Saturday, 8 October 2011

Mast building

The masts are starting to take shape. Just before we set sail north this summer i had a good rake through all my Douglas Fir that has been air drying for two years now and moved it into the workshop so it would be good and dry for when I returned - and it is! Its amazing how fast douglas fir dry’s out - i reckon 6 months would have been fine.

I was going to use the bird mouth method but decided, in the end, to build them solid by laminating them. see the photo for the
arrangement of the staves. I had the staves cut to 105mm x 70mm which was for the maximum size of stave for the hollow birds mouth method. This stave size seems to have worked equally well for my new construction.I have taken the corner off the inside of the center staves to make a hole all the way up the mast to take electric / arial/ lightning conductor. You can see all the way up the one inch diameter 40 foot hole on both masts which suggest that they are remarkably straight so far!!

The timber I am using is native douglas fir locally sourced. This was cheep compared to imported timber but extra is required so you can cut out all the defects. The longest lengths i could get were 27 foot but after I had cut out all the bad knots generally they would end up at 20’ or less although some were used full length. In order to get the 39.5foot required for the main mast (36’ fore mast) each stave was made up of three bits scarfed together. All scarfs are staggered so you never get two next to each other.

Tomorow i hope to start the rounding process on the main mast........a good sunday job.

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