Preview: How to Loft a Boat, Part 2 — The Lofting Sequence
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December 2, 2021
Email this Video to a FriendSean Koomen, Chief Instructor at the Northwest School of Wooden Boatbuilding (NWSWB), goes over the school’s lofting sequence.
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13 Responses So Far to “How to Loft a Boat, Part 2 — The Lofting Sequence”
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Mike Justice says:
The most comprehensive material explained in an elementary way.
Even a 6 year old understands this.
I have wasted hundreds of dollars on lofting boat books, and watched useless videos that have tried to explain what this instructor has explained in the most simple way.
Some have a gift for teaching and the others need to stay seated.
John Homer says:
Are you going to explain how to take lines to paper fro an actual boat?
Steve Stone says:
Apologies Jim, we’ve included a note above that this is the most recent part and the next video is in the editing queue. We’ll be releasing the series over the winter and spring.
Drew Britten says:
Why are diagonals important in lofting? Isn’t the shape of the hull completely defined by the other 3 views?
Bill Theurkauf says:
In areas of the hull with lots of shape, in the plan view, there can be fair amount of distance between the points defined by the intersection of the buttock and waterlines and the hull. The diagonals fill in the gaps and help get an accurate shape for the molds in these areas. I’m no pro and have only lofted a couple of small boats, so there may be more to it.
Donald Ziolkowski says:
The other important thing to remember is this: If you look at the intersection of the body plan and the buttock lines, you will notice in many cases they meet at a very obtuse angle. This means that it’s really difficult to discern that intersection “point”. What a diagonal will do, however, is meet the body plan at what is very close to a right angle. This makes it a great way to ensure you’ve plotted the point correctly and that things are fair. I’ve actually seen some Tables of Offsets that are completely based on the diagonals, because they very precisely define points.
Sean Koomen says:
Great question Drew! You’re correct in saying the hull is sufficiently represented by the profile, body and plan views. The diagonals are a powerful tool for fairing the hull, as they offer stronger intersection points with the lines in the body plan. Diagonals don’t have much use in constructing the actual boat-but are essential for fairing up the lines.
Richard Raymond says:
So, you use the table of offsets to do the lofting so you can make patterns to build the boat. Where did the table of offsets come from?
Milo Feinberg says:
They are provided by the designer. The designer gets them by measuring off of the scaled lines drawing.
Donald Sullivan says:
So many of us associated with OCH have built small boats with kits from Hewes and Co or others, but this is the holy grail we all knew we were missing; I can’t say I wish I had lofted my Caledonia Yawl from scratch, but it is sure great learning about it now. Thank you for this articulate presentation.
Gene Nelson says:
Great way to spend a cold winters. day. !
John Homer says:
Great class. Thank you for taking the time and explaining this…very helpful.
William McCaffrey says:
Great presentation / class looking forward to the rest. I lofted my first boat about 20 years ago and had to learn all of this from several boat building books. It’s great to see a class being put together for the cyber students.