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Eclipse Sailing 1
Building the Hulls - from Keel to Knuckle

Building the hulls using bead & cove Western Red Cedar strip-plank over a mould consisting of 19 frames mounted on a strong back. The strip-plank shell is filled & faired using thickened epoxy and then glassed inside and out.

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Building the mould. 19 frames are mounted vertically on a "strong back" of 6" by 2" timber. I was lucky to pick up the frames from Howard, another Eclipse builder in the UK - see my Linksweb page.

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Levelling the Frame





Use of a scarf jig to rout scarf joints for the knuckle "gunwale"

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Mould ready for planking





Planking starts from knuckle with first plank glued and fastened with silicon bronze screws onto the knuckle "gunwale". The glue used is an expanding polyurethane glue called Gorilla Glue, the excess of which is easy to scrape off. Due to excessive twist on the planks as they approach the transom, a change of planking direction is required - indicated by the plank laid over the "shoulder" of the aft frames.

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Twist in Planks











Beginning the building of the outer stem laminated out of solid cedar and shaped to suit the boat. The outer stem is fixed to the inner stem.

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Finished Planking







The hull has had a coat of epoxy with gaps and gouges filled, and hollows faired, using epoxy thickened with Colloidal Silica.

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One Glass Strip







Three strips over keel and one layer of 600g/sq m glass cloth laid over hull down to the knuckle. The waterline and centre line are still visible. The position of the beaching keel and skeg was also marked on the bare wood and are visible through the glass. The centre line and keel/skeg positions has to be re-marked after 2 layers of cloth.

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Beaching Keel Jigs & Planks







Beaching keel shaped and filled -ready to be mounted on hull.

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Skeg finished







Both skeg and beaching keel attached to hull using thickened epoxy applied to join and as fillets, or beads, around the join.

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Cradle and glassed keel











The cradle is fitted to the hull. The idea is for the keel to rest on the ground, supporting the hull, with additional support being provided by the cradle. The design of the cradle should make the hull easy to move: the cradle is jacked-up taking the hull with it; pipes are placed underneath enabling the hull to rolled forwards or backwards.

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Ready for turning








The first hull is turned over with the help of friends and family. The metal hoops are the beginnings of a polytunnel to protect the kiln-dried wood from rain, blown beween the slats in the barn during winter gales, and to provide an enclosed area that can be heated.

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Owen planking








Richard scraping excess glue off inside of first hull. Planking of the second hull is now finished and it has been coated with unthickened epoxy and filled with epoxy thickened with Colloidal Silica.

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Mac marking waterline












The second hull is just like the first so there is not much new to photograph. So here is a cute picture of kittens in a woodshed. The farm has dozens of cats. The woodshed is next to the boatshed and these kittens are very curious about what we are up to.

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Sunrise with cow and trees






The finished second hull is raised onto trestles so the frames and strongback can be removed. The timber from the strongback is used to make the cradle to take the second hull once it is turned over. The first hull is now almost completely sheathed with glass cloth cloth wetted out with epoxy.

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View of inside of hull






The second hull in its cradle. We had 7 to turn it, but 6 would have been done: one at each end and 2 either side.

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A happy crew






Both hulls now glassed on the inside in four stages: one coat of epoxy over bare wood (plus thickened epoxy for gap filling & filleting), sand smooth then apply glass wetted out with epoxy, a light sand followed by 2 more coats. Hulls are now ready to receive bulkheads. The polytunnel has now been lined with bubblewrap to give more insulation.

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Building the mould.




Levelling the frames using the waterline given in the plans and marked on the frames.

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Scarfing jig.





Mould finished, ready for planking. Knuckle "gunwale" scarfed into one timber. Note inner stem laminated from 4 thicknesses of marine ply. A bevel has been cut into the knuckle "gunwale" to take the first plank along the line of the curve of the nearest frame.

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Planking











Even with the change of direction of planking there is still a lot of twist over the last two frames, so desperate measures are called for!

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Building the Nose







Planking and nose finished and sanded. Screws show the centre and waterlines, prior to marking them out.

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Filled & Faired





After a thorough sanding, the first of three 300mm glass strips is laid along keel, from stern to stem. Each strip has 3 coats of epoxy: one to wet out the 600g/sq m cloth, the next to fill the weave and the third to get a good finish. The first is applied using a stiff brush. the next using a plastic squeegee and the third using a roller.

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One Side Glassed








The beaching keel is a laminate of solid Western Red Cedar planks. The plans give the dimensions of the top and bottom planks. The thickness of the planks available meant 3 intermediate planks were required. Templates were made out of 6mm MDF board for all 5 planks. The templates were used to rout each plank. Once all planks were laminated together, shaping to the correct profile is easy.

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Beaching keel finished




The skeg is also a laminate of solid Western Red Cedar planks. The wedge-like shape is given in the plans, but it also has to be shaped to fit the curve of the hull.

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Skeg & keel attached to hull




The keel has now been covered with four layers of 600g/sq m glass cloth and faired into the lines of the hull. A cradle has been built to take the hull when turned over.

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Cradle fitting to hull



The hull is ready for turning over. Below the waterline has had 4 coats of epoxy mixed with copper powder in the ratio of 1:0.8 by weight. The copper provides a hard surface and provides anti-fouling properties. Above the waterline has been treated with 4 coats of epoxy mixed with a green pigment paste, in the ratio of 1:0.05 by weight. The colour is close to the final colour. Final painting and anti-fouling will be carried out just before launching (which seems a long way off!).

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First milestone









Planking on the first hull is started by Owen. Notice, the polytunnel is now finished.

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Richard scraping






Mac marking the waterline, to give us a level to work off when fitting out the hull. The waterline was taken from the plans and marked on the frames originally. When the planking reached the waterline, we marked it onto the inside of the covering plank. Mac is now "joining the dots".

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Farmyard kittens






I usually walk to the boatshed, along a river, over a disused railway track, past a sewerage farm (OK, this ruins the image, but I must be truthful) and through fields containing bullocks, cows or heifers. This is a photograph from that walk on a cold, frosty, misty winter's morning.

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Removing frames




The mould (frames & strongback) now removed and countless dollops of glue scraped off the floor! I found, when fitting the cradle, that the second hull did not have the same shape as the first. How could this be - the mould had not changed between constructing the first and second hulls? It finally came to me in the middle of the night! Freed from the mould, the hull was free to take a shape dictated by its internal tensions. The first cradle had been fitted while the hull was still on the mould. Phew! I haven't got an asymetrical catamaran. Build the second cradle identical to the first and all would be well.

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Second hull turned








A proud team of boat builders! From left to right: John, Richard, Owen & Mac.

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Both hulls finished