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.|