Centreboard Installation

While I was sealing the ballast tanks with epoxy I realised that it would be much easier to install the centreboard before gluing down the tank tops. There are holes for inspection hatches to allow the pivot bolt to be removed/replaced but it seemed like a good idea to put it all together the first time without needing to use the inspection holes. As it turned out there wasn't a problem and I could have done it through the inspection holes. Here is a photo of the plate hovering over the centreboard case.

The board pivots on a  25mm diameter bronze sleeve with a 16mm 316 stainless bolt through it to keep it all in place. Here is the plate with the sleeve and bolt.

With the board in place the swage on the lifting shackle sits up above the top of the CB case as expected. This will need a clearance hole in the CB case top and a pad under the turning block that sends the lifting cable forwards.

Last photo shows the retaining bolt in place. As usual the bolt is 5mm too short so that the Nyloc nut doesn't have enough thread to get a grip on. This can be fixed easily through the inspection holes when the ballast tank lid is in place. also on show in this photo are the epoxy fillets and multiple sealing coats of epoxy on the inside of the ballast tank/

Floor Panels and Ballast Tank Tops

 

I am installing two removable floor panels aft of the centreboard case and two forward of it. These panels are supported by rails around the edges and will be held in place by the catches that I described in an earlier post. The first photo shows the aft panel on the port side. The finger holes allow it to be lifted. The outer edge will be held down by the rim of the inspection hatch and by a small wood block in the aft corner (not yet fitted).

 

Here are the two aft panels in place.

There are six ballast tank tops either side of the centreboard case. These are made from a different ply with a browner colour than the removable floor panels. There are holes in the forward panels for inspection hatches to be fitted so that the centreboard pivot bolt can be accessed if necessary in the future.

The last photo shows the air vent for the ballast tanks on the port side, there is a similar vent on the starboard side. When the boat is launched the black plug can be left in place; this will prevent air leaving the ballast tank and so not much water (if any) will enter through the open port in the bottom of the ballast tank. If the plug is removed water will enter through the bottom of the tank and push the air out until the tank is full. Putting the plug back in will stop the water running out. When retrieving the boat onto its trailer the plug is removed and the ballast tanks drain as the boat leaves the water.

 

At this stage the ballast tank tops are loose. Tomorrow the inside of the tanks will be given multiple coats of epoxy to seal them and then bedded down in thickened epoxy to fix them permanently in place.

 

June 26th, 2013. Here is an update to June 24th's post. Yesterday was a cold day and the epoxy was slow to go off so I didn't get as far as expected. I also realised that it would be sensible to install the centreboard while I still had full access for fitting the pivot bolt. The result is that the tanks are still open.

 

Here is another photo of the vent pipe. it is made up from 15mm PVC pipe and fittings. From left to right: a threaded end fitting with all but 9mm of the thread cut off, pipe, 90 degree elbow, 45 degree elbow, threaded female fitting and a black threaded plug.

 

 

The Rudder

The rudder has been made up for some time and today I cleaned it up and did a trial run with the rudder gudgeons and pintles. Here it is fitted to the boat . The pie shaped piece is the drop down rudder blade which increases the underwater area.

 

 

I'm using a single long pin through the two sets of hinges and discovered that the trim strips on the transom prevented access for the pin. I have removed a scallop shaped piece of the trim strip so that the pin can be inserted and removed. Another problem was that the shoulders on the thick part of the rudder hit against the trim strips limiting the angle that the rudder can swing through to about 42 degrees either side of centre. I'm trying to decide whether that is enough or do I have to remove more of the trim strips to get 2 or 3 more degrees.

Here's another photo of the upper hinge.

With the rudder in position I wanted to get a feel for how long and at what angle the tiller needed to be. I like to sail standing up when possible  so the tiller needs to be a bit higher, Here it fits nicely in my hand.

Sitting down the tiller needs to be lower so I will arrange for a few degrees of movement to cater for these 2 positions.

