There is a way of doing it, but it requires a bit of guesswork here and there.
This is roughly how boat plans were drawn years ago before computers.
Print your drawings full scale (top and side views) line up the 2 drawings exactly at the transom
For the hull,- vertical measurements
Draw a straight line along the keel as far as you can (don't worry if the keel curves up)
Divide the side view into say 200mm intervals (for the bulkheads)
Measure up from your datum line to all points, (chine, deck etc,) (Do this with cabin later)
Transfer the complete keel shape/depth you require (up to the bow) to another piece of paper with the same datum line and measurements (by tracing)
Make the complete keel (I do it with a double ply makeup with a long slot built into the section for the prop shaft tube so it can be adjusted for angle)
Hull beam measurements
Do the same for the hull, taking in all points up to the cabin (plus whatever extra required to mount cabin)
Mark the bulkhead positions and measure across these points,- this will give you the top width of the bulkheads.
Take your side measurements, transfer them (along with the datum line, wider than the deck width) to another piece of paper, (draw a center line 90deg off the datum line and mark your measurements up the center line.
Extend those out both sides to the deck width lines dropped down to the datum line.
Draw lines from the keel out to these points,- ( this should give you a bottom shape)
This is where the guesswork comes in and a bit of experimenting is required. Cut your bulkheads to your drawing (they will be straight sided) then you will have to blend them to the required flare (if any) and hull shape.
I start with a 5x5mm spine screwed to the building board, over the greaseproof paper covered drawing, and notch the tops of the bulkheads to fit tightly in the correct positions. I then work with a length of 3x3mm balsa or spruce, to get the chine looking right, (look down from the top to check the curve ) When you are happy, mark these points on the bulkheads, (measure one side and transfer) You can then develop your required hull shape from the bottom up on one side. Once done, remove the bulkheads and transfer the shape to the other side.
Cabin sides can be copied directly and with the use of a few cardboard templates, can be built over the drawing as well. Quite a satisfactory result can be had. My HSL, Hartley, and a good part of the runabout were done this way. Hard to describe, but you might get the idea. The full scale Hacker plan might help.
JB
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