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Topmasts removedTopmasts & topsails in place

The main topmast and the fore topmast on Appledore IV were in need of repair. We brought them into the boat shop and decided that the main was in pretty good shape with the exception of a dry rot section near the bottom.
The fore mast was first cut with a circular saw
and then split with chisels and wedges.
There were enough bad spots in the fore topmast that we discarded about one third of the mast which will be rebuilt with Sitka Spruce.




Templates were made to match the tapering spar at defined points of every 3 feet along the mast.
A 2 X 8 X 20 foot and a 10 foot piece of Sitka Spruce were scarfed together to create a 24 foot piece from which we will cut the sections to form up the new section of the fore topmast.




The rotted section of the main topmast was cut out, note the scarfing jig in place.




The scarf was cut using the jig and a circular saw, chisels and finally a rabbet plane.     A 2" X 2" X 40" dutchman with matching scarf was then epoxied in place.
       
       




Other areas with minor rot were cleaned out with a saw kerf.

The main topmast shaped, sanded, and covered with two coats of epoxy. It is now ready for paint and varnish and to be returned to the ship.


Back on the Fore Topmast, side rails are epoxied and clamped in place to build up the radius but retain the hollow mast.
       




Bench Brush, the new boatshop cat, inspects the new section of the mast.




The final piece of Spruce is set in place. Shipping banding was used to clamp the piece to the existing spar. Wedges were then driven in to pull the whole spar tight.
       


Once the new section is squared a sparmaking jig is made. The purpose of the jig is to mark the flats of an octagon, creating lines for planning off of excess stock. There are several ways to figure the dimension for the jig; one way is to layout the largest diameter of the spar and measure the distance (2 x a). Another way is through math. An octagon is made up of 45 degree angles. As seen in the smaller drawing the distance needed is formed by the bi-section of that angle. The trig function of the tangent of the angle is equal to the opposite side (a) over the adjacent side (b or radius of spar). The tangent of 22 1/2 is .4142. So to calculate distance (a) multiply .4142 times the radius of the spar. Our spar has a radius of 3.625 times .4142 gives us distance (a) of 1.5 inches.
The corners were then planed off and the spar shaped using the templates made earlier.
The second spar was coated with epoxy and then both were painted, ready for return aloft.

The raising of the Spars!

The main topmast spar is raised by running a heel line from a fixed point atop the mainmast down through a block attached near the bottom the topmast, back up to a block at the top of the mainmast then down to a turning block at the bottom of the mainmast and lead back to a windlass.
Then lizards are attached at two points to the heel line first point slightly above the midsection of the topmast and the other near the top of the topmast. This way the topmast is raised from the bottom but with the top going up first.
A crew man waits aloft for the spar to pass through the top bail. At this point he attaches the rigging collar and the shrouds and blocks needed. The topmast is then raised to it's full height and locked in place on the crosstrees.
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