Thursday, 19 November 2015

Repairing bottom planking 1

Now that the main upper structure of Nanw was complete i.e. Frames, stringers and inwale all fastened she was sufficiently stiff to be turned over and put on trestles - she is quite heavy and it took three of us to turn her over safely.
The bottom planking has two areas of damage: A split in the second plank port side for about 4ft amidships and some stoving in on the starboard side - probably caused by clumsy handling on a trailer. Now, professionals would probably insist on replacing all the strakes full length but as this is a 'low value' boat and timber and copper is expensive, I intend to adopt a method I have used successfully in the past and scarf a new section in to each plank, staggering the scarfs.
Firstly, all the remaining fastenings along both lands were cut and driven out to beyond the damaged section and a line marked across chosen to miss the frames. Then a line of small holes were drilled and the keyhole saw used to cut across the plank. A chisel chopped the timber in way of the lands, inside and out, and the section was teased out. Scarfs were marked for a length of 3" on each end of good plank (a ratio of about 7 times plank thickness). Cutting them is a time consuming business in the boat, mainly using a 1" chisel. A small wedge opens the land to allow the scarf to be cut under the land.
Cutting across the plank. Sharp chisel used to cut out.
Section of plank removed - no going back now!
Cutting a scarf in-situ. A wedge is used to open the land.

Saturday, 14 November 2015

Inwales fitted and fastened

The new inwales were cut from some close-grained Douglas Fir and had some gentle tapering to fit snugly behind the existing breasthook and quarter knees that had been left in place. A beading was planed on the lower edge of the timber as had been done on the stringer below it. The inside face of the timber was given a couple of coats of wood stain/preserver and then clamped firmly in place and fastened all round starting at the stem and working aft. Once fastened through all the timber heads the  Jack Nichols was glued in place each side of the stem and the long copper nails through the breasthook, thwart knees and quarters were driven and fastened.
Inwales being planed down to sheer level.
Quarter knee re-fastened clamping inwale.