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Main Lower Mast:
Using
Plan Sheet 4
for reference, make up the main lower mast to the dimensions given as follows:
The lower mast is made up in two parts, the upper part is constructed from 4x4mm walnut cut to a length of 44mm.
The lower part of the main lower mast is constructed from 6mm dowel, cut to a length of 256mm.
The two halves can now be joined by drilling a 1.5mm hole, centrally down into the lower half, making use of the dowel
centring jig, and up into the upper half and gluing the two together with the use of a length of 1.5mm brass rod. Do not be
concerned by the variation in colour between the two different woods as this area is later painted dull black, the join is also
further braced by the cheeks and bibbs as applied next.
Offer the main mast cheeks (91) to each side of the mast and mark their position onto the mast bearing in mind the following
points:
1.
The cheeks should be directly opposite each other, i.e. parallel to one another.
2.
The cheeks should run 'inline' with the flat surfaces of the square top section of the main lower mast.
3.
The top edges of the cheeks do not sit perpendicular to the mast but have been pre-cut at the correct angle to
allow the main top, when seated onto this edge, to remain parallel to the waterline when the mast is stepped at the
correct rake
should run centrally (vertically) to the mast and, upon completion, the top edges of the cheeks should be flush
with the top of the 6mm dowel section of the main lower mast – the top edge of the dowel will need to be filed to
the same angle as the top of the cheeks to achieve this.
With the location of the cheeks marked onto the main lower mast they should be removed and this area of the mast should be
sanded to a flat, running from 6mm wide at the lowest point of the cheeks to 4mm wide at the top. If point 2, above, has been
followed the dowel will form a flush fit, both sides, to the 4x4mm upper square section.
Note: The fore-and-aft diameter of the dowel will remain 6mm; it is only the sides of the mast against which the cheeks fit that
should be tapered as shown on
With the main lower mast correctly tapered the cheeks can be fixed into position. If the top edge of the dowel section has not
yet been tapered to follow the top edge of the cheeks this should be done now.
Offer the bibbs (92) into place on the cheeks noting that they form a flush fit to the cheeks on their top, forward and after faces.
When you are happy with their fit they can be glued into place.
Using
Plan Sheet 4
for reference, mark the location of the wooldings onto the mast. The wooldings and woolding hoops can
now be fitted using the same process as for the bowsprit.
Identify the main lower mast top platform (95), gunwale (96), crosstrees (69) and trestletrees (70). Using
reference, glue the gunwale to the platform and using 1.5x1.5mm walnut for the battens, glue these to the platform, within the
gunwale as shown.
Glue together the crosstrees and trestletrees as shown and temporarily position them under the top platform, within the lubber's
u
hole
. You should notice that the raised section of the trestletree extends up above the top surface of the top platform, this is
correct and these protrusions will form the bolsters and should have their outboard 'corners' rounded off as shown (Fig 002 &
003).
When complete, glue the crosstree and trestletree assembly to the underside of the top platform.
At this stage, put the main lower mast and top assembly to one side; do not glue them to one another.
Main Topmast:
(Photo 062) Using
Plan Sheet 4
The main topmast is made up in three (or four) parts, the lower part is constructed from 4x4mm walnut cut to a length of
44mm, the first 10mm of this remains 4x4mm square while the remaining 34mm should have the 'corners' sanded flat to form
an octagonal, 8 sided, length.
The middle section of the main topmast is constructed from 4mm dowel, cut to a length of 82mm. Mark, in pencil, the point
70mm from the base. From the base to this point (70mm from the base), the mast should remain round and be tapered from
4mm to 3mm along this length.
From the now 3mm diameter point, 70mm from the base, the next 8mm should be tapered from 3mm round to 4mm round
with the remaining length of 4mm continuing at 4mm diameter to form the hounds
Note: Alternatively the hounds can be formed from a separate 12mm length of 4mm dowel, tapering from 3mm round to 4mm
round along the first 8mm, with the last 4mm remaining at a diameter of 4mm.
The 'head' of the main topmast is a 22mm length of 3x3mm walnut.
With the three (or four) sections of the topmast formed they can be pinned and glued together with 1.5mm brass rod, again
make use of the dowel centring jig for all round section.
Note: The flat faces of the lower section and the 'head' must be in alignment on the completed topmast.
u
, determined by the locating hole for the mast in the keel. Referring to
Plan Sheet
4.
for reference, make up the main topmast to the dimensions given as follows:
The Main Mast
©
2006 JoTiKa Ltd.
Plan Sheet 4
Plan Sheet 4
u
(or see note below).
the cheeks
for
35
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