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Blade's strengths and weakness? #120495
10/19/07 10:42 PM
10/19/07 10:42 PM
Joined: Apr 2004
Posts: 713
WA, ID, MT
davefarmer Offline OP
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Seth's decided he's not ready to part with his Taipan yet. So now I'm looking at Blades as well. Anyone got observations on this boat? I got pretty universal praise for the Taipan, are you all as happy with the Blade? These boats are built really light, aren't you seeing them break some? Thanks!

dave

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Re: Blade's strengths and weakness? [Re: davefarmer] #120496
10/19/07 10:51 PM
10/19/07 10:51 PM
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St Petersburg FL
Robi Offline
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Dave:
All boats have their good stuff and their bad stuff. I have had issues with my boat in the past. Nothing that quick fixes cannot address the problems. Most of the problems were user error.

I did change a good majority of blocks lines and some minor things to make the boat easier to race ONE UP.

What would I change on the blade? Well if I were the dealer I would ask the buyer if they plan on racing mostly two or one up. I do believe the new blades are more inclined to two up racing. But this is no perfect world or perfect market so we must work with what we can get and only improve or make things better for each individual.

Re: Blade's strengths and weakness? [Re: Robi] #120497
10/20/07 01:05 AM
10/20/07 01:05 AM
Joined: Jan 2006
Posts: 13
Dubai, UAE
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Having had mine for a year and just recently helping build two new blades. On mine I've replaced ropes, cleats etc and moved things to where I want them. I think the new blades are pretty much spot on regarding fittings. Matts done a great job evolving his product & out of the box, there's nothing I would change (except tiller extension)!


Dave H VWM Blade F16 UAE719 Dubai
Re: Blade's strengths and weakness? [Re: davefarmer] #120498
10/20/07 05:22 AM
10/20/07 05:22 AM
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North-West Europe
Wouter Offline
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Having sailed all versions of the Blade I agree that the evolution is there. On the very last day of the Zandvoort event (second day of distance racing) I crewed for Geert on his Alter Cup boat. I can only say :"WOW, what a upwind monster". We had heard these comments form the US Alter Cup sailors and I can only concur. That sail design is just right.

I'm very happy with Taipan but I do think the Blade is overall better. The strong points of the Taipan are its 1-up performance in very light winds. Blade's are nicer in all other conditions in my opinion. The only real caveat is that big wind under spinnaker the Blade stays flat and calm for all the way up to the threshold and then falls off it. The Taipan is certainly less dive-happy, it is in fact more so but because the bows start nodding a little before meeting the actual threshold you get ample advance warning, on the boat you can power it up all the way to inches of the threshold and feel like you have still acres left. That is what get most newbies and a few experiences sailors as well. But once get the know the craft better you'll know where the push and were to hold back a little. In my opinion the Stealth has its strong point right there with the T-foils. And so we have covered all 3 strong points of each boat. The Viper and Aussie Blade are still to young to be judged on this but they are said to be a little bit more forgiving downwind in a blow as well. It certainly looked that way.

Also there is another thing that most F16 sailors do well to learn. It simply pays so much to anticipate the wind and gusts on the downwind legs. If you are a fraction to late then yes the bows goes (but still recovers all the time) be on time and you drive it deep and accellerate fast with each gust. Timing is absolutely everything here. If a guyy is walking away from you under spinnaker (like Tim I expect) then it is this that he is doing right. It will feel like you are bearing off and heading up again BEFORE the gust is there. Look for, train yourself on it and experience the results.

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Blade's strengths and weakness? [Re: davefarmer] #120499
10/20/07 05:55 AM
10/20/07 05:55 AM

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Hi Dave,

I would not call the "Formula Catamarans Australia" Blade (the only one I have experience with) lightly built. It is every bit as strong as the Taipan, with it's standard Kevlar outer skin and Kevlar reinforcing of bulkheads and frames it seems bullet proof <img src="http://www.catsailor.com/forums/images/graemlins/tongue.gif" alt="" />. Or at least Hobie 16 proof so far, I have hade one bounce of leaving a dent but no cracking of the skin. <img src="http://www.catsailor.com/forums/images/graemlins/shocked.gif" alt="" />

Re: Blade's strengths and weakness? [Re: Wouter] #120500
10/20/07 07:16 AM
10/20/07 07:16 AM

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Wouter, what makes the Aussie Blade different from VWM wrt downwind behavior? Are there any differences in hull shape?

