This week is a continuation of the lofting exercise from the fourth week with more hand-on drawings on the 2.5 dingy. Leaving the table of offsets after the major references points and lines are drawn, I learn to use the tick sticks to cross references the points on my drawings of the half breadth onto the body plan. The drawing transom was also completed again projecting this time from the profile.
Key learnings are:
1) There are critical points of reference this dingy design which contain important details or information as to the shapes and overall structure of the boat. These are the butt 100, and 250.
2) The other critical reference points/lines for all boat designs are the Loaded Water Lines (LWL), the Chines (unless it is a round bottom boat), the deckline or sheer and Canoe body line as well as a ghost line (if there is a stem - in a stitch and glue design there may not be a stem). These lines give an overall image of the shape of the boat.
3) The table of offsets is used only in the initial transfer of the dimensions of the boat onto the drawing/paper. Once the basic lines are in, the table offsets become a minor document as further drawings are then taken off from the lines and drawings already made. This is where the errors made in the initial transfers from the table of offsets get "compounded" in the subsequent lines to be drawn. Intersecting points are taken from the profile for the height and from the half breadth for the width to determine where the referred points should be on the drawing. This is where the tick sticks come in useful. So from a two dimension drawing, I could draw out the "3th dimension" to transfer onto another drawing such as the body plan and the transom in this week exercise.
The fourth and fifth weeks have been quite taxing on my body having to drawing on the "floor" which is not something I usually work at that level. The working posture causes my back to ache. Maybe it was getting used to that posture but the fifth week is "more enlightening" than the fourth week (I was getting frustrated in the fourth week especially on the second day with my inaccurate drawing of the lines) as I was able to see "the light" after making the reference points/intersections between the various drawings of the profile and half breadth with the body plan and later with the transom. This is the most interesting highlight of learning for the fifth week. This fifth week is also a time I seem to be able to make judgmental assessment of whether my drawn lines were "OK" though not necessarily correct (as the errors I made earlier in the fourth week got "compounded" and lines went out of the measurements when I checked them). Nevertheless I felt at the end of the third day that I had learned the basic principles of lofting. This feeling shall be confirmed with the table exercise of the 7.3 yacht on the A4 paper in coming week. .
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