The Core Sound 17 is an easy to build stitch and glue plywood cat ketch rigged boat, using mainly 6mm ply, with some 9mm ply in the lower chine. Easily providing comfortable space for up to 4 adults, this fast dayboat was designed by Graham Byrnes, a naval architect now living in North Carolina but originally from Australia.
On a CS17 there are two masts, one set close to the bow, for the mainsail, and a mizzen, just aft of the center of the boat. The mainsail is larger than the mizzen. The sail plan spreads the sails along the length of the boat. The low center of effort afforded by the fore and aft, rather than upward, spread of sail, produces less heeling force.
Free standing masts require no rigging; making them quick to rig and unrig, easy to reef and inexpensive. They also offer an innate degree of safety: the masts bend during gusts, flattening the sail and de-powering the rig. It takes one person only a few minutes to rig this boat.
Following the instructions in the comprehensive plans, the various panels are marked onto sheets of plywood and cut out, and then laced together using copper wire, and pulled together into the shape of the boat. After a bit of time adjusting the way the panels lay against one another, the panels are then glued together using epoxy.
In a couple of weekends the initial hull had been cut out and glued. 9 months after starting, our CS17 was in the water. Stitch and Glue is a simple construction technique that gives great results!
She was built in a garage that is 5.2M deep and 4.9M wide. A verandah was added to the garage so that her cradle could be rolled out when access was needed all the way around, even when the weather was a bit wet.
Now that she is on her trailer, our CS17 fits diagonally into the garage, in an area 5.2M by 4.75, with a few centimetres to spare.
The hull was given several coats of epoxy inside and out. The hull and cockpit were painted with Aquacote (an epoxy based high build undercoat that is quite easy to sand and a polyurethane topcoat that is incredibly hard).
The deck has been painted with several coats of clear Aquacote, which has an ultraviolet inhibitor added to it. The Aquacote was largely applied by spraying, but the topcoats for the deck were applied with a foam brush.
The bottom chine, and half of the upper chine, were fibreglass sheathed, for extra durability. Rubrails, sprits and tiller have been finished in Deks Olje, an oil-based preservative that does away with the need to varnish the wood.
Auxiliary power is provided by a Minn Kota 50 amp electric outboard, which when running at full power will move Kirsty Ann along at a bit over 3 knots. Reducing power to 75% drops her speed to something less than 3 knots but more than trebles her endurance, allowing her to cruise for up to 8 hours on a single charge.
We have since changed over to a 2 HP Honda outboard motor. This allows us to travel further afield, and not worry about having to recharge overnight while away on sailing and camping trips. The Honda has parformed admirably, although being aircooled it is even noisier than a normal outboard. We do miss the quietness of the Minn Kota, particularly on river trips where the engine is used for long periods.
Advice and suggestions from other Victorian members of the Wooden Boat Association helped greatly during construction of Kirsty Ann. Find out more about the WBA Victorian Branch by going to their website at www.woodenboat.asn.au/
Another great source of assistance and inspiration was the B&B Yacht Design Builders Forum. Located at www.messing-about.com/forum, this forum has members from around the world, and can offer very detailed advice about building the CS17.
I've had several emails asking about the cuddy I made for our Core Sound 17, so I've added some photos and details here. Clicking on any of this series of photos will open a larger version of the image in a new window.
The frame is PVC electrical conduit, that I bent to shape by heating with a hairdryer. To get the right curve, I used the same jig that was used for bending the coaming. The cuddy is made from 4oz sailcloth that I had left over from making the sail for Rosamund. The channel that the sail runs through is PVC, made for fitting annexes onto caravans and the like. I could have sewn a boltrope along the base of the cuddy to fit into this channel, but the channel actually came with a piece of fabric with piping along one edge, to fit into the channel properly. I fitted this to the base of the cuddy. Because of the strong curve I found it quite hard to get the cuddy to slide into the channel, but eventually it was in place, and it hasn't moved since.
Three laces tie down the cuddy when not in use. To hold the cuddy open I run a strap from the middle of the cuddy frame to the mizzen mast, under the thawt. This keeps the strap out of the way of the mainsail sheets. There is a quick release clip on the strap, so putting the cuddy up takes no more than 30 seconds.
Sitting down at the tiller, I find that I can just see over the cuddy. If I want a better view I simply lean out a bit. The height was a compromise. I didn't want it to completely block my view forward, but it still had to be tall enough to provide decent shelter. As it turns out, it is great for our kids, Kirsty can just fit, and I have to crouch a bit to get under.
|LOA||5.2M (17' 0")|
|BEAM||1.78M (5' 10")|
|DRAFT||20cm – 1.06M (71/2" - 3' 6")|
|SAIL AREA||11M2 (119 sq ft)|
|HULL WEIGHT||158.75 KG – 181.5 KG (350 - 400 lbs)|
|SAILING WEIGHT||453.6 KG (1000 lbs) @DWL With people and gear|
|B&B Yacht Designs||www.bandbyachtdesigns.com|
At the Wooden Boat Association Christmas 2006 get-together, our Core Sound 17, Kirsty Ann, was awarded the WBA's perpetual trophy for the best wooden boat at the 2006 Melbourne Boat Show.
The boat show was held in July, but the WBA traditionally makes the award during our annual Christmas lunch.
Kirsty Ann certainly attracted a lot of attention at the boat show, along with the other boats from the WBA, but it was a pleasant surprise to receive the trophy!
About the builder
He has a reasonable collection of woodworking tools, but considers himself to be still very much a boat building novice.
He can’t build any more boats, as he has now run out of both workshop and storage space. He warns potential boat builders that it is an extremely addictive, and rewarding, hobby!