Another handy tool

Here is some more pics of the planking.

Here I'm using the scissor jack again to line up a sheet.

All of this work needs a lot of screws to hold the sheets on while the glue sets and would be much harder without the use of this handy tool.

This is just like a cordless drill but without the troublesome battery, lower RPM and more torque than a standard power drill. 12V? 18V? try 230V, works way better and never goes flat :) The torque settings are great for putting the screws in fast.

Getting my plank on

Finally I get to start closing in the hull. One last look before it gets covered. This pic really shows the shape of the boat very well. I have found two new things that are taking up more building time, staring and daydreaming :)

I have prepared one side of the plywood sheets by coating with epoxy, sanding and coating them again. This gives a very nice smooth clear finish to what will be the interior of the boat.

You can see in this picture I am lining up the second sheet on the outside of the port hull. I am using a car scissor jack to have good control over the location of the sheet to butt it against the first sheet. Once in place, I put a few screws in and then use a pencil to mark the location of stringers and framing on the interior side of the sheet. Then I remove the sheet to prepare it for mounting.

Using the pencil lines as a guide, I cut out the shape (slightly oversize to allow for trimming), drill the holes for the screws and sand where the stringers and framing will be.
Then I apply epoxy to the sanded areas and to the framing/stringers then thickened epoxy glue over the top, then screw in place with a lot of screws and tidy up the squeezed out glue. Then the next day I remove the screws and get ready for the next sheet.

Inspection ports

I decided to put these in while access is easy.

I used this hole cutter which attaches to a drill. Then sanded the edge and applied epoxy. Once cured, I used marine sealant and screwed into place with stainless screws..
One port is in the forward bulkhead below the storage area and one is in the stern. Both areas serve as watertight bouyancy. With this boat, I want to be able to regularly inspect all areas.

Planking Prep

With most of the stringer fairing done, a few more jobs need to be done before planking begins. One of them is butt blocks for joining the panels. I will scarf the keel and inner wing but I have decided against scarfing the large side panels due to the size as I am building this all by myself so full length side panels would be too hard to manage. The butt blocks are made from the same 6mm Okume as the panels which I cut on the table saw which allowed me to quickly make a lot of them straight and identical in width.
I used a router to take the majority of wood out and also use a power file to tidy it up.

Then simply glue them in place. I will sand them as I go around the hull double checking everything is fair.

Fairing Stringers

Now that the stringers are all on, they need to be faired so that the outer surfaces will line up with the planking, and give a good surface for glue adhesion. For this I am using a combination of electric planer and belt sander. Checking as I go with a steel rule.

Making a Plank

To make the bottom of the boat appear as one continuous piece of wood, scarf joints are needed. With the fairly narrow width of the bottom of the hull it makes it an easier job for my first attempt at scarfing plywood.

So here I have some 9mm Okume and I have marked out from the end of the plywood lines to indicate where to sand to to give a 12:1 ratio angle. On the bottom is some 12mm ply to stop the lower piece from bending at the edge. This stack is all sitting on a large wooden beam to raise it off the ground making it easier to work. Then using a belt sander I sand to give the two pieces a matching angle, this is basically the same method I used for the stringers.

Then I lined up the lengths of ply with the laser level, glued and clamped. The result was a perfectly straight plywood plank about 7 metres long.

Stringers all on

Now that the stringers are all on, the shape of the boat is clear. Before putting the stringers on I found it hard to visualise the inner wing toward the bow as it is fairly complex how the angles converge, but it ended up being quite straight forward in practise.

Other potential KD650 builders will find this photo interesting. Locating stringer X at the stern. Using the laser level and a steel rule, x marks the spot.