chris vossel-newman wrote:
To compensate, for the additional wood (and better trim) I have removed all the tanks (both at the stern, above the waterline) with a longer term plan to resite the water tank in the bow area and, fuel wise, adopt the use of a 'day' tank and (later) the main fuel tank again forward and low.... I have already put in a 10 gallons fuel tank low in the stern behind the engine, as the 'day tank' and until the main tanks are fitted I will use 5 gallon containers for water/fuel.... But am I being overcautious?
Once in the water, I can move the ballast etc etc around to trim the boat, but is there any simple way of testing if the boat is underballasted or not ? someone said that, tied along side, you could tie a rope onto the mast and pull it towards the jetty and see how quickly the boat returns to upright ... is that how you do it? I am a bit unenthusiastic to try this with an un-stayed mast!!
Sooooooo, gang, as I aim to launch at the end of April I would welcome your thoughts/advice... capsize is not an option!!!
No, I don't think you're being overcautious. You're simply doing the sensible thing, in bring the weights to as central and low a position as you can. Bobtail has quite a lot of windage, and you'll certainly benefit.
When I worked at Kemp Masts, we always tested the rig on the first-off of a production boat class, by attaching the spinnaker halyard to a load cell tied to a pontoon, and winching the boat down past an angle of heel of 30 degrees. We could then calculate the righting moment, and compare it with that quoted by the designer.
The maximum righting moment of most modern boats is achieved at around twice this angle; at greater angles, it decreases until it reaches zero at an angle where the mast is well into the water. You can't haul down to this extent without down-flooding, so don't try. But it would certainly be a good confidence-building test to haul down to 30 degrees.