So the variations of Streaker development
Printed From: Yachts and Yachting Online
Category: Dinghy classes
Forum Name: Dinghy development
Forum Discription: The latest moves in the dinghy market
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=12988
Printed Date: 03 Jul 25 at 11:38am
Software Version: Web Wiz Forums 9.665y - http://www.webwizforums.com
Topic: So the variations of Streaker development
Posted By: iGRF
Subject: So the variations of Streaker development
Date Posted: 07 Feb 18 at 9:42pm
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Thought it better to start a separate thread, it could be interesting to talk about the different brands in the development of the Streaker, rather than it being buried in the Nat18 thread, story so far being a particularly quick in iffy conditions Streaker from Boatyards at Beer, it's number 1958 so I guess fairly recent, a nice little boat giving us in our Solutions a hard time which really it shouldn't.
So, somebody said something about the positioning of a buoyancy tank, can't see why that should make any difference but it certainly appears to sit higher in the water then the other Streakers of which there are a few at the Redoubt. Streakers have been sailed here since the dawn of time. I know there are tolerances and different layouts, some give you more legroom than others, that much I gleaned from a conversation at last years dinghy show talking to somebody about the Butler Boats model v another from a different builder. So that's about the gist of it, what more does the hive mind know? ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Replies:
Posted By: 423zero
Date Posted: 07 Feb 18 at 10:04pm
| Picture your Minisprint, when you move across boat back of boat sinks, increase buoyancy and it won't sink, probably sit higher too. |
Posted By: craiggo
Date Posted: 07 Feb 18 at 11:45pm
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I think a physics lesson is needed!
Bouyancy tanks/bags have absolutely no effect on how a boat sits on the water unless you allow water to come over the decks. A tank or bag simply stops water filling that volume of the boat. Changes in buoyancy tank position are largely ergonomic, or to reduce amount of water scooped up in a capsize. The only thing that will change the waterline is immersed shape of the hull and weight. Due to boats like the streaker originally being designed for homebuild in ply the tolerances are massive. The same can be seen in Solos where different designs are visibly different hull shapes. As has been said on the other thread I imagine they have gone for an extreme hull shape and it's down to weight, whereas the old ply boats knocking about may have taken on a few kgs over the years. ------------- OK 2129 RS200 411 |
Posted By: jeffers
Date Posted: 08 Feb 18 at 6:52am
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Same can be said of many OD home build classes including those already mentioned the Fireball and Phantom have both had hulls 'optimised' within the tolerances to make the best hull shape (according to the person who did the optimisation). The Solos have several hull shapes, some of which are reputed to be better inland, some better on the sea (the Winder Mk1 or 1a seems to be the favoured shape for people at Hunts). ------------- Paul ---------------------- D-Zero GBR 74 |
Posted By: Paramedic
Date Posted: 08 Feb 18 at 8:38am
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The Streaker falls into the same category as the Phantom in that modern materials mean that you can now build a boat thats stiff and down to weight. Previously they could probably have one or the other. Also the weight in the ends of the hull can be reduced without compromise. The boat will now float differently to a wooden one (And no comparison at all to a single skin GRP example!!), and pitch noticably less - and this does make a difference inland too. If they have also added volume to the bow section towards the extreme of the permitted tolerance that will change how the boat floats too. All of this is within the rules, though it does effectively divide the class. Similar changes, plus carbon rigs transformed the Phantom into a class that people actually wanted to sail. Its only going to make a Streaker faster too, and i'd suggest that sailed well by someone the right size in optimum conditions it will punch well above its perceived weight. The 5 point PY reduction for 2017 bears this out. Vs a Solution, they aren't too dissimilar and given that the three people I know who had a Solution were all disappointed with it and bought something else very quickly I'm not surprised that the Streaker performs to a similar level if well sailed. The Streaker is significantly lighter, but has significantly less sail area - maybe a more efficient combination?
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Posted By: Sam.Spoons
Date Posted: 08 Feb 18 at 9:23am
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Gut feeling, Streaker at 48kg, hard to build stiff and down to weight until modern materials came along so older boats all weight 53-55 kg. That's a difference of 10-12%. By the time you add a rig and a crew that % is at least halved. Should be easy to confirm though as they will all have been measured/weighed. ------------- Spice 346 "Flat Broke" Blaze 671 "supersonic soap dish" |
Posted By: seasailor
Date Posted: 08 Feb 18 at 10:55am
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Will it have been measured though? I'm sure I overheard a bloke down the pub saying it hadn't been.
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Posted By: iGRF
Date Posted: 08 Feb 18 at 11:09am
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Er... I realise an internal buoyancy tank makes no difference unless of course it's positioning affects the external shape and overall volume of the boat which clearly this model does. I also know changes have been made to the rear end of the Streaker, notably by Rooster, which looked quite tasty a few seasons back at the Dinghy Show.
