Lofting the Delaware

Lofting began at the close of 2018 with our Apprentice For a Day (AFAD) Shipyard Program participants. Boy were we happy we had relocated to the warmth of the Bay History building for our task of plotting and measuring. Through the lofting process we were able to create a fair set of drawings from the offsets that were created from the scans taken in 2012 by the National Parks service. As we move throughout the two years of her restoration these drawings will help to keep us honest in our quest to bring her back to her glory.

Here are those offsets I mentioned. Notice they are listed in feet - inches -eights with all of the measurements taken to the outside of planking. These offsets were taken as is (no fairing) off the boat in 2012.

Here are those offsets I mentioned. Notice they are listed in feet - inches -eights with all of the measurements taken to the outside of planking. These offsets were taken as is (no fairing) off the boat in 2012.

First, we started with laying out our stations and waterlines creating the grid on which we plot our long lines. I am referring to the waterlines and buttocks, which are listed as the heights above and below the baseline(W0) and the half-breadths which give us the beam of the boat at designated stations. Usually these offsets are lofted full scale however we had to improvise due to lack of space so we opted to fair the lines half scale. These faired lines were then remeasured and doubled enabling us to update our previous set of offsets.

You will notice that both the profile and half-breadths are drawn here. WO is our baseline and our load waterline, this is where all the measurements are taken from (offsets are below or above this waterline).

You will notice that both the profile and half-breadths are drawn here. WO is our baseline and our load waterline, this is where all the measurements are taken from (offsets are below or above this waterline).

Once we had recalculated the measurements and updated our offsets we moved onto lofting the body plan full scale. The body plan is the shape of the vessel at designated stations if you are looking at the boat fore to aft or vice versa. I often tell people to think of bread slices. The body plan is crucial for creating the molds that give us the shape of the boat at these stations.

Our waterlines are horizontal with the buttocks running perpendicular and parallel to the center line. Our heights and half-breadths are then plotted where they intersect or land on these lines. A batten, which is a thin, flexible piece of wood or plastic is pushed against awls or nails at these measurements enabling us to create and draw a fair curve.

Our waterlines are horizontal with the buttocks running perpendicular and parallel to the center line. Our heights and half-breadths are then plotted where they intersect or land on these lines. A batten, which is a thin, flexible piece of wood or plastic is pushed against awls or nails at these measurements enabling us to create and draw a fair curve.

Participants are using the loft to pick up the bevels at stations 2, 5, and 7 along the sheer and our waterlines.

Participants are using the loft to pick up the bevels at stations 2, 5, and 7 along the sheer and our waterlines.

If you’d like to be part of the process and want to learn more please check out our website for the upcoming Delaware work days and how to registrar. cbmm.org/learn/shipyard-programs/

Hope to see you around the shipyard soon!

Jennifer (Jenn) Kuhn

Jennifer Kuhn