Cadet/General Bouyancy question

General chat about boats
Post Reply
jules22
Posts: 90
Joined: Sat Jan 04, 2014 8:32 pm
Location: Gloucestershire

Cadet/General Bouyancy question

Post by jules22 »

My daughters Mk2 wooden cadet ( front and rear tanks) holds a huge amount of water when dunked, I had wondered about straping a couple of bouyancy bags in the open spaces under the side decks.

Plan being that the bags help fill up the big void under the side decks, that scoops up all the water when you upright the boat, so less water to bail out (theory).

However........ I do wonder if the extra bouyancy will make the cadet float much higher above the water when on its side,
making it hard for a child to get up on the dagger board !.

Anyone with any practical expierence of this ?, before the bank of Dad stumps up for a pair of bags.
Stephen Hawkins
Posts: 534
Joined: Wed Nov 04, 2009 11:41 am
Location: The much maligned Swindon Town

Re: Cadet/General Bouyancy question

Post by Stephen Hawkins »

You are right to be concerned, as it will sit higher in the water and be more likely to turtle, which will make recovery all the more difficult.

Compound that with the fact that the Cadet is not really fast enough for a self bailer to work, unless empty, i.e. when you do not need it.

People have often added side tanks to the original mk2 design and taken the opportunity to open the cockpit up by reducing the width of the side decks and therefore the tanks. But still the problem remains to some extent. Later marks dispensed with the rear tank.

My son had a very old Cadet Mk2 at SCSC with no self bailer. The bottom line was, stop capsizing, or learn to get over the side onto the centre board before you reach the point of no return. This he eventually got down to a fine art.

Its getting a bag that is long enough, not too wide, as you do not want to encroach into an already small cockpit. And you have to factor in the thwart. Do you put the bag above or below it.

Might be worth just putting a smaller sail on and reducing the likelihood of a capsize in the first place.

regards

Steve
Steve Hawkins

1967 National 12 2383 "Sparkle"
Rupert
Posts: 6255
Joined: Thu Sep 16, 2004 8:40 pm
Location: Cotswold Water Park

Re: Cadet/General Bouyancy question

Post by Rupert »

My memory of the old style side decks was that the waterline was below the edge of the deck when capsized, so the boat came up dry. Old man faulty memory of teenage years?!
Rupert
jules22
Posts: 90
Joined: Sat Jan 04, 2014 8:32 pm
Location: Gloucestershire

Re: Cadet/General Bouyancy question

Post by jules22 »

A mark 2 defo comes up full of water ! (big bucket needed to bail), side tanks would be ideal ( mk3 conv !) but no time to do as it is sailed every week.

Rather than blow up bags , I might experiment with foam insulation cut to fit the available space, duct taped together and straped into the cadet with 25mm webbing.

I have most of the bits kicking about , so not the end of the world if its no good.
jules22
Posts: 90
Joined: Sat Jan 04, 2014 8:32 pm
Location: Gloucestershire

Re: Cadet/General Bouyancy question

Post by jules22 »

Anyone know if Celotex ( foam insulation with a foil backing) used in house building takes up water ?.

A mate who is a builder has some off cuts going begging, but not sure if it "soaks" up water over time. :?
User avatar
jpa_wfsc
Posts: 1188
Joined: Sun Dec 04, 2005 9:52 pm
Location: Oxford (Work) Coteswold Water Park (Sailing)

Re: Cadet/General Bouyancy question

Post by jpa_wfsc »

If you make the cadet float very high when on its side smaller crews will definitely struggle to get up on the board if they are in the water and it will turtle very quickly - but if you feel they are nimble enough to go over the top on capsizes - then that will not be a problem. A mast head float (until they have got the over the top style sorted) will avoid you spending your afternoons de-turtling graduates.

IS Celowhatsit an expanded polystyrene type? It will not absorb any water, but, will trap water against any surface it is held close to. This will promote rot. Bags are probably better as they will give more airflow around them to allow the surfaces to dry. But as you say - you have the foam insulation available to experiment with so go ahead - maybe remove it at the end of the season?
j./

National 12 "Spider" 2523
Finn K468 'Captain Scarlet'

British Moth, 630, early 60's 'Pisces'

!!!! Not CVRDA !!!!
Comet Trio - something always ready to sail.
User avatar
Ed
Site Admin
Posts: 3486
Joined: Wed Sep 01, 2004 10:11 pm
Location: Plymouth
Contact:

Re: Cadet/General Bouyancy question

Post by Ed »

I don't think celotex will work well.....

although it is closed cell and hydrophobic.....I still suspect it will absorb some water and it is just pretty horrible stuff.

Some of the other foams would be ok, like jablite or jabfloor which are expanded poly boards, or the blue/pink stuff which is used for flooring. They both cut and can be shaped easily enough. the problem with the celotex is that it brakes up too easily and the surface is softish and comes off on your hands like a kind of 'grit'.

Best wishes

eib
Ed Bremner
CVRDA


Jollyboat J3
Firefly F2942
IC GBR314 ex S51 - 1970 Slurp
MR 638 - Please come and take it away
Phelps Scull
Bathurst Whiff - looking for someone to love it
ent228
Posts: 228
Joined: Thu Nov 27, 2008 11:32 pm
Location: Stoke Gabriel, On the Dart, South Devon

Re: Cadet/General Bouyancy question

Post by ent228 »

Celotex has glass fibre reinforcement. It is really itchy and horrible. I have used loads of it.

However if it is available then if you were to wrap it in tape then it might be a good idea. Maybe cut pieces to fit into Rubble sacks and tape the whole lot up?
Nessa
Posts: 2290
Joined: Sat Sep 27, 2008 3:16 pm
Location: East Angular

Re: Cadet/General Bouyancy question

Post by Nessa »

I have a Cadet. The best solution is a mast head float and a pair of big hailers, plus a bucket in the safety boat.
The Peril
Agamemnon
Lovely little Cadet
OK 1954
Xena Warrior Princess
Finn 469
Laser 2
Wayfarer World
Post Reply