Announcements
New Discussions
Previous Thread
Next Thread
Print Thread
Rate Thread
Hop To
Page 2 of 2 1 2
Re: F16 and Curved Boards [Re: scooby_simon] #232962
05/30/11 10:18 AM
05/30/11 10:18 AM
Joined: Jun 2001
Posts: 1,021
Australia
macca Offline
old hand
macca  Offline
old hand

Joined: Jun 2001
Posts: 1,021
Australia
Ahh, Hans thinks he is agreeing with me but infact...

I believe that the curved boards will be easy to get an increase in performance with for even your average sailor.

On the a class you are constantly trying to reduce drag, downwind you dont have the option of doubling your sail area and as such you need to sail the boat very differently.

The F16 will be markedly quicker and easier to sail downwind with curved boards, dont gat caught up with all the discussion on shorter WL making it harder to sail with, the curved boards are never at an AOA that is having a negative effect of performance, unless you really screw up, but even then they are helping with your recovery from a nosedive etc.

The downsides are this:-

Added tooling costs
added production costs
you have to raise the windward board each tack/gybe to get best performance
there is a slight loss of righting moment, but the reduction in drag is compensation for this in the overall picture.

As to wayne's comment that the tooling cost is irrelevant... depends on the barrier to entry point, if the tooling is going to cost 15k (more than the hull tools) then its a big issue to factor in to the build costs. and I dont see anyone with F16 numbers in the 300's Hell even the Viper numbers are inflated and they are claiming 160 after 4 years production... makes the ROI seem pretty bad for a board tool. every now and then someone claims that their sisters uncle's neighbour can make a curved board tool for 20 bucks... but in reality its just an expensive thing to make a production quality tool for these things,



________________________
http://aus300.blogspot.com
--Advertisement--
Re: F16 and Curved Boards [Re: macca] #232965
05/30/11 10:52 AM
05/30/11 10:52 AM
Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
Seeker Offline
addict
Seeker  Offline
addict

Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
With all the variations of A cat curved boards being experimented with are there any "existing" A cat curved boards that could be fitted for use in an F16 effectively? $20 for tooling?...no but the $15,000.00 estimate is just as absurd on the other end of the scale. A CNC machine doen't care if its a curved board or a straight one.

Things get so ridiculously overstated on these forums...speeds, weights, costs...very rarely are things kept in the world of reality...and they think fishermen overestimate...obviously they never met a cat sailor.

Re: F16 and Curved Boards [Re: scooby_simon] #232966
05/30/11 10:52 AM
05/30/11 10:52 AM
Joined: Jul 2001
Posts: 953
Western Australia
Stewart Offline
old hand
Stewart  Offline
old hand

Joined: Jul 2001
Posts: 953
Western Australia
If you allow curved planks why not allow foils?

Still think this is all moot...


Re: F16 and Curved Boards [Re: Seeker] #232968
05/30/11 11:14 AM
05/30/11 11:14 AM
Joined: Jun 2001
Posts: 1,021
Australia
macca Offline
old hand
macca  Offline
old hand

Joined: Jun 2001
Posts: 1,021
Australia
Originally Posted by Seeker
With all the variations of A cat curved boards being experimented with are there any "existing" A cat curved boards that could be fitted for use in an F16 effectively? $20 for tooling?...no but the $15,000.00 estimate is just as absurd on the other end of the scale. A CNC machine doen't care if its a curved board or a straight one.

Things get so ridiculously overstated on these forums...speeds, weights, costs...very rarely are things kept in the world of reality...and they think fishermen overestimate...obviously they never met a cat sailor.


Try actually building the tools for a production run of curved foils, then after you have successfully built foils that are of the correct shape, twist and bend all the while not breaking in the kind of use that they need to withstand and then you can tell us all how much it really costs.

I bet you end up a lot closer to my estimate that you thought...


________________________
http://aus300.blogspot.com
Re: F16 and Curved Boards [Re: macca] #232969
05/30/11 11:41 AM
05/30/11 11:41 AM
Joined: Jan 2009
Posts: 5,525
pgp Offline
Carpal Tunnel
pgp  Offline
Carpal Tunnel

Joined: Jan 2009
Posts: 5,525
Sounds like a very nice cottage industry for a skilled craftsman.


Pete Pollard
Blade 702

'When you have a lot of things to do, it's best to get your nap out of the way first.

