Mast bend on P-14/15s

TillyLucy@aol.com
Thu, 20 May 1999 23:27:44 EDT


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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Before the topic of mast bend slips away entirely (for the time being,
anyway), I think it might be of interest to sailors of the more modest Potter
to mention one of the nicer characteristics of the three shroud fractional
rig - Lateral mast bend.

Folks that have grabbed the end of their mast when it is lashed to the cabin
top have probably noticed that it doesn't take a tremendous amount of force
to move the mast end a couple of inches in any direction. Since, on the
P-14/15 the top portion of the mast is unsupported by stays or shrouds it is
free to flex in response to pressures placed on it by the sail. This means
that when a gust of wind hits the sail, the rig can serve as a sort of
"fuse", the top part of the mast will bend to the leeward side and back and
spill wind from the top of the sail - the part with the most leverage acting
to knock the boat over.

Using a vang to flatten the sail, as has been mentioned in several posts,
will tighten the leech, limit twist and interfere with this built in
"feature", thus it may be better to leave the vang slack under windy, gusty
conditions unless going downwind. Tightening the outhaul is effective in
flattening the sail, and tightening the main halyard or downhaul will move
the draft forward if weather helm is a problem.

Due to the four sided sail on the MkII P-14 and P-15s a backstay will never
be practical. Personally, I was a lot more interested in being able to
flatten the sail on my old dinghy, which had no features to allow reefing,
than I am with P-15 which does. These days, when the wind comes up the sail
gets smaller.

I love that little boat - it does so much so well!

Dave Kautz
P-15 #1632 Tilly Lucy
Palo Alto. CA