Very few mizzen booms are high enough to
clear the plywood vane (1600mm above mounting tubes). I
feel the worst and only problem is when closehauled with the
mizzen boom sheeted in hard to centreline. Under these
conditions the vane is limited in its travel by hitting the boom.
The remedy is to set the vane up to the weatherside using only
half of its movements which is quite acceptable as most yachts
are virtually self steering when on the wind. Slight easing of
the mizzen sheets helps a great deal and you can also pivot the
vane aft in its clamp to 45° off vertical without ill effect
which will probably clear under the boom anyway.
The vane can be pushed down horizontal
in its clamp which is very useful when manoeuvering or gybing
or tacking. No matter what you do to the plywood vane you
cannot break its mounting casting, connecting linkage or any
other part of the gear. You can easily make your own vane
from 6mm plywood.
Experience has shown that backwinding effects
from the mizzen on to the vane when closehauled are unnoticeable
(the yacht's inherent directional stability no doubt help here).