Re: F16 and Curved Boards [Re: pgp] #232970
05/30/11 12:01 PM
05/30/11 12:01 PM
Joined: Mar 2009
Posts: 932
Solomon's Island, MD
S
samc99us Offline
old hand
samc99us  Offline
old hand
S

Joined: Mar 2009
Posts: 932
Solomon's Island, MD
Clearly Macca is including R&D costs in his $15,000 budget, which I can see as being reasonable.

However, my estimate puts mold costs at <$5000, and it doesn't matter really if its curved or straight, twisted etc., just means you need to find a 5 axis CNC vs. a 3 axis CNC. How many out there have designed something and then built it? Namely how many have designed and built molds? I have and its not a trivial process. You need an aero engineer that knows what he is doing for the foil design, you need a solidworks or other CAD package guru to model the foil properly, and you need a mold guru to aide the CAD guy in tooling design. Then you need a structures expert to design a layup schedule that won't explode under sailing loads, which are hard to predict making his job difficult. Where you spend the money is important, you can reduce the production costs with good design work but often it is easier and safer with composites to build the piece, load test it and make changes to the layup from there. Of course this all has to be repeated to some extent if the foils are asymmetrical.



Scorpion F18
Re: F16 and Curved Boards [Re: samc99us] #232976
05/30/11 01:41 PM
05/30/11 01:41 PM
Joined: Sep 2005
Posts: 893
W
waynemarlow Offline
old hand
waynemarlow  Offline
old hand
W

Joined: Sep 2005
Posts: 893
Originally Posted by samc99us
Clearly Macca is including R&D costs in his $15,000 budget, which I can see as being reasonable.


So take the real world example of the Viper, $ 15000 / 160 boats = 94 bucks a boat for development and moulds to have the latest all singing and dancing board design intergrated into the latest design and to be one step ahead of your competitiors, seems a no brainer to me.

Nacra with their design knowledge should be first out of the start blocks. Bimare are already in a position to give an option with their design of case, DNA with their skills and design should be looking to expand their production in a Uni only boat, it is going to happen guys and sooner than what we think.

Re: F16 and Curved Boards [Re: waynemarlow] #232978
05/30/11 04:17 PM
05/30/11 04:17 PM
Joined: Feb 2005
Posts: 4,118
Northfield Mn
Karl_Brogger Offline
Carpal Tunnel
Karl_Brogger  Offline
Carpal Tunnel

Joined: Feb 2005
Posts: 4,118
Northfield Mn
People who are worried about their boats being suddenly obsolete, it will be eventually anyway. Curved boards or not.


I'm boatless.
Re: F16 and Curved Boards [Re: Karl_Brogger] #232986
05/30/11 08:23 PM
05/30/11 08:23 PM
Joined: Jul 2002
Posts: 539
taipanfc Offline
addict
taipanfc  Offline
addict

Joined: Jul 2002
Posts: 539
Firstly the curved board takes a lot more load. Due to its shape it is trying to pick the boat and its passengers up out of the water. The only production boats successfully picking a boat out of the water and keeping it above are the moths. McConaghy's in China can build the hulls very quickly, but lead times in delivery are delayed due to the time and engineering to make the foils. To get the required strength they put 500kg of weight on the foil when curing to help increase density and strength in the carbon. The finished foils are relatively light and you can put the ends between 2 benches and jump in the middle with minimal deflection. This is the level of tooling and manufacturing required to make curved boards work. The early foilers like Bladeriders would have the foils flex under the loads and this is effectively like having your leech flap upwind so would lose speed and power. The Mach2 under the method described just power forward in the gusts and reach incredible speeds. (33.8 knots peak is the latest top speed for a Mach2) Hence my comment in that it moves the class out of the homebuilder. Would certainly be a performance boost however to the boat.

Re: F16 and Curved Boards [Re: taipanfc] #232988
05/30/11 08:36 PM
05/30/11 08:36 PM
Joined: Mar 2009
Posts: 932
Solomon's Island, MD
S
samc99us Offline
old hand
samc99us  Offline
old hand
S

Joined: Mar 2009
Posts: 932
Solomon's Island, MD
I don't think this moves the boat out of reach for the homebuilder. Here's my reasoning:

1) I'm an engineer and can design a working curved foil solution if I feel like dropping the money to make it happen. I'd likely blow up a lot of boards and the performance may be sub par but it can be done.
2) I can just as easily buy a set of curved foils from a major manufacturer and fit them to my boat. Once again this may be sub par as board location and trim are critical. Granted several people in the A-Cat's are doing this with success.

