November 29, 2023

Calliope Girl 18

Wednesday

During the morning, I finished up the water tank mockup with the last two side panels, and the top panel.  I secured the long side panels with glue and screws, but used only screws on the top to make it removable.  Afterwards, using the measurements from the actual “tank”, I recalculated estimated volume, again averaging the volumes predicted by each of the two small ends’ dimensions.  I scoured the internet to determine how to calculate volume of an irregular polygonal prism, and worked from the resultant formulae.  To determine the area of each end panel, required for the volume calculation, I had to split the shape into a triangle and a trapezoid, then find the area of each.  Then I multiplied the resulting base area by the length of the tank (48″) to achieve volume.  This suggested an approximate volume of 54 gallons.  In school they always said they wanted to see the work, so I’ve included it here.

Next, I tested the fit of the mockup in the boat.  It took a minute to figure out the best way to manipulate the tank through the companionway, but it fit, and soon I had it temporary placed in the forward cabin, level in both directions.  Because the aft end of the new berth platform would be raised several inches to make it level (rather than following the not-level lines of the hull stringers, as had the original), there would be ample clearance between the aft end of the tank and the platform above, as well as at the forward end.  This would leave room for plumbing fittings, hoses, braces/supports, and general access.

For future reference, I made some measurements from the inboard edge of the tank to some constant reference points nearby, noting these to use later to easily recreate the position of the tank for permanent installation.

There seemed no better time to prepare the forward cabin, and also the starboard hanging locker, for the work ahead than now.  These areas featured a lot of widely-failing coatings, with large sheets loose from the hull and otherwise flaking away.  To begin, I removed the two lowest sections of the wooden ceiling from the v-berth, to expose more of the hull above the immediate working area, and because the new platform would require additional clearance at the aft end.  Then, I sanded all the surfaces to remove the paint as needed, and to prepare the hull in way of the new water tank’s proposed location.  I did the same in the hanging locker, first removing the two flimsy shelves.

In the main cabin, I pried out the wooden battery trays from each side, then ground the surfaces smooth and clean.  The trays came up without too much difficulty, though quite a bit of wood remained that I had to sand away.

Afterwards, I performed a basic cleanup to remove the worst of the detritus, and hoped that this would be the last of the major surface prep required in the cabin.  With that in mind, I planned a thorough cleanup of the space next time, so that I could begin to move forward with new work.

Total time billed on this job today: 7.5 hours

0600 Weather Observation: 23°. clear. Forecast for the day: Mostly sunny, 32°