Mast Assembly

We have been experiencing a heat wave here in the UK which has greatly improved the viscosity of the epoxy and therefore its ability to penetrate the timber surfaces being glued. I have assumed that the mast will be subject to considerable forces in all directions and as such its structural integrity is paramount, I therefore saw this as an opportunity to construct the mast whilst the conditions were favourable. Rounding off and finishing can be done at a later date.

The architect recommends Douglas fir as a suitable species of timber for the mast and spars. Following prior consultation with my local timber merchants, I managed to obtain some top quality stock, perfectly true with a clear straight grain. I purchased sufficient for the whole job.

Handling 6 metre lengths of timber by oneself proved a little tricky, but I have a number of roller stands which proved essential. Four boards make up the laminated mast which I cut and planed dead true. Approximately three quarters of the mast is a hexagonal hollow. Because I have opted for navigation lights, VHF radio etc. I had to build in a duct/conduit to carry the cables to the mast head with the ability of pulling cables through at a later date if required. Through the solid sections I machined a 7 mm radius half round groove in each half then installed a plastic conduit supported in small plywood cradles down the centre of the hollow section. I was particularly careful to ensure there were no square edges to avoid any potential snagging during the process of pulling the cables through. During the gluing process I inserted a draw cord, when the mast was fully clamped up I tied a small piece of towelling onto the cord and pulled it through several times to remove the excess epoxy that had squeezed out into the duct. I continued this process at intervals during the curing time to be certain that the duct remained clear.

I have decided to terminate the cable duct just above the level of the Tabernacle. You can see that I have machined it in a slow curve to enable an easy cable pull through.

Note that I have recessed the plastic conduit into each end of the hollow section then rounded off the shoulder to prevent any snagging of the cables when pulling through.