As far as manufacturer support, I think it will happen. Enough big players have experience with the technology that the costs should remain reasonable and even if R&D is pegged at $30K and production of the boat is say 100, $300 per boat is still pretty reasonable for the chance to literally fly around the course.


Scorpion F18
Re: F16 and Curved Boards [Re: samc99us] #233020
05/31/11 09:54 AM
05/31/11 09:54 AM
Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
Seeker Offline
addict
Seeker  Offline
addict

Joined: Apr 2002
Posts: 695
Ft. Pierce, Fl. USA
People change boat designs and models in this class at an expense of a lot more than $300.00...one thing you can always count on is that things are constantly changing...every boat starts becoming obsolete the minute the design is finalized...

Things keep moving forward....doesn't matter how much you drag your feet....go with the flow or get left behind....affectionately called the "dead boat society" in the catamaran world. Look back and see just about everything we enjoy in the way of high performance sailing was attacked when it came on the scene. Wood hated fiberglass> Single skin construction hated Core construction> Cored Fiberglass construction hated Kevlar & Carbon > and the folly goes on….and on…and on…and on

Re: F16 and Curved Boards [Re: Seeker] #234994
07/20/11 10:57 AM
07/20/11 10:57 AM
Joined: Nov 2002
Posts: 465
FL
sail7seas Offline
addict
sail7seas  Offline
addict

Joined: Nov 2002
Posts: 465
FL
Quote from SA: http://forums.sailinganarchy.com/index.php?showtopic=105814&st=50

>Then we set the kite and left the boards fully down and Adam jumped on the wire, you feel instantly that the boat is lifting on the foils. Its very easy to get the whole boat out! We did this a few times and couldn't stop laughing! It's seriously the most fun you will ever have on a beach cat. For sure the full boards down option is not the fastest in the conditions we had (25kts by this stage) but it's a crazy amount of fun and very addictive..
Anyhow, sanity prevailed and we lifted the boards 30cm and tried again: This is the quickest I have ever been on a beach cat downwind. Pete was only just keeping up in the coach boat at full throttle. The slightly higher board setting still gives lift and the boat is semi foiling the whole time. You can feel that the steering becomes super sensitive and your speed increases as you keep the boat in the groove. It was around this time that I said to
Adam: "this is the future of catsailing" It's a whole new dimension to the sport, The added speed and feeling the boat gives you is something I want to do again and again. I would have stayed out all day if it was possible!<

Re: F16 and Curved Boards [Re: sail7seas] #235485
07/30/11 12:20 PM
07/30/11 12:20 PM
Joined: Jan 2011
Posts: 14
Lincoln, Nebraska
FRENZIED Offline
stranger
FRENZIED  Offline
stranger

Joined: Jan 2011
Posts: 14
Lincoln, Nebraska
I want straight boards. Don't wanna mess with hydrofoiling curved boards. Don't want to pay for the extra hoo-hah either. Simpler is better, IMHO.


LANDLOCKED
Re: F16 and Curved Boards [Re: FRENZIED] #235501
07/30/11 09:44 PM
07/30/11 09:44 PM
Joined: Feb 2005
Posts: 4,118
Northfield Mn
Karl_Brogger Offline
Carpal Tunnel
Karl_Brogger  Offline
Carpal Tunnel

Joined: Feb 2005
Posts: 4,118
Northfield Mn
Who is frenzied? Is this Select Sail?


I'm boatless.
Re: F16 and Curved Boards [Re: Karl_Brogger] #235510
07/31/11 10:01 AM
07/31/11 10:01 AM
Joined: Jan 2011
Posts: 14
Lincoln, Nebraska
FRENZIED Offline
stranger
FRENZIED  Offline
stranger

Joined: Jan 2011
Posts: 14
Lincoln, Nebraska
Originally Posted by Karl_Brogger
Who is frenzied?
Just some random human who likes to sail cats, and is recovering from college debt, and has no boat.

"FRENZIED" is in reference to the web-comic @ FRENZIEDminds.com


LANDLOCKED
Page 2 of 2 1 2

Moderated by  Damon Linkous, phill, Rolf_Nilsen 

Search

Who's Online Now
0 registered members (), 24 guests, and 93 spiders.
Key: Admin, Global Mod, Mod
Newest Members
toomanyhulls, madina9900, johngava, badcatsailor, wehnet
8119 Registered Users
Top Posters(30 Days)
Forum Statistics
Forums26
Topics22,397
Posts267,040
Members8,119
Most Online1,650
Sep 10th, 2019
Powered by UBB.threads™ PHP Forum Software 7.7.1