I could have sailed the boat out of the shed and down the street! This photo, with me sitting in the boat, might give some idea of the overall size. I'm pleased to see that I wont need to duck as the boom goes over from side to side, it will clear my head with room to spare.

Remaining Spars Complete - Well Almost!

Over the last two days I have completed the two booms and the two gaffs. This involved adding the jaws to all four spars, rounding the corners of the spars (they are square in section with a radius on the corner) and adding the "B" blocks where needed. There is still a bit of sanding to do -there always is!

Here are a couple of photos of the main gaff and boom. When the boat is sailing the mast will be standing up, the gaff will be raised supporting the top of the main sail and the boom will be about at the level of the folded down mast. There will be plenty of clearance above the heads of people sitting in the boat.

 

 Here are the mizzen mast and the mizzen gaff and boom. I have made the jaws on the boom longer than the plans suggest to allow the boom to fold up parallel to the mast. This is not necessary when sailing but it will allow both spars to fold up along the mast and the sail to be wrapped around them for trailering. It will be an awkward bundle to pick up and stand in place at the transom but should be doable. This will make rigging and derigging the mizzen much quicker than if it has to be assembled each launch.

Main Mast Finished

I have finished shaping the main mast and glued the "ears" that support the standing rigging in place. I guess the next step is to apply some finish to the mast but I will probably leave that until the rest of the spars are done. Here is a photo of the mast in the boat.

 

Yes. that's right, the mast is in two pieces with a hinge so that it can fold down into this position for transport. There is an earlier post about the folding mast with reasons for doing it and photos of the hinge,

 

The next photo shows that the end of the mast sticks out beyond the transom by about 400 mm, I will make a more substantial support for the mast (plus the boom, gaff, sail and rigging) to use when transporting the boat on its trailer.

 

Rudder Hardware

I wanted pintles and gudgeons that were more substantial than the ones that I could find in the chandleries. These are intended for small dinghies and probably work but they don't look very strong to me. I designed my own and had them made up from 316 stainless steel by a small company that specialises in marine stainless steel fabrication. Here they are, 25 x 5 mm flat strip bent to shape with a single long 10 mm diameter pin to ensure alignment of the hinges.

Nicely polished and I will drill the holes for fixing screws when I mount the hardware on the rudder.

Latch for Cockpit Floor Panels

Over the past couple of weeks I have been preoccupied with other things and only working on the boat occasionally. In between the other things I have been working on the spars because they have to be made and it makes a change from working on the hull which I must get back to soon. I had a few photos of the various stages of working on the mizzen mast as it went from square to round but unfortunately the camera (and I) lost them somehow during the transfer to my PC; maybe they are still around but I can't find them. I will try and retake the photos as I shape the mainmast.

In between spars I have been testing out a couple of ideas for parts of the boat. One of these is a latch for the cockpit floor panels. I intend to have a floor at both ends of the cockpit rather than standing on the hull planks. This will provide a flat surface to stand on and a small amount of storage under the floor. The floors will each consist of two plywood panels either side of the centreline supported all round by rails on the bulkheads and seat fronts and another support running along the centre of the keel. Most of the time gravity will keep these panels in place but, if the boat ever capsized, some sort of latches would be a good idea.

While thinking about this I saw the perfect solution on another boat and so decided to test it out and also work out how to make it. Here are a few photos of the test setup.

Two panels with finger holes so they can be lifted. The button in the centre is about 50 mm in diameter and it can rotate freely around the screw in the centre. In this position it is holding the panels down and they can't be lifted. The button is flush with the floor panels so there is nothing sticking up to trip on or hurt bare feet.

 

 Rotating the button a quarter of a turn allows one panel to be lifted.

 

This exposes half the rail that supports the panels along the centreline.

 

Turning the button 180 degrees allows the other panel to be removed

This last photo shows the underside of the panel and the other part of the latch mechanism.

 

 

Making this little test setup took about 30 minutes. The parts are held together with hot melt glue, the button and hole in the panels were cut in one operation with a hole saw in the drill press. This exercise proved that the latch will work and helped me work out the proportions of the button and how to make it.