CLASSIC SIX METRE NEWSLETTER

Mast Step: A stainless steel band under the mast step is required to take the force of the
diagonals. This arrangement will create a complete triangular space frame, distributing
the loads over a large area of the hull, thus allowing maximum rig tension. The lateral
deck beam structure in this area must also be robust.
With these modifications, the keel no longer has to bear the tension of the rigging.
3. Bow section: We favour a foil forestay with furler. Normally, we anchor the forestay
to underside of the stem.
Stainless steel furler mounting: It is important to ensure that it is fully installed before
applying full loads to the running backstays. This approach avoids loading the deck and
can be used even if the frames and the inner stem are not in perfect condition.
4. Decks and deck beams: A plywood sub-deck greatly strengthens the deck. The
original deck beams of wooden Sixes are not strong enough to withstand the loads
imposed by modern sails. The camber of the deck increases its strength. Compared
to a deck with a good camber, a flat deck will withstand less compression before
collapsing.
Comments, by Kimo Mackey
I consider it worth stressing the very significant increase in hull strength which results from
the topside planks being well glued to one another at the edges for the full length of the hull
Theo Rye very correctly points this out, but I wanted to emphasize how substantial is the
contribution to longitudinal strength of the structure.
Brion Pope’s “plywood ring bulkhead and diagonal tie rod solution” for opposing the
athwartship shroud loads is without defect structurally, but some of us may find this solution
less than ideal for application on a Classic 6mR (“plywood ring bulkhead?….I don’t think
so”). My objections to this solution are not only aesthetic but practical as well, because the
arrangement hugely restricts access into the bow of the boat (about the only place to store all
your clobber).
I used to believe that the ring bulkhead – diagonal tie rod solution was the only one which
could adequately resist high shroud tensions, but I have recently had experience with a very
good system done by Red Sky Craft (Kotka, Finland) on Henrik Andersin's May Be VI (and
also on Fridolin). In this system the "chainplate" consists of a series of stainless steel straps
(4-5 per side) which radiate far below the sheer strake/clamp and continue deep into the hull
(all the way to the bilge in a fanning pattern). The straps are through fastened as they pass
over each frame and they are also fastened to a stringer (not part of the original structure but
added to increase strength in the way Theo has recommended). In this system the diagonal
rods are not used so there is free unobstructed passage forward alongside the mast. As in the
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