrophic", but it is small beer compared to the damage to anyone not tied in or lying down with their feet forward when the boat decelerates from 20+ knots to near zero when (not if) the dagger board hits a whale, container or decent log.    Reinforcing the leading and trailling edges of the boards and a bulletproof case makes the stopping more abrupt.  

 

 

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Something I've asked a few structural engineers is if we should actually put a solid metal (Ti?) wedge at the back of the board, just attached/glued to the back of the case/housing. This would help to really cut the board if it starts to move aft into the bearing structure. 

I've had mixed responses. Some like the idea because they know their hull structure won't be compromised in case the - as you say - quite rigid fwd-aft shape of the daggerboard doesn't break and starts cutting into the boat. 

All I know is that there is no way one of our daggerboards will stay 100% in tact when a 20 ton boat stops dead after sailing at 20 knots. You probably could make it strong enough, but the structure is highly engineered to be light for a reason. Personally I really like the idea of a board being the weak point. Something is going to break at that speed and the boards absorbing, crushing and/or breaking first, absorbing a lot of the energy before it goes into the hull sounds like a good idea.

The boat can keep sailing on the other board, or without boards and it is a replaceable component.  

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There was a Gunboat 66 that sailed at full speed into a reef with boards down. It was pretty cool to see how the boards failed. The trunks were (more or less) fine. You could see how the foam on the trailing edge of the boards compressed before the spar failed. Apparent it was a bitch getting the board out of the trunk after it wedged itself in (as you'd expect) but they got it done. We NDT'd the trunk a couple of years later and it was all fine. Full credit to MM for designing it so well!

 

(For the record, I wasn't aboard when it happened!) 

 

 

IMG_6707.JPG

IMG_6707.JPG

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24 hours ago Condor was reported at 19/-50.  If I am correct, she’s travelled 1,200KM in about five days and still has 1,000KM to go. Unless she speeds up,  she still has three more days to go. 

240KM does not sound like a screaming fast passage.  Wonder if they are backing off the accelerator b/c she’s new or winds are v/light. 

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1 hour ago, soma said:

The trunks were (more or less) fine. You could see how the foam on the trailing edge of the boards compressed before the spar failed.

Holy smokes that is actually pretty awesome. I've never seen those images before and really glad it failed like I've always imagined it will. I think with the metal knife/edge you wouldn't have the wedge issue, so I'm sticking to my crazy idea for now :D

edit: typo

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If the board shears off, the boat isn't going to slow down much - too much energy to dissipate.

If the board stays intact, the boat slows down very fast. Like a keel boat hitting a reef. Much bigger loads into the trunk.

I'd rather shear the boards (having lost two myself!)

 

 

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HA!   I know it can't be so but my first thought when looking at the crushed area is Bondo pink. 

The pic itself is very comforting confirmation of what many people claim will happen when a well designed board system hits something hard, ie. to preserve the integrity of the hull.

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I'm not aware of any other filler that comes in that color and had exactly the same thought....the epoxy fillers are generally white, the vinylester green...

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System 3 "Quickfair" is a lighter shade of that same colour (do they all buy their balloons from the same guy?). 

Lot of bog there was my first thought  - but I imagine the junction where the board exits needs a lot of glass and you've got to fair it in.

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You'd be horrified to see how much fairing is on the SA boats. It got worse over time, too, as the tooling got older. 

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I helped write the specification for an aluminum fast 45 knot power yacht we designed. It read something like

"hull surface shall be fair such that the largest gap under a 1m long ruler placed anywhere on the hull shall be no more than the thickness of a #1 paperclip"

"this is to be the bare hull BEFORE any hull fairing compound is applied"

That's about 0.8mm over a 1m length. They are very good aluminum builders. We agreed on this standard before writing it in; don't want to put in something that is impossible/impractical.

I've found that about 1mm over 1m length is achievable by very good builders.

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at first I didn't see the "#1" part so I was like: easy!

Paperclip-1_1024x1024.jpg?v=1361663570

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The failure strategy on the original GB66 boards is no longer viable.  Those original boards were low aspect ratio with low bending moment requirements.  It’s hard to believe now but they contained end-grain mahogany and foam for core.  A great deal more lift is required from modern boards.  There is no longer structural space for internal board materials that can compress upon impact.  The sharp aft edge of the daggerboard case to encourage trailing edge buckling is getting on the right track.  That solution; however, ignores the fact that the high-load daggerboards are crazy expensive, and take quite a bit of time to build.  Nobody wants to tell an owner that they just lost a season because of a grounding event.  I favor a solution with a self-aligning lower bearing insert that is sacrificial.  The trailing edge detail of this insert must be carefully designed and engineered.  Energy must be gradually dissipated over a distance with pieces that “eject” as a board drags through the insert.  The idea is that the board and case survive a grounding event, but the insert does not.  Spare inserts can then be installed without much drama.          

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Wood shear webs and foam cores are used on some very advanced foils. 

