Moulds

The moulds are the shape template for the boat. They're like cross sections at regular stations - that is points at right angles to the centre line of the boat. Full size patterns of one side of each mould are usually supplied in the plans. Its just a matter of draw a centre line on the mould timber. (anyting flat and thick will do - Mine is a mixture of 12mm MDF and 12mm ply which were previously moulds for my Dad's Thames rowing skiff) Then mark out the shape with a hamer and nail, or fancy spike thing for doing this job.


You turn the plan over and re-use the same holes to do the other side of the mould. The dot are joined up and then cut out with a jigsaw.

Everything is lined up on the strongback (building frame) along the centre line which is a string line running on top of the buidling frame. In the horizontal planeeverything is lined up with the level of the top of the building frame. The moulds are attached to the building frame to align with these two requirements. This is fiddly on your own. In this case the moulds are so close together its hard to get a screwdriver inbetween them.



Above are the first two moulds. I'm a tight arse and skimped on ply by not continuing the mould all the way to the building frame. I'm using bits of off cut.

Here you can see all the moulds in place. Having built them all I read that you can actually leave every second one out in such a small hull. Oh well. I plan to use light ply to minimise the weight so having all the moulds will prevent the light ply from sagging between stations.

After mounting all the moulds they are checked from all aspects with battenns to make sure the moulds are fair (smoothly curved). Bit of adjustment needed on the nearmost mould below.

Lastly the moulds are all held vertical by reinforcing one mould towards the front and one towards the back, then screwing spacers between all the moulds. By now its all really stiff which is good because attaching the boards will want to twist the whole thing.