Re: Blade's strengths and weakness? [Re: ] #120501
10/20/07 01:17 PM
10/20/07 01:17 PM
Joined: Apr 2004
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WA, ID, MT
davefarmer Offline OP
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Wow! Thanks you guys! This feedback is wonderful, and it seems that these are all well sorted, solid boats. I look forward to joining the club!

Dave

Re: Blade's strengths and weakness? [Re: davefarmer] #120502
10/20/07 07:03 PM
10/20/07 07:03 PM
Joined: Dec 2005
Posts: 443
Edmonton, Alberta, Canada
bobcat Offline
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Speaking as a sailor who moved from a 70's Nacra to a 00's Blade I was surprised at how 'tender' the hulls are. I think I already had a dent before the boat had hit the water. After a couple of capsizes, the insides of the hulls are starting to resemble golf balls, with elbow and knee dents.
My boat isn't Kevlar. Kevlar may be something to look for.

Re: Blade's strengths and weakness? [Re: bobcat] #120503
10/20/07 07:15 PM
10/20/07 07:15 PM
Joined: Aug 2005
Posts: 2,921
Michigan
PTP Offline
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I think the dents are a product of the lightweight construction. The hulls aren't glass core, it is foam core so it doesn't take much to dent the outer skin in. I certainly have more than a few. Not sure kevlar would makes much of a difference.
The HT that I had before had the same issue and the construction is largely the same.

Re: Blade's strengths and weakness? [Re: davefarmer] #120504
10/20/07 09:55 PM
10/20/07 09:55 PM
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Eastern NC, USA
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tshan Offline
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Quote
are you all as happy with the Blade? These boats are built really light, aren't you seeing them break some? Thanks!


My thoughts on buying a used US based VWM Blade:
1. Make sure the hulls are kevlar (almost all are). Look for dimpling, as described in earlier posts.
2. Check whether the daggerboards leak (my first low aspect boards leaked)
3. Inspect the rudders closely (the earlier types cracked at the rudder head)

That's about it. Most of these items have already been replaced on all early VWM Blades, but if you are looking for things to check - then that is it.

Later models of the VWM have already have these evolutions in place. It is an evolution and things do get better in each cycle. This is not a trend for VWM boats, but for all boats. Certain hull numbers have always been coveted because they are "stiffer" or "better built" - N5.2 2300 series boats are "the fastest" still today.

AHPC has had many more boats built from their moulds and have had a chance to perfect their product. US built VWM Blades have had many fewer boats built, but have been improving them with each cycle. The latest boats have been VERY good, IMO. The Blades are just as well built, just make sure they have been taken care of and kept up to date.

You will find lemons in every line of boat/car/golf club/etc. You just need to know what to look for.

Last edited by tshan; 10/20/07 09:59 PM.

Tom
Re: Blade's strengths and weakness? [Re: tshan] #120505
10/20/07 11:47 PM
10/20/07 11:47 PM
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St Petersburg FL
Robi Offline
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Tom, I remember you and Terry ran into dagger board and or rudder problems. I have one of the same dagger boards and rudders and have never had to deal with delam problems. WIERD!

Also another thing that some other people were having problems with was the jib compression struts, ive raced my boat hard uni and sloop and never had issues. My boat does have the small dimples here and there, but those never slowed me down.

LOL

Re: Blade's strengths and weakness? [Re: PTP] #120506
10/21/07 04:57 AM
10/21/07 04:57 AM

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Hi all,

as suggested I would agree that Kevlar makes no difference when it comes to dents, the amount of denting that occurs in a Glass or Kevlar outer skin is a result of the core stiffness, as was said, solid glass boats had little trouble with this but they are to heavy and flexible for a F16 hull.

