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Is there a 2D program that will replicate whole moulding?

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This is for a bucket list project that is a long shot at best.

Is there a 2D drawing or CAD program that includes the following functions?

The ability to select and place a compass center and use it to scribe an arc between two points on the circumference.

Draw a spline curve using three or more points -  probably a least squares fit  curve function.

The program would ideally be a hobbyist level cost or a cloud subscription sort of critter.

The 16th and 17th century ship designers mostly used a straight edge,  compasses - large and small,  and flexible battens.   
This limited quiver of tools is why those hulls had a similar shape.  Most current drafting programs seem to totally ignore these old methods.


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I’m not sure if I’ve understood what you’re asking for but from the description think this is probably standard fare in any normal CAD package. You can certainly draw points and use them to create arcs and splines in Fusion 360, which has a free hobby licence, and I expect the same is true for FreeCad. There’s a thread running on this forum called “an attempt to create a hull…..” or similar, in which we’re talking about various CAD packages, and the methodology of hull drafting, that you might find helpful.

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The programs that I have explored have arcs, but the function involves starting with two defined points on the circumference and connecting them.  This is no help for whole moulding.

Whole moulding - the center and one point on the circumference are the beginning  data that is input .    

Modern programs allow the center to be derived, but not used as a beginning.

I suspect that it is necessary to work thru the exercises in Anthony Deane's book to understand the tools needed.

The key curves on the profile i.e. main wale, etc.  have centers than are far above what paper is needed by a plan in its finished shape.   The one or two drawings of ships being drafted that have come down to us (M. Baker) show the draftsmen using large flat tables.  Which would be uncomfortable - backache and spasms - but a near vertical board would need to be impractical in height.

A computer would be much easier -  but what is needed is a function that starts with:  define center -  define point on circumference  - draw arc. 


Least squares fit curves are not a favored method either  as far as my past examinations have found.    What is needed is a math formula that simulates what a long thin wooden batten does to connect three points.  The math formula used to smoothly connect three points in the drawing programs that I have examined show far less restraint in possible solutions than an actual wooden stick would allow.

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