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On 4/11/2019 at 12:17 PM, Student_Driver said:

24 hours ago Condor was reported at 19/-50.  If I am correct, she’s travelled 1,200KM in about five days and still has 1,000KM to go. Unless she speeds up,  she still has three more days to go. 

240KM does not sound like a screaming fast passage.  Wonder if they are backing off the accelerator b/c she’s new or winds are v/light. 

Getting there. She should arrive (somewhere) today. 

2700nm in +/-12 days. 9 knot average. 

IMG_6749.PNG

IMG_6750.PNG

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On 4/11/2019 at 8:22 PM, Greenflash said:

All I know is that there is no way one of our daggerboards will stay 100% in tact when a 20 ton boat stops dead after sailing at 20 knots. You probably could make it strong enough, but the structure is highly engineered to be light for a reason. Personally I really like the idea of a board being the weak point. Something is going to break at that speed and the boards absorbing, crushing and/or breaking first, absorbing a lot of the energy before it goes into the hull sounds like a good idea.

The boat can keep sailing on the other board, or without boards and it is a replaceable component.  

Maybe you are focussing on the wrong thing.  "WHEN, not IF a 20 ton boat hits something and stops dead after sailing at 20 knots" it is going to seriously damage anyone not strapped in.     Stand in the doorway of Condor and run as fast as you can into the steering console.   Then triple it.    And after "the board sheers off without catastrophic damage to the bearing",  what happens to the rudder?  How well does the boat sail with one rudder, and is this a "replaceable component" as well?  

Any Old User Name,

Thanks for the injection of reality, although I quite like the idea of end grain mahogany for a shear web/load spreader.  Your solution is better than the wishful thinking above, but the solution is far easier, cheaper and lighter.  

Make the boards (and rudders) kick up.  

Your post impressed me  enough to look at some of your others.  eg "My question is if someone gets hurt, then what is the designer's share of the responsibility?  Is it OK to design a boat with little regard to the safety of those onboard?  If that is what the client request, then is the design office absolved of responsibility?  Aside from ethical obligations, it seems to me that market forces would motivate a design office to defend safety.  It cannot be good for business if someone gets seriously injured on one of your designs."  

 

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Posted (edited)

Oh, and Condor is in Sint Maarten, in the lagoon, as expected.

Edited by Whiskey.T
typo
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11 hours ago, soma said:

Getting there. She should arrive (somewhere) today. 

2700nm in +/-12 days. 9 knot average. 

Damn, that ain't bad for a boat still most probably figuring it all out and sailing conservatively. Most probably not in straight line either. Good stuff. Looking forward to seeing that boat in person.

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It seems pretty obvious that if you're wanting to be far from help and yet sail fast it's unsafe to be choosing between either a sudden stop or catastrophic failure.  Kick up foils just make sense.  Rudders are important, and so is keeping the water out.  And a dead stop from speed would be really ugly.  What does your spinal column do if you're in your bunk and slam head first into a bulkhead at 20knts?

Anyway, gunboats aren't for that sort of sailing.  They're for showing off near the islands and then having paid crew do the long miles, then paying others to do the endless maintenance.  The whole concept offers almost no lessons for people who don't have that ethos.

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Marv, I'd guess that the majority of multihulls plying the oceans have daggerboards and the vast majority of monohulls have fixed keels and fixed rudders. Boats are a compromise. If you want kick-up foils, you compromise performance and add complexity and weight.

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38 minutes ago, bigmarv said:

It seems pretty obvious that if you're wanting to be far from help and yet sail fast it's unsafe to be choosing between either a sudden stop or catastrophic failure.  Kick up foils just make sense.  Rudders are important, and so is keeping the water out.  And a dead stop from speed would be really ugly.  What does your spinal column do if you're in your bunk and slam head first into a bulkhead at 20knts?

Anyway, gunboats aren't for that sort of sailing.  They're for showing off near the islands and then having paid crew do the long miles, then paying others to do the endless maintenance.  The whole concept offers almost no lessons for people who don't have that ethos.

OUCH, man, that's a little too harsh.... as Greenflash noted, they (being GB) sail a lot of miles, many with paid crew, but part of that equation is that ocean crossings at times are boring and at times just no fun. If you have limited time and still want to enjoy your boat, it makes sense to have someone move the boat or stick it on a container ship. When you hit something in the water you just don't go from 20 knots to zero, it does not happen that way, something breaks, shears off, something, but 99.9% of the time the people in the boat aren't slammed into the helm station causing terminal injuries.

Center boards really cannot take the loads imparted. I believe that the GB68 made in France is gonna be one fine boat that is wicked strong. The French have great builders and love the sport of sailing.

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Saw Condor sitting at anchor as we landed in St Maarten today. She looked beautiful. 

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1 hour ago, soma said:

Saw Condor sitting at anchor as we landed in St Maarten today. She looked beautiful. 

Pictures or it never happened :D

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