National 12 - find out more...
 
Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - Nigel W

#1
We are planning to come with Campervan. Hoping for sunshine and not too much wind.
Nigel and Chris
#2
We have in our possession a N12 Buff that was found in the men's changing room.

Many thanks to all those that helped in the running of the weekend, well worth attending
Nigel White
(contact details in the book)
#3
Ian

The DCB and Hijack were both designed for foils. In the case of the DCB, it is very slow without a foil. This is because the buttock lines rise so much over the last 1m of the hull, ie lots of rocker at the aft end. Without the foil the water flow can't follow the hull form and probably separates or gets very turbulent. The foil changes the flow pattern over the aft end and ensures the flow is attached, fools the water into thinking the boat is quite a bit longer and also provides lift at the same time.

The Hijack is not so extreme, but still has quite a bit of rocker in the aft end and also not much buoyancy.

The Chapter also has quite a bit of rocker, especially on the centreline in the last 60cm or so. Not much rocker at the first chine position which has almost constant rise from midships. If you look at your flow by the rudder, you will see the flow is not parallel to the centreline, but it moves in from the first chine at the stern to the centerline behind the rudder to generate a wave crest here. This is due to the large rocker on the centreline only. So this is why it likes a Chapter will take a foil well. This could also be the reason why a Chapter is quick upwind and possibly not so quick reaching (without a foil).

The Foolish, Numinous, etc all have very flat (straight) runs aft. Hence a foil will only provide lift and it won't change the whole flow behaviour in the same way as it does on a DCB, Hijack or Chapter

We sail a Chapter without foil and we can get amongst the DCBs on occasions, especially at club level. We do very well on the latest DCB handicap in fleet racing. So as always its down to sailing ability and most of the really quick guys are in DCBs or Hijacks and we are not in their league. As Tom says, the Thornton's have shown excellent speed with their Chapter, but they haven't been sailing that much recently. This is probably one of the main issues, no-one has really spent a lot of time with a foil on a non DCB or Hijack

Nigel 3445
#4
Andy
I'm not that Nigel.

We have found that a Chapter doesn't nose dive like a Foolish, Numinous or Wild Front Ear.  It is far more stable downwind, so we have had very few problems with nose diving. With our weight in the boat (16st) we found the Numinous uncontrollable in a blow on a broad reach, okay on a run, but you just needed to get there first, the bear away was really touch and go! With more weight in the boat it was much easier, this sinks the transom and makes the boat far more stable.

In the Chapter, we have found it much easier.  The first time we sailed the Chapter in a blow, the bow popped up, a totally unexpected experience in a 12. I still sit right on the transom, but don't feel as it I need to be 2 feet behind it.

Nigel 3445
#5
The fat rudder is there to provide extra buoyancy at the transom, so a boon to heavier weight crews. The fat rudder does not cause the big rooster tail in the wake, this is due to the shape of the aft end. The centreline has a lot of curvature over the last two feet, whereas the 1st chine rises gently towards the stern, hence the water flows towards the centreline from both sides to give your rooster tail. Its this shaping that gives the Chapter its good windward performance. 

Changing the fat rudder to a thinner one has no effect on the wake. I have a thin foil on 3445 at the moment having switched to this after putting a hole in the fat rudder. The rudders do feel different, I was constantly turning too quickly with the fat rudder, so the thin one has slowed down my tacks. The main thing with these rudders is to make them neutral otherwise they really load up in a blow downwind. At least you don't instantly capsize in a Chapter when the auto-release gives up! You need to turn the plastic cam to increase the release tension.

I wouldn't put a foil on the boat until you have learnt to sail it well and have it set up correctly. Then when you put on a foil, you will know that it is only the foil that is in the wrong position when you are going slow!

Burghfield open is coming up Mar 18th, a great day to sort out boat handling and starting with around 9 races in the day.

Nigel
#6
I (with Grahams help) have added some photos on the gallery of the rudder control system including Dares, dead cat bounce and paradigm systems
hopefully this link should take you there, http://www.national12.org/gallery/index.php?cat=10306
#7
Antony
In view of the early start, when is the 2nd race? is this after lunch?
Is it possible to camp (campervan) friday night, arriving late?
Is it also possible to leave the boat at the club for a couple of weeks?
Nigel and Chris
#8
Sorry but we also won't be there this year, have a great time. Hope there is some wind on the river all the time and the current is not too bad.
Nigel and Chris
N3490
ps we can recommend the supper and also the tea on sunday!
#9
The Whites will be there. Rosie in Eric and the oldies in 3490. Lets hope for another beautiful day.
Nigel
n12 Bottom Banner