So the amount of denting is reliant on the density of the foam core on boats like Taipans and Blades and then it is still a balancing act between weight and dent resistance,along with thickness for overall stiffness. I have certainly seen some Mosquito's in OZ that dent to easily. Can not comment on those in the US, it may be worth asking the manafacturer if he has altered foam core density at all, as that is what they did with the Mossies in OZ.

Re: Blade's strengths and weakness? [Re: ] #120507
10/21/07 09:05 AM
10/21/07 09:05 AM
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fin. Offline
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I can't think of anything I would call a weakness. The cosmetic dimpling I have results from hitting things or dropping it off the trailer <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" />.

Fortunately, I havent't hit any channel markers (with the hull) yet <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />.

Re: Blade's strengths and weakness? [Re: fin.] #120508
10/21/07 09:07 AM
10/21/07 09:07 AM
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St Petersburg FL
Robi Offline
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Quote
I can't think of anything I would call a weakness. The cosmetic dimpling I have results from hitting things or dropping it off the trailer <img src="http://www.catsailor.com/forums/images/graemlins/blush.gif" alt="" />.

Fortunately, I havent't hit any channel markers (with the hull) yet <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />.
Or those pesky anchor lines that always get in the way. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Re: Blade's strengths and weakness? [Re: Robi] #120509
10/21/07 09:17 AM
10/21/07 09:17 AM
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fin. Offline
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I don't like the mast rotation. It's fine if you adjust between races, but I'm unable to tweak it while racing. That's a personal mod. though.

Re: Blade's strengths and weakness? [Re: Robi] #120510
10/21/07 09:51 AM
10/21/07 09:51 AM
Joined: Mar 2006
Posts: 1,246
Orlando, FL
tback Offline
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[/quote]Or those pesky anchor lines that always get in the way. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> [/quote]

HAHAHAHAH

Yea Robi, that was an incredible sight. Sorta' like stubbing your toe on the (elevated) crack in the sidewalk and finding your face on the cement!

But more damage to the foils that dimpling your hulls ... unless you count the dimple on your forehead from smacking the water.

HAHAHAHA


USA 777
Re: Blade's strengths and weakness? [Re: ] #120511
10/21/07 10:29 AM
10/21/07 10:29 AM
Joined: Jul 2001
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Western Australia
Stewart Offline
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the manufacturers can make the area around the "dimple" area harder.. by increasing the foam density in that area and adding a second layer of skin.. Reducing density in other areas as well as decreasing glass/kevlar/carbon in non dimple areas..
Just things that are modified as builders get more experienced with their product..

<img src="http://www.catsailor.com/forums/images/graemlins/crazy.gif" alt="" />

Re: Blade's strengths and weakness? [Re: tback] #120512
10/21/07 10:34 AM
10/21/07 10:34 AM
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fin. Offline
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Quote
[/quote]Or those pesky anchor lines that always get in the way. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />


HAHAHAHAH

Yea Robi, that was an incredible sight. Sorta' like stubbing your toe on the (elevated) crack in the sidewalk and finding your face on the cement!

But more damage to the foils that dimpling your hulls ... unless you count the dimple on your forehead from smacking the water.

HAHAHAHA [/quote]

I take it your team lost. . . again <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />.

Re: Blade's strengths and weakness? [Re: fin.] #120513
10/21/07 10:51 AM
10/21/07 10:51 AM
Joined: Mar 2006
Posts: 1,246
Orlando, FL
tback Offline
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No actually played pretty good. Held the #2 ranked offense in the country to 23 pts ... while we scored 44. Yipppee.

Much better than the drubbing we took at So.FL last week.


