Ligaya in Indonesia

Boat Building in Gili Air

We were anchored off the tiny island of Gili Air one overcast and rainy afternoon, and I managed to get ashore for a walk.

The island is one of a group, very close to Lombok, the next island to the east of Bali.

There is a sandy track around the perimeter of the island, and it had been my intention to circumnavigate the island, a distance of a couple of miles or less. However, I did not get very far, as I came across three traditional boats being built on the beach, and spent the rest of my time chatting with the builders.

All three boats were being built right on the beach. They were all a similar size; about 30 feet, and of a similar design.

What made it more interesting is that all of them were at different stages of build.

The boat builders here have developed a very unusual way of building their boats; they build the skin of the boat first and then add the frames.

Normally one makes the frames of the boat first and then you set them up on a jig in their respective positions. Once they are all in place, then you fasten on the planks that make up the shell of the boat.

Normally the boat would be built upside down. Such a technique requires the ability to draw the frames full-size; a process known as lofting. Then you really need a flat area to set up the frames accurately and once the boat is built, you have to be able to turn it over.

By building the skin first, none of these three steps is needed.


Planks are joined along their length using a tongue and grove joint.

Using a curious mixture of traditional and modern techniques, the planks are joined edge to edge using wooden dowels, called Treenails (pronounced Trunnels). These are hammered into holes drilled at regular intervals along the edge of each plank, with corresponding holes in the edge of the plank that is about to be added.

Treenails can make an incredibly strong joint. As the boat takes up water on launching, the treenails swell in their holes to become fixed very securely

Here are a few treenails laying in the bottom of the boat, awaiting their use.

In a concession to modern techniques, all the boat were being built with the edges of the planks and the frames, being glued in place using a slurry of epoxy and sawdust.

On this boat the beamshelf is fastened using the treenails and glue. No metal fastenings used at all.
On one boat they were fitting a hardwood top plank to the transom, ready to mount a pair of outboard motors. This was secured in exactly the same way, with treenails and glue.
Here you can see the treenails in the edges of the planks. The plank was hammered down almost into position, then the glue was applied to the edges. Once the glue was added, the plank was finally hammered home to its final position.
All the boats here have bows that are very fine on the waterline, but have considerable flare to keep down the spray. This means that the first few planks have a large twist to them.

Here two guys are getting ready to twist two planks to fit onto the bows of the boat above.

One end of each plank is held firmly in wooden jig. Long lever are hooked over the other end of each plank. They pulled down hard on the levers, to apply the first twist to each plank. The levers were held in place by a piece of rope.

If they tried to twist the planks to their final shape all in one go, undoubtedly the planks would break. To make the wood more flexible they steamed the planks.

A shipbuilder usually has a steam box especially for this process, but here, they made their own, by building a fire in the pit beneath the planks and a wet rag regularly applied to stop the wood from burning.

After an hour or two of steaming, the wood became ever more flexible, allowing it to bend without breaking. By tightening the ropes the twist was increased. The planks are allowed to cool in the twisted position and they retain that shape.

You can see that the lower two or three planks require a lot of twist in the bows of the boat.

It is only when the shell of the boat is more or less finished that they begin to add the frames and the floors.

They alternate frames and floors, and each overlaps its neighbour across four or five planks. This gives great strength to the turn of the bilge, but also allows shorter lengths of timber to be used.

They select timber for the frames that has a curved grain, following the shape of the frame. Once again, this gives great strength to the frame.

This technique builds a very strong boat without the need for too many deck beams.

The timber for the frames comes from the nearby island of Lombok. The planks themselves come from Sulawesi, where very large boats are still being built from timber.
There is a lot of frames and floors to be made; each one is made to fit in a specific location. They are again secured using treenails and the epoxy slurry.
The frames and floors are cut by hand, using no more than an adz.
It has to be one of the prettiest settings ever for a boatyard.
This is similar to the boats being built. It is a similar size and shape, although at least one of them was not going to have the traditional outriggers, rather it will rely on a slightly wider beam for stability.
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