Junior Class Dinghy "Deca"
- a Kadett (Training) Dinghy.

Principal dimensions:
        L.O.A.       3.04 m  (10' 0.0")
	Beam         1.42 m   (4' 8.0")
	Sail area     4.5 m2 (48.5 sqft). 

The name "Deca" derives from the Metric pre-fix 'deca', which denotes a factor of 10 - the dinghy is designed to be just short of 10 foot!

The hull type is single chine. Somewhat like a dory type but instead of a flat bottom there is a Vee-bottom. This makes for a very simple build, no tortured ply, just simple curved panels that go together stress free for builder and ply alike.

The waterline is maximised by a stem that just slopes back a little and a flat run and decent sail area should make her plane very easily and without fuss.

The long side seats are level with the gunnels and enclosed to form buoyancy compartments. More buoyancy is provided by the forepeak box and all these spaces have access hatches so one can stow a few useful bits safely.


Material: 6mm (1/4") Marine plywood
Method: Epoxy stitch and glue (taped seam)

The hull shape is as for the "Dorita", but with a finer entry. There is also a deeper-Vee to the forward section. The hull is easily built and even a first time builder will have quick and satisfying results.
Internal fit out is kept to a minimum, this of course helps to keep the boat light but it also saves on building time. Enclosing the side seats does not add a lot of plywood and thus weight, but gives piece of mind should you capsize.
The ply/epoxy "Deca" weighs about 42kg/93lb when built with Okume ply. Redwood ply or birch will be a little heavier.

Sail and rig:

For the "Deca" I chose a 'leg-o-mutton' sail that is attached to the free standing mast using mast rings. The rings are openable making it easy to attach the sail to the mast and easy to hoist.

The sprit boom that goes with a 'leg-o-mutton' rig makes handling even easier.

A Cat rig is anyway easy to handle and with the addition of a sprit boom there is no vang required and no boom to hit your head if you don't duck in time!

Deca06 The rig is very simple to build at home as it does not require expensive mast extrusions, just standard aluminum pipes. The mast is made in two sections joined with sleeve (a wooden plug).

By using a lighter walled pipe for the top section, there is a weight saving but more important it allows for mast bend as the wind strength increases, which helps to flatten the sail.

Another advantage is that the mast sections are short and stow within the length of the boat for trailing and while stored at home.

The rig shows good performance on all points of sail. There is a slight bit of difference on the tack where the main rest against the sprit. However the sprit-boomed main makes for a safe cockpit while used for recreational sailing!

The plan shows the arrangement of the long side seats and how slim the boat is! Good for speed... PLAN

Plan Prices
Please read my Ordering Guide
Plans for this dinghy consist of two A0 (44"x33")sheets and one A1 (33"x22") sheet and detailed building instructions.

This set of plans is suitable for lofting all your own hull panels, bulkheads and all other parts.

Plan costs:
53 (+/-US$60) - which includes 13 admin (shipping) and entitles you to the building of one boat.

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