USA 777
Re: Blade's strengths and weakness? [Re: Robi] #120514
10/21/07 11:14 AM
10/21/07 11:14 AM
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Eastern NC, USA
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tshan Offline
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Quote
Tom, I remember you and Terry ran into dagger board and or rudder problems. I have one of the same dagger boards and rudders and have never had to deal with delam problems. WIERD!


Exactly right, Robi. I did not intend to imply that all boards and rudders were bad - but there were a limited few problems. It'd be a good thing to check prior to purchasing a 2004/2005/2006 Blade, imo.


Tom
Re: Blade's strengths and weakness? [Re: tshan] #120515
10/21/07 11:56 AM
10/21/07 11:56 AM
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Orlando, FL
tback Offline
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I had a delamination problem with one rudder (an original carbon fibre rudder--not being produced any longer), VectorWorks replaced both rudders without question.


USA 777
Re: Blade's strengths and weakness? [Re: ] #120516
10/22/07 08:42 AM
10/22/07 08:42 AM
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_flatlander_ Offline
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Hi all,

as suggested I would agree that Kevlar makes no difference when it comes to dents, the amount of denting that occurs in a Glass or Kevlar outer skin is a result of the core stiffness, as was said, solid glass boats had little trouble with this but they are to heavy and flexible for a F16 hull.

So the amount of denting is reliant on the density of the foam core on boats like Taipans and Blades and then it is still a balancing act between weight and dent resistance,along with thickness for overall stiffness. I have certainly seen some Mosquito's in OZ that dent to easily. Can not comment on those in the US, it may be worth asking the manafacturer if he has altered foam core density at all, as that is what they did with the Mossies in OZ.

and from Bobcat
Quote
My boat isn't Kevlar. Kevlar may be something to look for.

and from PTP
Quote
Not sure kevlar would makes much of a difference.

and from Tom (tshan)
Quote
1. Make sure the hulls are kevlar (almost all are).

So is there a consensus here? Are you saying kevlar reduces, but does not eliminate dimpling?

Are there other attributes or drawbacks of a kevlar outer skin?
For instance, added resistance to puncture wounds?
More difficult to repair?

Thanks


John H16, H14
Re: Blade's strengths and weakness? [Re: _flatlander_] #120517
10/22/07 08:45 AM
10/22/07 08:45 AM
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Edmonton, Alberta, Canada
bobcat Offline
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I am probably in the same boat as you actually. I know little about Kevlar but what has been written here. I think that it is more puncture resistant and I guess I extended that to more dent resistant.

Re: Blade's strengths and weakness? [Re: _flatlander_] #120518
10/22/07 10:23 AM
10/22/07 10:23 AM
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I think Kevlars greatest virtue is puncture resistance.

Re: Blade's strengths and weakness? [Re: fin.] #120519
10/22/07 03:16 PM
10/22/07 03:16 PM
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St Petersburg FL
Robi Offline
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Bulletproof baby!

Re: Blade's strengths and weakness? [Re: fin.] #120520
10/22/07 03:42 PM
10/22/07 03:42 PM
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Central California
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I have an AHPC Kevlar Taipan that seems to be very strong and I have not seen any dimpling, leaking, daggerboard well issues, delamination, etc. I have no idea about the Blade.


Eric Poulsen
A-class USA 203
Ultimate 20
Central California
Re: Blade's strengths and weakness? [Re: _flatlander_] #120521
10/22/07 04:38 PM
10/22/07 04:38 PM
Joined: Jun 2005
Posts: 61
Northwest-Germany Hamburg
Holger Offline
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The outer layer of a sandwich composite has to withstand tensile loads and the inner layer compression loads in case of an impact.
When we compare the different laminate materials:
Tensile strength [MPa] E-glass 2400, Kevlar 3000, Carbon 4000,
we see that carbon is the strongest material, but in case of an accident Kevlar has it's large advantage over the other materials.
Strain at break point E-Glass 4.5%, Kevlar 2%, Carbon 1.2%.
The 1.2% figure for carbon fibre indicates that though very strong it is also very brittle and will break shortly after the load stress passes yield point.

