ORIGINAL: combatpigg
The chalk lines are like having an extra set of hands instead of floating a ruler is space while you consider how to interpret a complex shape.
So measure the chalk lines if you feel they're accurate.
So you crush the prototype model flat on the floor to get accurate lines on the garage floor? We both know you don't.
So how do you get accurate measurements of your "not on paper yet" model? Same way anyone would work out the measurements for anything, and that works just as good for the application.
A lot of what I build is design as you go and never gets formally drawn up until the design has proven itself.
The simple method requires a drawing of the wing, and requires interpretations of tip chord location and dimensions. Where would you get the dimensions for that simple drawing method?
The simple method requires a root chord, tip chord, LE sweep and half span. Same with geistware. What about the simple method makes it easier for you to come up with those? How does the use of a measurement make it more or less accurately taken beforehand?