Depending on the size of the vessel these vary in thickness and width on the larger Yorkshire working vessels could be 5 inch by 3 inch but on the Peggy being a sailing coble they are much lighter at 4 inch by 2 inch, the top plank has a lot of tumblehome “means leaning inboard at top” this means a lot of bevel has to be removed to bring gunwhale flat at top, you can make a tool to help you determine this, rather than write a description a drawing and how to use accompany this page, but this can also be used on other parts where needed.
When fitting the gunwhales try to stagger the lengths on opposite sides of the vessel to give more strength, paint top 3 inches of plank and back of gunwhale before final fix. When steam bending the gunwhale timber is very difficult to set the cramps square, so to correct this we gut a block that will be square to the outside edge of the timber and cramp this to the frames inboard.
The base of this block is also square to the top of the timber this allows for the holding down position. If you don’t do this, due to the bevel on gunwhale, it will just keep rising up and jumping off the plank. See photograph for use of blocks. Don’t forget to leave length on the gunwhale timber to fit scarf joint, also on most cobles these extend past the transom to take the scut fixed on gunwhales across the back and above the transom. These often referred to as the horns.
When fixing the gunwhale the usual method is to drill the frame tops right through to take a 6 inch galvanized nail, but these are put in with the nail head on the inside this gives a stronger hold on frame top and will not split frame head top. On the outside these are plated over. Do the same with the drill as on fixing frames to sink the nail below surface. Don’t want any snags in way of net hauling.
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