So the advantage of Kevlar as outer layer is, that it is lighter than glass, stronger in tensile strenght and not brittle.

In case of repair Kevlar will fuzz at the surface if you want to sand it, and it is hard to cut. It must be covered with glass or gel coat.

Here the source for the above mentioned with more technical background:
http://oneoceankayaks.com/Sandcore.htm
http://www.auf.asn.au/scratchbuilder/composites.html


-------------
Dynautic Blade F16-GER 001
Re: Blade's strengths and weakness? [Re: Holger] #120522
10/23/07 03:13 AM
10/23/07 03:13 AM
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Finland
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There are only two small drawbacks with Kevlar. It's sensitive to light (UV) and absorbs a lot of humidity???
Two good reasons why not to use it in boatbuilding.

Re: Blade's strengths and weakness? [Re: Gato] #120523
10/23/07 03:19 AM
10/23/07 03:19 AM
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Those are not good reasons to discard Kevlar as Carbon is at least as sensitive to UV when untreated and glass is at least as hydrophile as Kevlar can ever be. Both other materials are used extensively so why not Kevlar.

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Blade's strengths and weakness? [Re: Wouter] #120524
10/23/07 03:47 AM
10/23/07 03:47 AM
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Finland
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Still the reason why the aircraft industry has almost abandoned Kevlar is the problem with waterabsorbing...

Re: Blade's strengths and weakness? [Re: Wouter] #120525
10/23/07 09:23 AM
10/23/07 09:23 AM
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Farrier will not allow Kevlar on the outer skin, not sure why, can anyone enlighten me, he also is quite open that you can use carbon on the outer skin but to get dramatic weight savings, the skins become so thin that they cannot withstand the impact loadings of crashing into things. He advocates glass and a good layer of it as it is very resillient to dings etc ?, easy to repair, cheap to manufacture and does the job, any weight savings can be saved elsewhere. <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />

Re: Blade's strengths and weakness? [Re: waynemarlow] #120526
10/23/07 11:25 AM
10/23/07 11:25 AM
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Quote
Farrier will not allow Kevlar on the outer skin, not sure why, can anyone enlighten me,
Back to what Holger said
Quote
In case of repair Kevlar will fuzz at the surface if you want to sand it, and it is hard to cut. It must be covered with glass or gel coat.
Concured by extensive search of "kevlar" on this forum (after I asked) seems the common layering is gelcoat, glass, then kevlar.

The common theme for kevlar use is not structural strength, but improved dent resistance


John H16, H14
Re: Blade's strengths and weakness? [Re: Gato] #120527
10/23/07 11:30 AM
10/23/07 11:30 AM
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Northwest-Germany Hamburg
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How does the water come to the Kevlar strands as long as it is bedded in the epoxy matrix? Epoxy does not absorb water, like polyester or vinylester. So when the Kevlar is stored dry prior the laminating process, everything would be ok? And most builders use a gelcoat or painted surface which inhibits UV.


-------------
Dynautic Blade F16-GER 001
Re: Blade's strengths and weakness? [Re: Wouter] #120528
10/23/07 11:36 AM
10/23/07 11:36 AM
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Western Australia
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its the epoxy that is UV sensitive and heat sensitive... Maybe heat isn't an issue where you are.. It is here, so those in the know just paint the hulls...

Re: Blade's strengths and weakness? [Re: _flatlander_] #120529
10/23/07 05:55 PM
10/23/07 05:55 PM
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dent resistance comes predominantly from the core density, particularly with the very light skins; carbon, kevlar or glass; used on our size boats. The thickness of skins on our size boats range from 0.25-0.5mm. That's why hard points are de-cored or have the core replaced by a harder core.

