Time to mill up some Queensland Hoop pine. This timber is straight grained and has no knots making it perfect for the mast.
I was fortunate enough to have a 5m length of timber thus eliminating the need to scarf timbers.
With my trusty triton workbench saw I milled up the 4 staves.
The two fore & aft staves measuring18mm x 57mm x 4877mm were cut slightly oversize. Then the two side staves measuring 18mm x 76mm x 4877mm were cut. The four sections were put through a thicknesser to clean up to the correct thickness.
Time to mark out the curves on the staves using the full-size cross-section drawings on page 3.
I started with the 18mm x 57mm fore & aft staves. The distances for the widths were plotted and two cut lines drawn along the length. I clamped the two staves together so I could cut the two staves in one saw run.
I used a circular saw to cut the shape and cleaned up to the line with a hand plane.
The same method was used for the 18mm x 76mm side staves however the taper is only on the forward edge as the aft edge is straight. I again clamped the two staves together and made one cut with the circular saw.
Using the bench saw I cut the first notches for the rabbets that secure the fore & aft staves. The saw blade was 9mm above the bench and 18 mm out from the fence. The second cut was 18 mm above the bench and 9mm out from the fence.
Careful measurements are required to ensure the width of the saw blade is included.
This shot shows the rabbets or notches, the two outside staves are the mast sides, and the two insides are the fore & aft staves, this is the base view.
And this is a top view.
The upper and lower blocking timbers are milled.
Time to glue the stave sections together. After some thought I decided to do this in two stages. The first stage involved gluing the two sides staves (Aft straight side face down) and the aft filler stave. My rationale for building the mast in two stages also allowed an anchor light wire and a power wire to be included in the hollow mast section. To reduce the number of wires and a bit of weight I will only install one earth wire and two positive wires.
I levelled up three sawhorses and two roller stands to support the mast level and at the same height for assembly.
Using all the clamps I own the three staves are glued and held together. The upper stave is located in place but not glued to ensure the correct box shape is maintained. Also the upper and lower blocking timbers are not glued in at this stage
The blue colored timber seen clamped here is to ensure the edge is kept straight until the glue dries.
Looks like the wife's car has to stay outside tonight.
Now it was time to run the electrical wires. As indicated earlier, I intend to only run three wires, two red positives and one black negative (which will be shared).
I needed to be particularly mindful of the exact location of the wires to ensure they won't be compromised when fixing the rigging hardware (don't want a screw going through and shorting out the electricals)
The difficult section will be the top of the mast where most of the rigging hardware is located.
After a lot of careful measuring, I chiseled a small tunnel along the SB side of the upper mast section.
Here is a close up of the chiseled section wetted out with epoxy. The tunnel is part in the aft stave and part in the SB side stave.
Time to insert the wires and ensure they hold in place until the plug is installed.
I mixed a small amount of thickened epoxy, spread it over the wires and into the tunnel. Using thin strips of timber covered in cello tape (to prevent sticking) and a few clamps the wires were pushed into the tunnel.
Here is an overhead view showing clamps holding the wires in place until the epoxy dries.
This view shows the wires glued in place. To ensure the fasteners for the upper pad eyes miss the wires they are glued into the side stave, whereas the fasteners for the shroud pad eyes are glued into the aft stave.
And finally, the upper mast plug is glued and clamped in place.
Clamps removed
Moving down the mast I glued in a 9mm block at the location of the mainsail throat halyard, just to beef it up a bit for longer screws.
And last is the lower mast block. I decided to exit the electrical wires out of the mast and level with the top of the dorade box. So, this involved routing a small groove along the lower block and exiting through a hole in the forward stave.
This pic shows the lower block glued and clamped in place.
The wires inserted and epoxied in place.
The forward stave is glued and clamped in place (sorry I didn't get a pic), This again used every clamp I own.
I left the mast clamped and secured to the levelled sawhorses for a couple of days to ensure the epoxy had well and truly set hard.
Time to make some dust, clean up the epoxy squeeze and level the faces of the forward and aft staves to the level of the port and starboard side staves. I used a handheld belt sander and went through three sanding belts. Unfortunately the belt sander left some high and low spots that will require some leveling.
The high and low spots are levelled and the edges rounded over with my hand-held router.
The sail track is temporarily fixed in place. I drilled 36 holes for the 20mm long SS round head screws. I removed the screws and injected a mix of epoxy and BoteCote's TPRDA into each screw hole. This will soak into the timber and harden the area for the screws. I also did the same for the 42 screw holes in the Gaff.
The next two pics shows where the electrical wires exit from the base and top of the mast.
Note how the wires exit off centre to allow for the fixing holes for the pad eyes.
Time to drill the holes for the mast hardware. All holes will be drilled, filled with thickened epoxy and then redrilled the smaller diameter for the bolts and screws. The mast pivot hole was a simple set up as it is square however.....
.... the set up for the holes in the mast head were a bit more complex to ensure they are even. I used the section that was cut off when making the curves for the staves and placed it underneath. This was checked with a level prior to drilling.
And it worked, the holes meet up evenly through the mast.
After filling the larger holes with thickened epoxy, I left them for 24 hrs. to harden up before drilling the final holes. The holes in the upper mast are drilled all the way through for the bolts and lock nuts.
And here is the mast pivot hole.
After all the hardware holes were drilled, filled and redrilled I gave the mast a thorough sanding.
Time to seal the timber, For the first coat I used "Bote- Cote" epoxy with a non-yellowing Hi UV resistant hardener. To ensure the resin soaked well into the pores of the timber I diluted it with 10% TPRDA.
While waiting for the epoxy to dry I screwed and glued a plywood plate on top of the mast for the LED anchor light.
The anchor light (or masthead light) is trial fitted. The original light was quite long so I cut the SS tube a bit shorter. looks much better.
To enable the multiple epoxy and lacquering coats to be applied to all four sides at the same time I adopted the rotisserie method (thanks for the tip from other builders).
(Pics to come)
