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Chimera – Raid boat re-envisioned

A number of years ago, during the production of my Amity 20 design the then principle of Amity Boats asked me to design a “Raid Boat” to be rowed and sailed. A mould was professionally built to my design by Master Shipwright, Mr Ben Pluck of Piranha Marine. Amity produced one boat “Caladh” which was an open Raid Boat 5.5m long, 1.9m wide and a loaded displacement of about 530kgs.

Chimera 1
Chimera 2
Chimera 3
Chimera 4

Life changed direction and Amity Boats offered me the mould. The efficient minimum wetted surface hull design and quality build I could not pass up. I am afraid my days of using 7-foot oars to row 500kgs plus have gone from my perspective that is why outboards and efficient sail plans were invented.

Having explored the complete opposite end of the spectrum with our previous design which featured in AABB article “The tale of two Boats.” This design was about efficiency “MissUnderstood” is a great boat, extremely stable but high wetted surface means a larger sail plan required, a taller mast etc. With this design the minimum wetted surface hull shape lends itself to less sail area, a smaller mast section which, as I age, makes for easier set up. I developed further the “Sit-in” concept making maximum use of the available human ballast rather than hull form stability which “MissUnderstood” has in truck loads.

So “Chimera” was conceived. Cuddy cabin, huge, enclosed cockpit and twin shaft hung kick-up rudders. A pivot up swing centreboard and a multihull-meets-Hartley rig development of “MissUnderstood.”  The crew sit down in canter levered wings out beyond the original Gunwale. As rowing was no longer a requirement, I raised the cockpit coamings which became good back rests offering good protection. Aero-drag is not an issue. When sailing the crew sit forward immediately up behind the back of the cuddy cabin concentrating the weight in the middle of the boat.

The hull was female moulded up in our front driveway thanks to Steve, Rodger, Jim, Peter, and Gill. No gelcoat as it is heavy. Solid epoxy composite laminate, incorporating basalt woven cloth with products from Boat Craft pacific. Wet lay up using simple peel-ply no vacuum bagging extras. Wow that basalt is great stuff. I never did weigh the hull shell, but it would not have been more than 85kgs, so I was well on my way to accomplishing my desired 350 kgs light ship. I got close to the targets set.

Chimera 5
Chimera 6

Forward deck and cubby were built in plywood and basalt cloth set in epoxy resin. Built on the hull whilst she sat in the mould. I Raised the freeboard at the stem by close to 150mm and ran this increase in freeboard back to form up the backrests. The cockpit seats were laid up over temporary moulds in solid epoxy composite, incorporating basalt cloth. The cockpit floor is a ply basalt epoxy composite. Centreboard uses a fibreglass rectangular box spar with lead and glass composite skins. Not heavy but low centre of gravity with pork chop NACA foiled shape. A plug fills centrecase slot and acts as a fuse.

Chimera 7
Chimera 8
Chimera 9

For the rudders – I used a nice NACA foiled female mould I had built for our previous boat “MissUnderstood,” shortened them and installed fibreglass tube stocks. They kick up as per Open 60’s with the tillers connecting beneath the aft bridge deck which carries the radiused mainsheet track. Whilst not in vogue at present the mainsheet track radius matches that of the self-tacking jib.

The rig I based on “MissUnderstood’s,” and I utilized a nice little Procter Mast section I have been carrying around for 25 years. The mast required some customisation including lengthening but its light and short. A priority along with efficient plan shape was lowering the centre of effort. Short bowsprit and retracting. Little prod for ayso furling. The sails were built by Gary Saxby and crew at UK Halsey in Brisbane and are fantastic.

“Chimera” is my last build, which is why the designation 550ZX, my last with a full stop. So now we intend to enjoy her.

Chimera 10
Chimera 11
Chimera 12
Chimera 13
Chimera 14
Chimera 15
Chimera 16
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