Category Archives: Participants

Finishing the backbone

In the last few month’s we’ve made loads of progress on the West Coast Skiff in GalGael. First we had to complete the backbone assembly. This is the central component of the boat and it’s pretty key that it’s well put together.

Traditional Boatbuilding Keel

Cat and Brian are happy about the backbone!

From our lofting we could pull the exact shape of not just the keel but the other parts that make up the backbone. In the picture above the stem, the front of the boat, is the dark piece on the left and the sternpost is the dark piece on the right. Both are made from Greenheart. The long straight section is the oak keel that we milled from the huge board. Joining the keel to the stem and sternpost at either end are the knees. These are both made from elm, the curving laminations follow the shape of the boat and ensure that they are sufficiently stong.

Bolting!

Cat and Brian drilling bolt holes for the stem.

Once we had all these pieces made we had to assemble them, they are held together with numerous 1/2 inch thick bronze bolts. Throughout this boat we’ll be using only bronze and copper fastenings, both these metals have different purposes but are strong and have the benefit of not rusting!

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While the keel was going together our dedicated teams of volunteers and participants were busy making the moulds. Each one of these is exactly patterned and shaped from the lofting to define the shape of the boat at a given position. Once the back bone was set up and ready the moulds stand on it at a given position, but first we have to set the keel up. And to do this we need a ceremony! About a traditional keel laying ceremony, next time!

Bending New Frames

Another few weeks have passed and everything has inched that bit further along. At the Tall Ship we’re deep into the process of reframing Starcrest. In order to maintain the shape of the boat we start by supporting the boat as best as we could. So we’ve block her up underneath; drive wedges up against the planking and support the hull from a beam built into the roof of the workshop. Inside the boat we have added bracing that runs across the boat, adding extra strength wherever we can. Then the laborious work of removing the frames begins, every second frame is taken out, each rivet ground off and driven out and the old frames cut out.

The exposed areas of the hull are cleaned up and inspected for damage, in many cases this has been the first time areas have been looked at in 90 years! So we’re alert to the chance of rot.

Then we are ready to bend in the new frame, we have a huge stock of fresh sawn green oak. This timber has to be totally straight grained and without checks or knots. It is milled to shape and has the corners chamfered, the chamfering helps to resist the tendency for the timber to start breaking away.

Each piece goes into the steam box for a set amount of time, the rule of thumb is 1 hour per inch of thickness, so the 3/4 inch frames get 45 minutes in the box. The heat from the steam softens the bonds between the fibres of the wood and allows them to bend so we need to be sure that the heat penetrates right to the heart of the timber of we risk it snapping. Wood doesn’t stretch, so as it bends the inside face compresses.

As soon as the piece comes out the box its hot and cooling fast, the guys have to work fast to get the piece into it’s finished place before its cold. It has to slither down between the hull and the stringers, so they push, pull and hammer it home. Using clamps, sticks and a pneumatic jack they push it to the right curve. And leave it to cool.

After it’s cool the no less laborious task of riveting it in has to be done, another task requiring team work and precision. But meanwhile there are fifty more frames to do, and that’s only half of them! It’s a slow job framing out a boat.