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30' Sport Fisherman   Boat building project

design and build of a center console offshore sportfishing boat 


Computer Design

Now here's another area that I don't know jack about. But why let that stop me? Actually if you are contemplating anything more than a dingy or "pram" , what's that anyway?, you almost have to use a computer. That is, unless you what to take time to learn lofting which is a difficult skill. With computer design software you still have to design the  boat but what you get outputted is a smooth set of lines. The output for building can be  either in a table of offsets form or plotter for full size patterns of the sections.

I choose a program by Peter Rye and his Blue Peter Marine Systems Pty Ltd ,Australia. I can not compare this program to the others that are available because of the demos that I downloaded and tried this was the only one that I could even begun to make work.  You can buy the program for $100 for the (S) student version and upgrade for another $100 to the (G) slightly more enhanced version or you can buy the professional version for $500. I used the (G) version to get the plotter output ability. Actually I just built the hull from a table of offsets that the student version can do. Maybe for a round bilge sailboat the plotter output would save time in getting to a fair hull. My hull bottom has mostly flat surfaces and here a table of offsets was quick and simple.

This particular software is easy to use (by CAD standards) and can fair a line very well. Since gracefully curved lines were important to me, this software was spot on.   With a little playing around ( about a year) I was able to design the hull I wanted complete with the gunnels and combing included the table of offsets.

Since this boat does not have a liner, I was concerned about the hull to deck joint as well as making a separate cap to fit. I decided to make the "cap" integral with the hull, so when I put the foam on my mold it included the gunnels and combing. Also I wanted to do the glassing of this joint while the hull was upside down and still on the mold.



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Last modified: November 09, 2015