Building a Jarcat 6 - Making the mast 2
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Well next I had to cut the groove in back of the aluminium tube so I invested in a router bit suitable and tried to rout the tube using the jig as shown on the previous page. I was very hesitant about forcing the router and found that I was not making much of an impression on the tube. I then tried cutting the tube with an angle grinder and cleaning up the cut with the router bit. This worked fairly well, although very noisy and I was on the last 500mm with the grinder when I heard a "snap". the last 500 mm of the tube had parted from the epoxy. I guess the heat from the cutting had caused the epoxy to weaken and the track became lose. Lucky it happened now and not when sailing. Back to the drawing board. Grabbing the end of the tube I pulled it off  the back of the mast and then started searching for a track to screw to the back of the mast. I finally located a suitable track and ordered it.
Whilst waiting for the track I shaped a section of cedar to fill the half round previously routed in the back edge and glued this in with lots of epoxy. I then dressed the edge flat once more and when the track arrived glued and screwed this to the back of the mast. I made deep gouges in the aluminium face to give the glue something to "grab on to ".
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I engaged a local metal worker to produce the hounds in stainless steel and the rotating mast step in 4mm aluminium.
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The step is not the one shown in the plans and has been designed based on the step I saw on "Tuzanuff" - Vic Varley's Jarcat.
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I purchased two Riley spreader bases and shaped pieces of cedar to angle the bases at 15 degrees aft. These were glued to the mast. I then put a layer of epoxy filler on the wood base, covered this with "Gladwrap" and pushed the Riley base onto the "Gladwrap". This created a well fitting impression in the epoxy.
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Here you can see the mast head with the main halyard pulley bolted to a piece of aluminium channel.. This channel is recessed into slots cut in the central spar and a through bolt anchors it to the central spar. The aft edge sits on the cedar aft edge of the mast. The aerial and light wires were taken outside the mast and then sealed with epoxy filler.
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Here is the mast after a few coats of paint. I used the "Luxepoxy" undercoat but did not want the full gloss finish of "luxathane" so I found a satin enamel paint that was close to the colour of the top sides.
The aluminium tube spreaders have been added along with the hounds, mast step and spreader attachments.
The cover on the masthead was made from a piece of 10mm ply with a "skirt" of 1.2mm ply and then given a coat of fibreglass and epoxy resin. It is a push fit on the top of the mast.
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We stood the mast on the boat in the driveway. The first time we raised the mast we used rope to stay it while I marked the stay lengths on the stainless steel wire. We then raised the mast several times to check positions of the various pulleys and cleats on the mast and on the boom.

The day we were going to have our first trial with sails the hounds twisted on the mast and jammed the jib pulley so we had to travel by outboard. Probably lucky as the wind gusted up to about 20 knots and I was hoping for a lighter breeze to try the sails initially.

I added extra straps to the hound as shown here. Hopefully they can't twist now. I also added a piece of angle to the step as shown.
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This allows me to insert a shaped block of hardwood  between the mast base and the step to stop the mast rotating.

The only other problem I encountered was removing the bolt in the mast step hinge after lowering the mast. I think the threads on the bolt were catching on the aluminium and will use a smooth pin instead of a bolt in future.
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The boom was laminated from two pieces of cedar. An aluminium tube was embedded in epoxy at one end. This is where the gooseneck pin slides in. Once shaped the boom was given several coats of epoxy resin followed by Luxepoxy and painted to match the mast.
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The centreboard was shaped from 12 mm plywood and glassed with Uni directional fibreglass and epoxy resin. This was finished the same as the rudders.
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The tillers were laminated from pieces of rosewood.
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The circular blocks glued to the tiller arm are spacers/strengthening supports for the tiller axle. A slot was routed in the rear section to accommodate a pin (bolt) on the arm connecting the rudder boxes. A piece of slotted polycarbonate was added to this part of the tiller to provide better wearing.