Building a Jarcat 6 - Part 2
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The chines were attached next. To cut the angle at the stem I placed the timber in the frame notches ,held it with clamps and then pulled the chine around frame 1 until it touched the stem. I was then able to mark a line parallel to the stem on both the horizontal and vertical faces of the chine.
 
The picture shows a temporary pine spacer placed between the stems holding them  the correct distance apart. This spacer was also braced down to the strongback to stop the stem bending during the marking and then the gluing process.
 
With the ends of the chine cut to the correct angle both chines were placed once again and clamped to the stem. A hole was drilled through both chines and the stem. This hole allows the insertion of a dowel when gluing. The dowel provides positive location and added strength to the join.
 
Finally the stems were glued into position.
 
Next the stem packing pieces were glued either side of each stem. I also added an extra block to each side of the stem from the aft of the packing pieces to the fwd end of the keel. This block was aligned with the keel edge of the stem.
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With all the longitudinals in place I commenced the beveling of the keels and chines. I find working with hand tools to be quieter, cleaner and definitely more controlled than working with power tools so my method to bevel the edges was to use a saw to carefully cut a line from the inside upper edge of the chine to the centreline on the keel ensuring not to cut the intermediate stringers. Cuts were made at the frames and about 300mm apart elsewhere. Faired lines were drawn along the chine and the edge of the keel joining the bottom of the saw cuts  Then using a SHARP hand plane remove wood to the bottom of the saw cuts. Finally a coarse file was used to smooth and fair the timbers. A straight edge is used across the keel and chines to constantly check the bevels.
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Once the keel and chines were faired I moved on to the forward shelves. These were made up as stated in the plan and positioned from frame 1 to the stem.
 
Next I faired the stem blocking pieces again using hand plane, rasps and files. The epoxy glue and filler blunts the plane blade after a while so you need to keep resharpening often.
 
I use a standard oilstone then follow up with a 1000 grit Japanese water stone. The water stone is easy to use and the edge produced makes for easy working.
 
On the matter of tools, I use saws with Japanese style teeth (sometimes also called shark tooth saws) - both push style with hardened teeth and pull style Japanes saws for fine work. I started using these saws about 15 years ago and they really are a pleasure to work with. My planes I have had for quite some time and when I priced them recently was surprised to see a small block plane marked at nearly $100. You can buy a cheap electric plane for about half that amount. Like most things you get what you pay for and if you are purchasing tools only to build one boat I suggest you buy economy tools that will probably last for the project (but maybe not much longer). The other tools I have been using are a couple of wood rasps and coarse metal files. I did try using Surform tools that I acquired years ago but the new blades I installed did not seem to stay sharp long once I started on resin and filler.
 
I also use a rechargeable electric drill (14.4 Volts) for drilling and driving. Having two batteries helps keep the job going. One of the most used tools up till now is a putty knife which I use to clean up glue joins and fillets. I made two filleting tools- one with a radius of about 15mm made from an old power hack saw blade and the other with a radius of about 20mm made from a cheap putty spreader. White vinegar is used as a clean up agent for all my epoxy work. It really cleans the unset epoxy off the tools well and I leave a plastic tub of vinegar handy so I can just throw in the tools ready for cleaning once I have finished with them.
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Once the chines and keels had been beveled it was time to start adding the plywood skin. I started with the stem inside sheet. I used a full sheet here - I have seen pictures of construction that show this sheet only going to frame 1. The plywood sheet was trimmed to a rough size and then offered up to the hull frame. The position of the chine and stringers was marked on the sheet and the sheet then cut to slightly oversize. Holes were also drilled for the attaching screws. The sheet was then glued and screwed with stainless steel screws to the frame.
 
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Masking tape was used on the down side of the forward shelf join and an epoxy fillet formed between the shelf and the ply skin. Once the epoxy had set it was smoothed and fibre glass tape added to the join to strengthen it.
 
The forward bridge deck beam was shaped at this stage and glued and screwed to the rim pieces.
 
I filleted joins in this front area as I went to ensure that I had the maximum working space I could get.
 
The inside skins were completed from stem to transom on both hulls. Butt joins were made between sheets. These were glued and screwed with 10mm countersunk head stainless steel screws. These protruded into the inside of the hull and needed to be filed and sanded off later.
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Whilst the glue was setting on the various planking sheets I made the centre board case as shown on the plan. This needed to be finished and installed before the outside skin was attached to the hull. The case has a layer of fibre glass cloth on its inside followed by two coats of epoxy high build undercoat and a finish polyurethane paint.

The case was glued and screwed to the chine and gunwale at the position shown on the plan. The outside of the case and the inner face of the outside skin were both given coats of epoxy, undercoat and topcoat prior to attaching the ply to the frame. As I had decided to construct the mini keel only one centre board case was required. . I added a shaped piece of cedar between the chine and gunwale on the other hull about halfway between frame 3 and frame 4. This ensured that the curvature of the outside skin was maintained.
When the outside skin was attached the front shelf join was completed to this skin similar to the inside skin. The chine edges of the skins were then planed back to the chine ready for the chine to keel planking. The only thing to watch here was that the inside of the ply skin needed to be painted in the front shelf area. Indeed the interior of this compartment needed to be completely sealed with epoxy-TPRDA mix.
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Once the skins had been finished and the joins planed flush - yes with my hand plane, rasp and file - the front face of the stem was flattened and a piece of coachwood glued and screwed on. This was shaped to the skin surfaces. I had to use some filler to fair the skins and stem cap.
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The inner stringer was attached to the forward beam and inner skin as detailed in the plan. Blocks were added at the forward beam to increase strength of the join.
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This was the stage I reached in November 2003. The hulls fully skinned with the inner stringers attached ready for the deck.
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The deck was built from the transom forward. The ply was glued and screwed to the frames and the inner stringers. To ensure that the scarf joints made good contact, I used a piece of pine covered in cling wrap on the down side of the deck. Screws were driven through the ply and into the pine. Ample glue was used on the join and when it had set the screws were removed allowing the pine to fall away. The screw holes were then filled with epoxy filler.
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When the deck was finally attached the under deck support beams were glued and screwed from the underneath. The forward end of the support beams is slotted and then glued back together. Silicon bronze nails were used to hold the laminations at the forward end together while the glue dried.
 
All the corners were now filleted and a length of fibre glass tape with epoxy resin used to strengthen the bridge deck to hull join from the forward beam to about 300mm aft of frame 1. The top edges of the under bridge deck supports were routed with a rounding over bit.
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The next job was to radius the chine and keel joins and to coat the whole boat with a TPRDA - epoxy resin mix in readiness for the fibre glass sheathing