One day they'll spot it's a lightweights boat it should have a carbon rig, they can't possibly use the 'it'll make older boats obsolete' excuse with all this other stuff going on, so I guess it's just the usually impecunious nature of the beast preventing complete modernisation. I was just wondering if anyone actually knew the difference of that tank positioning compared to say where it is on a Butler or Rooster boat. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: 2547
Date Posted: 08 Feb 18 at 11:13am
| I thought you said it sat higher due to bubbles in the foam ....snigger .... |
Posted By: L123456
Date Posted: 08 Feb 18 at 11:16am
Eureka ...
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Posted By: iGRF
Date Posted: 08 Feb 18 at 11:17am
That as well. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: Rupert
Date Posted: 08 Feb 18 at 11:18am
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I assume the foam sandwich construction is strong enough to hold shape without a bulkhead. If it was relying on it for shape the hull would distort over time. The hull shape will be governed by the shape of the mould, not internal structure, which will stiffen the whole boat, not change its shape.
Be lovely to hear from the builder whether they have had different thoughts on boat shape from others, or whether this is simply either a weight thing or imagination. A Carbon mast on such a light boat would make a lot of sense, given how far the whole thing has strayed from its 1975 cheap and easy homebuild concept anyway. ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: iGRF
Date Posted: 08 Feb 18 at 11:23am
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Next time I'm down there and the weather is clement, I'll try and get some pictures alongside other Streakers, there are a few different types down at the Redoubt, it will be interesting to find out, I'll also have a chat with Dave Butler, he's building me a Farr 3.7 at the moment I expect he has some thoughts on how Streakers get built. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: Rupert
Date Posted: 08 Feb 18 at 11:26am
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Get Mr Butler to report straight to the forum. We won't trust you not to put spin on things, or maybe simply get the wrong end of the stick. ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: L123456
Date Posted: 08 Feb 18 at 11:29am
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iGRF .... do some reading up on displacement ... Maybe eat a nice bubbly aero bar whilst you are at it rather than a solid bar of Dairy Milk .... |
Posted By: iGRF
Date Posted: 08 Feb 18 at 12:08pm
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Let me finally put this bubbles in the foam thing to rest and this Streaker is exactly an opportunity being built over ribs.
So if the boat is assembled with ply over ribs it is not going to float as high as a boat assembled with say Nomex foam over the ribs. However if the ply were assembled within a female mould somehow, then there would be no significant difference. But what essentially we need to know here is how the boats are assembled are they in a mould, within CAD produced ribs right out to the measurement, or over traditional male rib formers, each one will have a different effect on the flotation or what you lot call displacement. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: Ardea
Date Posted: 08 Feb 18 at 12:33pm
| The cost and maintenance aspects of carbon spars are probably the biggest barrier to adoption. A streaker sails nicely enough with the aluminium rig (which is pretty basic- constant section mast). I'd suspect the additional purchase cost and maintenance of carbon spars for a boat, which already sails nicely, is not going to generate new owners or be worth the finacial outlay. |
Posted By: davidyacht
Date Posted: 08 Feb 18 at 12:40pm
This is a wind up isn’t it ... given that the poster would know why a 75 ltr board is a sinker ... well maybe not for him ... ------------- Happily living in the past |
Posted By: Sam.Spoons
Date Posted: 08 Feb 18 at 1:06pm
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Must be David, if they are the same shape (and I know they vary a little) the only thing that will make it float higher is if it's lighter. T'is basic physics (as some bloke, lacking a towel, asserted a couple of thousand years ago)..... ------------- Spice 346 "Flat Broke" Blaze 671 "supersonic soap dish" |
Posted By: Gordon 1430
Date Posted: 08 Feb 18 at 1:25pm
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It could be the Helms lighter. ------------- Gordon Phantom 1430 |
Posted By: davidyacht
Date Posted: 08 Feb 18 at 1:31pm
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Differences in relative density of water at different ends of the lake? ------------- Happily living in the past |
Posted By: iGRF
Date Posted: 08 Feb 18 at 1:35pm
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Most of the helms in Streakers (at our place)are pretty light, I'd say this guy is around the 70-75kg mark and one of the Streaker helms is less than 60 (yet quite tall) and his boat I believe is ply, another Streaker is helmed by a guy still shy of 80 kgs and it's a Rooster model from about 4-5 years ago. They are all pretty OK helms and will have their moment at the front, but there's just a little more consistency with this Boatyard @ Beer model, but then it's also new and that can count for a lot, everything else down there is pretty tired. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: iGRF
Date Posted: 08 Feb 18 at 1:37pm
You might jest, but... It is in close proximity to the sea ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: Rupert
Date Posted: 08 Feb 18 at 3:09pm
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So, 2 boxes, identical external dimensions and weight. One made from low density material, 1/2 inch thick, the other from high density material 1/4 inch thick. Identical, especially in every other way. If I float them in my bath, they will displace identical amounts of water. How are identical boats different? ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: iGRF
Date Posted: 08 Feb 18 at 3:59pm
Your box scenario is correct, but it's not like that is it? Now if one box were made with a frame and the wood attached to it and the other box was made within a mould of what the box size should be... ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: ian.r.mcdonald
Date Posted: 08 Feb 18 at 4:00pm
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just dont think about arranging a boat swap for a couple of races. If the helm from the "fast" boat is still up there in a different boat you have a problem.
put someone competent in a new boat with their head full of all the " marketing speak" of fast shapes etc etc and they will be towards the front of many fleets |
Posted By: Rupert
Date Posted: 08 Feb 18 at 4:13pm
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Yes, I've seen plenty of identical boats, especially when it comes to how high they float.