Re: Blade's strengths and weakness? [Re: ncik] #120530
10/23/07 08:11 PM
10/23/07 08:11 PM
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Thailand
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The Kevlar is stiffer and doesn’t dent (just be sure to leave the car/house keys at home and not in your back pocket)... <img src="http://www.catsailor.com/forums/images/graemlins/cool.gif" alt="" />


"House prices have risen by nearly 25 percent over the past two years. Although speculative activity has increased in some areas, at a national level these price increases largely reflect strong economic fundamentals." – Ben Bernanke – 2005
Re: Blade's strengths and weakness? [Re: Buccaneer] #120531
10/23/07 08:41 PM
10/23/07 08:41 PM
Joined: Sep 2003
Posts: 264
Long Island, NY
gregP19 Offline
enthusiast
gregP19  Offline
enthusiast

Joined: Sep 2003
Posts: 264
Long Island, NY
I'm changing from the "hook" system to the "keyhole" system for my harness. To me that is a good way to be proactive in the interest of minimizing holes in the hulls of my fragile Blade.


G Gove Blade #728 Long Island, New Yawk
Re: Blade's strengths and weakness? [Re: davefarmer] #120532
10/24/07 03:19 PM
10/24/07 03:19 PM
Joined: Jun 2005
Posts: 61
Northwest-Germany Hamburg
Holger Offline
journeyman
Holger  Offline
journeyman

Joined: Jun 2005
Posts: 61
Northwest-Germany Hamburg
I found that the round 80x2mm alu beams are not so stiff as expected. I think these are the recommended ones which most homebuilders use. In choppy waves i can see and feel some vibration in the platform. Compared from memory to my former Nacra 500 it is noticeable more.
Would a replacement with 80x3mm carbon tubes for example bring effectively more stiffness?
How far does a little more flexible platform suffer in speed compared to a optimized platform with more rigid beams? Probably working on my sailing skills has more effect than new beams, but it is always nice to have optimal material for the beloved sport.


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Dynautic Blade F16-GER 001
Re: Blade's strengths and weakness? [Re: Holger] #120533
10/25/07 04:28 AM
10/25/07 04:28 AM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline
Carpal Tunnel
Wouter  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 9,582
North-West Europe

80x2 beams are in the homebuilding plans because these are universally availbable the world over while having a good ration between weight and stiffness.

Not all stiffness comes from the beams, the stiffness of the beams landings and torsional stiffness of the hulls between the beams is important as well. Basically, we need to find out first what the case of your problem is and adress that.

Going for 80x3 mm beams will give you 50% more beam stiffness but this will not translate directly into 50% stiffness increase of the whole platform because of the other factors named above.

Weight increase (for 2 beams) will be about 4 kg.

It is worth a try, but I don't expect more then 25% stifness increase.

How much does the boat flex now ?

Measuring this involved laying the platform up on its sterns (without mast etc) and seeing how far one bow needs to be lifted before the other bow is lifted clear of its support as well.

By the way the nacra 500 (and nacra 5.0) used the beams of the larger boats like the Nacra 6.0 and F18's and that makes them very stiff for the Nacra 500. Of course this comes at a cost, in the case of the Nacra 500 this cost is roughly 50 kg additional boat weight and 20% slower performance.

Stiffness of a platform is important but certainly not all important. More stiffness is mostly better in the way of feel in very choppy conditions. In the way of all-out speed I'm not sure how important is really is.

Wouter

Last edited by Wouter; 10/25/07 04:31 AM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Blade's strengths and weakness? [Re: Wouter] #120534
10/25/07 03:11 PM
10/25/07 03:11 PM
Joined: Jun 2005
Posts: 61
Northwest-Germany Hamburg
Holger Offline
journeyman
Holger  Offline
journeyman

Joined: Jun 2005
Posts: 61
Northwest-Germany Hamburg
Quote

How much does the boat flex now ?
Measuring this involved laying the platform up on its sterns (without mast etc) and seeing how far one bow needs to be lifted before the other bow is lifted clear of its support as well.
Wouter


For a exact measurement in this manner I'll wait till the season is over, and I have to take the mast down. Probably beginning of the november. So far I enjoy the last sailing days with cold feet


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Dynautic Blade F16-GER 001
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