First Mate Progress

As some of you may know, I have a First Mate under construction in my shed. I started her a number of years ago, with the aim of testing the panel developments for the design prior to releasing the plans for sale.

The significance of the need for testing when dealing with developed panel shapes in a stitch-and-glue design is that it is the size and layout of the hull panels which determines the three-dimensional shape of the finished hull rather than relying on an internal skeleton which has been carefully plumbed and shaped, and around which planking is laid.

One is built from the outside-in and the other is built from the inside-out.

Here is a carefully set-up hull on a strongback showing the stem, internal keel (or maybe keelson) and a large number of transverse molds around which the planking will be laid. In this case the internal structure determines the shape that the planking will adopt.

In this photo you can see the bottom panel of First Mate having the bilge panels attached using cable ties. The boat is already taking up a three-dimensional shape without any internal framework to help. This system relies totally on the accurate design, marking and cutting of the panel shapes.

This is the very same hull in a photo taken about ten minutes later. The topside panels have been attached with a small number of cable ties and the final shape of the hull has already been defined.

The fundamental difference between stitch-and-glue and any other sort of construction (with the possible exception of Birch Bark canoe building and some forms of Scandinavian "built by eye" lapstrake (clinker) building) is that it is the shape of the cut hull panels that determine the shape of the assembled hull, rather than the rigid internal skeleton as with a conventional boat.

Im not saying for one moment that one system is any better than another, but rather I am trying to illustrate why it is so critically important that stitch-and-glue hull panels be absolutely correct in their shape.

Hull panels for a scale model of Three Brothers showing how different the flat panel shapes are......

......compared with when the panels are assembled.

 Anyway, to get back to the First Mate that Im building, once the panel shapes were proven? to be correct, there was no urgency in finishing the boat. This may have annoyed my friend Ian Hamilton somewhat since the boat was being sort of financed by him. My boys and I have reluctantly agreed that she may end up being his boat (dont panic, Ian, she is yours...), but there were other things on the books which were more urgent, so First Mate sat in the corner of the shed.

Now the project is up and running again and here are a few photos: -

Foredeck glued into position after having been thoroughly epoxy sealed on the underside. There were three full coats of WEST System Brand epoxy used, with each subsequent coat being applied while the preceding layer was still chemically active, so that a proper bond was obtained. The deck was glued into position while the final coat was still tacky.

Centreboard case treated with epoxy.

Support beams for the stern sheets (aft seat) being treated with epoxy. The inside of the buoyancy compartments have already been treated and thoroughly painted with an epoxy primer/undercoat

Floor of outboard motor splash well glued into position, having been thoroughly sealed underneath

Aft deck being dry-fitted using silicon bronze screws. It was subsequently glued into position using the screws and additional silicon bronze ring nails

Aft seat (stern sheets) glued in after having been epoxy sealed. This view shows how much emergency buoyancy is contained in the sern compartments - this is exactly the same layout as in Phoenix III.

The two 12mm (1/2") plywood centreboard halves being laminated together with WEST System Brand epoxy. In the past I would have vacuum bagged such an assembly, but I lost my compressor in the January floods (the compressor drives the vacuum-generating venturi) so I have had to revert to standard methods. Note the large number of screws which help pull the two laminations together, along with clamps and lead weights. Most importantly, the screw holes allow trapped air to escape so as to give a good, solid bond. The screws are removed just as soon as the epoxy has set, which is the stage you can see in this photograph.

Rudder blade halves being marked out. Note how I have drawn the grid at full-size on the plywood.

Home-cut phosphor bronze plate used to spread the loads from the rudder gudgeon nuts. This is the lower gudgeon mounting viewed from inside the aft buoyancy compartment. It is only dry fitted at this stage, and will be set in bedding compound when fitted permanently.

Marking the top of the rudder blade lamination using a compass

Using a spline to mark out the gentle curves

Using french curves to mark the tight curves

Rudder blade halves spread with WEST System Brand epoxy prior to assembly

Rudder blade halves glued together over a strongback. Note the good squeeze-out, and just after this photo was taken there were bleed holes drilled in the centre portions

I dont know whether these step-by-step photo sequences interest people, so if you feel strongly one way or the other, please let me know. Eventually the website photo pages will get these pictures in thumbnail form, which loads up quickly, and allows you to enlarge only those which are of interest.

Related Posts by Categories