Second boat - which design?

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Andy Ashwood
Posts: 6
Joined: 03 Dec 2010, 13:20
Design: Nimbus 3

Second boat - which design?

Post by Andy Ashwood » 05 Dec 2010, 12:22

Hi All,

Ive just finished my first boat and Im learning how to sail now. However, being my first ever build, the quality isn't as good as it might be and the finish certainly leaves something to be desired. So, I thought I would build another hull using everything I learned from the first and try and come up with something competetive whilst I learn the art of sailing using my sub-par hull.

The lake I am sailing on is fairly sheltered inland water so Im looking for a design which goes well in light winds and is suitable for home building (my first boat was a glass over balsa Nimbus 3). In answer to these sorts of questions people seem to invariably answer "Triple Crown" but I was looking for something a little narrower and more specialised for lighter winds.

Cheers,
Andy

Hiljoball
Posts: 283
Joined: 06 Jan 2006, 00:47
Sail number: CAN 307
Club: West Coast Radio Sailing
Design: V8
Location: CAN
Contact:
Canada

Re: Second boat - which design?

Post by Hiljoball » 06 Dec 2010, 04:34

Hi Andy and welcome.

If you have not read this article, it is very interesting background on the class and has some charts showing max beam/waterline beam and other relationships for a number of popular designs.

http://www.onemetre.net/OtherTopics/IOM ... rticle.pdf

When you talk about a narrower boat than a Triple Crown, think about this. The middle range of beam in IOMs seems to be about 220 to 230 mm. The Triple Crown at around 185 is already at the narrow end of the range. There are a few boats that go down to 165 max beam, the Scharming MK8 is a narrow hull (I believe) See link to free plans below.

There are a number of plans available in the 180 to 200m range, that most would call narrow.
The Triple Crown is related to the very successful Widget, but is a little hard to build due to the flare at the bow.
Easier to build is the EMO (free) from Frank Russell.
http://www.frankrusselldesign.com/Plans.htm
My first IOM was a Triple Crown and it is a good all round performer. Good in light air, yet resists nose diving when pressed.
I have just finished an EMO and just starting to sail it. Initial impression is that is is a good performer as I am up with our best local boats on first sail, before tuning.

Also easy to build is Maximuss
http://smys.yolasite.com/plans.php

There are some other free plans available.
http://www.velarc.net/plantas_eng.htm#plantas_iom

For a small fee there is SKA, the latest design from Brad Gibson
http://www.bgsailsanddesign.com/lines%20plans.htm

Hope this helps

John
John Ball
CRYA #895
IOM CAN 307 V8
In my private capacity

Patrick Parisienne
Posts: 10
Joined: 01 Sep 2010, 09:04
Sail number: AUS 38
Club: Albert Park Model Yacht Club
Design: Obsession

Re: Second boat - which design?

Post by Patrick Parisienne » 07 Dec 2010, 01:15

In my opinion, don't judge designs solely on their overall beam width. The waterline beam is what you want to know....

For example, a narrow beam boat of 185mm may still have a marginally narrower beam at water level, due to its vertical like topsides.

My Obsession has a 230 mm gunwhale beam, but narrows significantly at the waterline, although still wider than the Topiko's and Pikanto.

My new BTL, is closer to the Topiko/Pikanto in concept in terms of beam, but with different volume distribution.

Jeff Byerley's new design Evo, is a moderately wide and powerful boat, but retains a relatively narrow waterline for good light airs performance. It has been an impressive boat, particularly in stronger breeze.

Cheers,

Pat

Andy Ashwood
Posts: 6
Joined: 03 Dec 2010, 13:20
Design: Nimbus 3

Re: Second boat - which design?

Post by Andy Ashwood » 07 Dec 2010, 11:16

Thanks for the input guys.

Having poked around on those links a bit I quite like the look of a Noux2 which although a bit long in the tooth seems to have a good name. I was also very tempted by the Scharming Mk8 but I think maybe thats a bit too wacky for a second boat :)

If I am making a mistake then let me know, otherwise I will get cracking!

Cheers,
Andy

Patrick Parisienne
Posts: 10
Joined: 01 Sep 2010, 09:04
Sail number: AUS 38
Club: Albert Park Model Yacht Club
Design: Obsession

Re: Second boat - which design?

Post by Patrick Parisienne » 08 Dec 2010, 12:47

Yep, the Noux 2 is a great little boat.

I must say that it is particularly quick in light to mid No.1 suit conditions, and generally good all round performer. I race against one regularly.

My only advice ( and this is my opinion only) would be to place the keel 10mm or so further forward in the boat, from what the original plans suggest. The boat I race against tends to neutral to slight lee helm on the wind (in light conditions), unless a fair amount of mast rake, and a relatively tight mainsail leach is achieved. This boat is well built, with good rigs, so I am confident in this observation.....

As long as the position of the centre of gravity of the keel bulb is kept in the original position, everything should be fine. The boat should be able to sail with a more vertical mast, and still seek out the breeze. If racing in predominantly flat water, and lighter winds, I think the ability for a boat to be able to seek the lifts, while not having to use a tight mainsail leach is important.

We have moved the keel position a touch forward on 2 or 3 noted IOM designs (cheap, and easy enough to do), for similar reasons,and never found it to be detrimental to performance.

Please keep us all informed on your progress.

Regards,

Pat

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