John M. MacAulay - Fernhaven, - Flodabay, - Isle of Harris. - HS3 3HA. Tel:01859 530340

Builder of the Hebridean`Birlinn` model

`COASTAL AND ISLAND BOATS`
continued..........

risk of breakage. After cooling the wood retains this new shape.

The complete hull shell can be planked up before any frames or ribs are fitted. The longitudinal stiffness created by the overlapping strakes. fastened with copper boat­ nails. is sufficient to maintain the required shape until the frames are added. In small boats, dinghies and other boats up to around thirty feet in length, where lightness and flexibility is desirable. steam-bent oak ribs are adequate. but for more robust service or for larger boats it is best to build with grown oak frames. The individual frame members are selected from natural crooks or bends that best fit the sections of hull to be framed They are marked from a template before sawing to shape with the correct bevel, and are stepped or notched to fit the strakes. They can then be nailed through and clenched. or galvanised dumps are driven dead into the frames. The spacing between frames also depends on the degree of strength required and, as can be seen in fishing boats from fifty to eighty feet in length, the grown frames virtually form a solid wall of oak within the hull. In open boats the thwarts or rowing benches are the members which impart transverse rigidity and have to be secured firmly at each end using grown knees, sometimes in pairs, which are riveted to the riser and the gunwale with heavy copper nails. The gunwale itself is secured in like manner at the bow and stern with grown breast-hooks and quarter-knees, closely following the required shape in the natural grain of the wood for maximum strength.

Watertight integrity depends to a great extent on the closeness of finish to each plank overlap or 'land'. The bevels must be extremely accurate and each strake has to be steamed sufficiently to ensure that there is no undue straining before the copper nails are clenched up tight. Normally a seam-dressing of..

Books by John MacAulay:
Birlinn, Longships of the Hebrides
(White Horse Press)

Seal-folk and Ocean Paddlers
( White Horse Press)

click on icon to view line
drawing of 19ft sailing boat

Glossary of Terms used
in this article