Planking the hull 1, keel and sole.

It is my goal to have this hull planked by the end of July.

Since the planking is already cut on the cnc machine this shouldn't be too difficult except that before I can plank the hull I have to sheath the sole and garboard with two layers of glass cloth...and before I can do that I have to finish the keel.

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Fitting sole

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Fitting the sole.

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The sole is made from two pieces joined just forward of the centerboard case, the elongated slots forward of the joint are for the keel itself, It slots nicely over the centreboard case, I cut a v-groove all around the cutout to allow plenty of glue around the joint.

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Fitting ply doublers either side of the case, these will increase the width allowing room for required amount of ballast and also beef up the case side where the pivot pin will be.

Next is the keel

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The keel sides are clamped to the centreboard case and also located with small mortices into slots cut into the sloe. 

Each end has a "stem" a bevelled piece of wood that the sides are screwed to. The dimensions are in the plans. This piece is the first part of the building process that required any shaping with hand tools.

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Glueing the keel in place with a small fillet on both sides, a larger fillet will be made later

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After glue has set and clamps removed.

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Side view.

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View from aft and above showing hollow ends, the aft end is filled with high density foam the forward end with 120 kg of lead.

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The keel base is solid timber, a pattern for which is in each kit, I haven't cut the sheets with the pattern  in just yet so I just laid the wood in place and drew around it. The glue line in the picture is because I used some old Jarrah I had , If you are goung to use Jarrah on any boat then the keel is the place for it because it is very hard and heavy. I don't mind it being glued from two pieces as it will be well sheathed after.

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Cutout around the centreboard case.

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The outside also has "stems" whose dimensions are provided in the plans and which require hand shaping.

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Marked and ready for bevelling.

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Almost finished. Now the ends and base are removed to fit ballast and foam .

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The plans call for 120 kg of lead to be inserted into the forward end of the keel, I have several bars of lead of different sizes which I cut and planed to size.

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this piece for the front of the keel box

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Fitted in position

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I used a reciprocating saw to cut blocks, and also an electric planer for final shaping

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Lead shavings from the plane, these are used to pack around the ballast later, and any leftovers are melted down into a new bar.

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As more lead is fitted I use epoxy with glue powder mixed with lead shavings to fill the gaps

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As the keel fills I used clamps to prevent the keel from splaying as I pack the shavings and epoxy in 

I also need to finish the keel base. 

The cutout for the centreboard was finished with a flush cutter in the router, but this will mean that when I epoxy the base the insides will be a bit thinner than the case and will be prone to wear.Therefore I need to make the cutout a little bigger. First I use a radiusing bit in the router but one which rebates the radius a little,

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Slot as it was  after being routed flush with inside of centreboard case.

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Next with recessed radius.

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Then the plank is turned over and flush cut again with the bearing resting on the edge of the radius, leaving a slot approximately 1mm larger all round and a radius so I can lay sheathing cloth into the edge.

Centreboard and transom.

The transom is made from two pieces of 9mm ply, with mortices for frames cut into the inner sheet, these are slightly different sizes but when glued together with their top edges flush they assume the bevel required for the planking.

Both faces to be glued are sealed first, then thickened epoxy is spread on one face and they are clamped together, I used a few small screws to prevent them sliding around while the glue set, also I glued them in the morning so I could keep an eye on the mortices and make sure to clean out any glue that squeezed into them or else they would have been completely blocked with thickened epoxy, 

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Sealing the face of the inner layer of the transom, the thin slots are mortices for frames and must be kept clear of thickened glue , also visible are cutouts for the motor, boomkin, sculling notch and tiller

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Sanding the boomkin hole.

The two layers are slightly different sizes which gives a stepped  outer edge which gives the bevel for planking.

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Transom  is fitted by locating fore and aft frames into the mortices in the inner layer, these will be filleted later.

Centre board case.

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Sealing the inner face of centreboard case

Read for glassing

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After two layers of glass cloth and covered with peelply

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The spacers were also sheathed with two layers of cloth and then fixed to one side, but because they are radiused on two inner corners These corners had to be sheathed in-situ.

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When the glass had cured the box was finally glued together, Offcuts from the spacers are used to make sure the box sides are parallel while the glue cures.

Centreboard case finished and ready for sealing and fitting.

Setting up frames

With the building Jig set up the boat frames can be attached and the boat begins to take shape.

Battens for furniture as well as some doublers are fixed to the frames before assembly.

The frames are fixed to the supports with bolts, in this picture I am gently tickling the bolt in with my hammer.

With all the frames in place.

With the frames in place we then fit the transom centreboard case and longitudinal frames all of which like the frames have been pre coated with two coats of epoxy and sanded

The longitudinals all slot into the frames which stiffen the structure considerably but also confirm that everything is in its correct place

This picture shows one of the shelves in position but not sealed, I put this in to verify the position of the forward frames and also it helps to stiffen the structure but it is not fitted permanently yet as it makes access to the keel more difficult. It will be sealed, sanded and fitted before the upper planking is attached but for the moment i want to be able to fit the keel and more importantly the ballast without having to lean over too much

building frame

The plans include not only cnc cut parts for the boat parts and building molds but also the building jig itself so from the start all aspects of the construction are linked which helps prevent any errors in construction.

This accuracy did present problems at the beginning. 

The plans called for the building jig to be constructed from 15mm structural ply  from sheets 2440mm long, but here in Australia our home made ply is 2400 mm long and so I had to hunt around to find some imported structural ply.

I eventually located ply which was imported from Brazil, but whether because of climatic conditions or inaccurate manufacturing the sheets varied in thickness by almost  1mm.

Since the various components slot together with pre cut notches this meant I had to ease some of the notches.  

Using a piece of wood that  just fitted into the slot I used a technique called saw cutting to run a fine bladed  saw down the edge of the wood cutting into the edge of the ply

 I used a small test piece of ply for each slot and where necessary I finished off with a rasp.

The final fit.

The building jig consists of two long panels linked by individually shaped crosspieces which fit into slots at each station, these crosspieces will hold the frames.

In this picture I have  only fitted three of the crosspieces, the other pieces can be seen to the left, I have done this to leave the rest of the building frame clear to lay the actual frames on so I can coat them with epoxy.  

Frames laid out on building jig ready for sealing

The same frames with two coats of epoxy.

This sanding and sealing took a four days and was a little frustrating since I had all the components in front of me and was keen to start assembling but I wanted them to be fully sealed and sanded so they can be finished off when the boat is assembled without having to try to sand in difficult to reach places.

With the frames sealed and finally sanded I can begin assembly.

First the frame supports can be fitted and levelled

Using a string line to level the frame supports.

In the picture below I have bolted frame 8 to its support, I have omitted support 7 behind it and then used a sharpened stick to check my diagonals against support 6, this is to ensure the building frame is square.

Notice that support 6  has six bumps on its top edge to identify it. 

Checking diagonals.

Cutting begins

The CNC machine is finally up and running. Having spent a considerable amount of time building the machine and  learning how to use it properly then doing the final calibrating,  and now that its kinks and quirks have been ironed out cutting has begun!

Once the machine is up and running the various panels are quickly cut