And yes, if one box is built ply on frame, and the other laid up in a female mould, but they come out the same size and weight, they will float the same in the bath. So, what we are really looking at is hull volume and weight, neither of which are a direct result of any one construction method or material. ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: Sam.Spoons
Date Posted: 08 Feb 18 at 4:34pm
How about making a wooden Streaker, then taking a mould from it and building a second monocoque FRP Streaker (no frames) but built to the same weight? They would float to exactly the same marks but, probably, the FRP boat would be stiffer and probably faster for that reason. Changes in the hull shape may make it look as if it was floating higher (or lower) e.g. max rocker and vee would probably displace the same volume of water with it's ends a little higher than a flatter design (I think Dan H, you should be able to answer this?) and that would change the performance, the flatter boat would carry more wetted area and be a little slower in the light but would plane a little sooner all else being equal. ------------- Spice 346 "Flat Broke" Blaze 671 "supersonic soap dish" |
Posted By: salmon80
Date Posted: 08 Feb 18 at 11:37pm
Not quite true. A ply hull with 5mm ply and battens that flexes in the floor might sit lower than a stiff boat of the same shape and weight. |
Posted By: Rupert
Date Posted: 09 Feb 18 at 8:18am
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Unlikely that any of the boats being looked at are that badly built? I can see nose or stern heavy boats floating at a different angle in the water, which would make them look rather different, more so than a couple of kilos of weight. ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: iGRF
Date Posted: 09 Feb 18 at 10:50am
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I suppose the acid test is to find out which boats are winning at the Nationals. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: iGRF
Date Posted: 09 Feb 18 at 11:48am
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Well that wasn't difficult Butler Streakers seem to be killing it, but this new Beer design finished third, so it's up there, and it took the first race, I don't think we've got any Butler Streakers at the lake, Mine of information that Streaker Class site, I suppose I have to grudgingly admit that some classes do a reasonable job, if only they'd overcome their fear of carbon... ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: zeon
Date Posted: 10 Feb 18 at 4:27pm
| Don’t think they will go down the carbon mast route in the short to medium term, but I do know they were testing a carbon boom last year. No idea how far along they are along making it class legal. |
Posted By: ian.r.mcdonald
Date Posted: 10 Feb 18 at 4:54pm
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Nobody want to consider that a greater percentage of new boats are sailed either the semi pro sailmaker,chandlers etc alongside the keener and more committed? and that the main reason for being in the front half of the fleet is the " nut on the tiller"?
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Posted By: Rupert
Date Posted: 10 Feb 18 at 8:10pm
Hasn't it always been, in every class? ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: iGRF
Date Posted: 10 Feb 18 at 8:21pm
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Well if that were the case, there wouldn't be semi pro jocks from various builders and sailmakers, would there? ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: Rupert
Date Posted: 10 Feb 18 at 8:27pm
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I was thinking more of the "nut on the tiller" bit, but yes, in a multi builder one design with an open sail maker you'd expect representatives from quite a few companies. Can make it hard for reasonably talented amateurs to get into the top 10. ------------- Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686 |
Posted By: 423zero
Date Posted: 10 Feb 18 at 9:08pm
| Helps semi-pros to keep sharp and fund their sailing progress, how many olympians traveled this route ? |
Posted By: iGRF
Date Posted: 10 Feb 18 at 9:20pm
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I guess that's the attraction of SMODs where one builder dominates so therefore more likely to attract amateurs but then you have to put up with heavy and crap build coupled to bad design and next to no improvement. ------------- https://www.corekite.co.uk/snow-accessories-11-c.asp" rel="nofollow - Snow Equipment Deals https://www.corekite.co.uk" rel="nofollow - New Core Kite website |
Posted By: turnturtle
Date Posted: 11 Feb 18 at 6:48am
It Helps keep the class talent up too... I’m sure I’m not the only person who would be more impressed by a mate doing a top 10 in certain nationals vs winning a noddy class one. Correct use of sailor classifications could put category prizes into the overall mix and from what experience I’ve had, ‘rockstars’ and jockeys make a hell of a worthwhile contribution to any class over and above their entry free and copious cellar of low grade trophy wine. |
Posted By: E.J.
Date Posted: 11 Feb 18 at 8:51am
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Totally agree, the quality of the top guys drag the standard up as well as they are confident and competent enough to try new things. As a weekend warrior I benefit hugely from the influence of the semi pros and would choose a high profile class , it’s likely to the most active thanks to them. ------------- |