|
CENTREBOARD MEASUREMENT DIAGRAM |
| 1. |
The profile of the centreboard shall
comply with the diagram. When positioned over a template of the
maximum and minimum permitted profiles it shall concurrently
be not greater than the maximum nor smaller than the minimum. |
| 2. |
Except where otherwise shown the
datum lines for profile measurement are:
| (i) |
for width, a straight edge placed
against the trailing edge of the board. |
| (ii) |
for length, a straight edge placed
against the highest point of the board and at right angles to
the width datum line. |
|
| 3. |
The trailing and leading edges of
the blade between the limits of the top corner or radius and
the bottom radius, as shown on the diagram, shall be straight
except that concavities of not more than 2.5mm, which in aggregate
are not more than 150mm, are permitted. For measurement of width
any such concavities in the profile shall be bridged. The overall
profile shall be a fair curve. |
| 4. |
The shape of the cross section is
optional except that:
| (i) |
below 175mm from the bottom edge
the thickness shall be not more than 22mm. |
| (ii) |
above a line 250mm below the top
of the centreboard the thickness shall be 20mm ± 2mm.
It shall not vary by more than 1mm except that within 20mm of
each edge the board may be shaped to a thickness of less than
18mm. |
| (iii) |
between the limits in (i) and (ii)
the thickest part of the board in any section shall be 20mm ±
2mm.
If of hollow construction the thickness limits shall not be exceeded
if sub or super atmospheric pressure is applied at the drain
hole by blowing or sucking. |
|
| 5. |
A batten of wood or GRP, or stops
of wood, rubber or plastic, not less than 5mm thick shall be
fitted to each side of the top of the board. They shall be positioned
so that even if compressed no part of the board less than 50mm
from the top, except at less than 20mm from each edge, can enter
the centreboard case slot. |
| 6. |
The upper edge of the board may
be rounded. Any such rounding shall not extend more than 25mm
below the length datum line (see Note 2(ii)). |
| 7. |
A handgrip hole is permitted. It
shall be not more than 160mm across in any direction. No part
of the hole shall be more than 210mm from the top of the board
nor less than 40mm from the top or either edge. |