Wooden Boat People

By McKenzieDriftBoat.com

Lofting side and bottom panels

I've read Roger's book in addition to both books from Greg Rossel as well as Dynamite Payson and Sam Devlin. All excellent stuff and I've learned a wealth of knowledge, frankly too much as it's taken me a while to digest it and get off center.

One thing I can't figure out - the critical cuts, at least to actually start building the boat, are the side panel or extended panel plans. The ones that actually show the exact dimensions for any dish in the chine or sheer. It's not such a big deal to extrapolate those from the standard 3 views common to most plans (profile, body, & halfbreadth) if you're building a constant rocker dory arising from a perfectly straight bottom edge of a side panel.

But if the plans don't come with an expanded panel view, how do you determine the measurements of the dish in either the chine or sheer (guessing you only need one if you know the width of the panel at that point) at any station?

Another way to look at this is how do the guys that measure existing boats and retro-draw plans figure out this same info?

Thanks for any help and thanks for a great resource. I've enjoyed back reading many of the pages.

- Jon

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Replies to This Discussion

Permalink Reply by tungsten on September 16, 2015 at 6:41am

I think a lot of it is trial an error,after building a few boats and 10 or so models you get a grip on what makes what.Bottom shape and side flare controls the rocker,dishing of the shear you don't normally see as the oar locks need to be the highest point.You do see a little for and aft of the oarlocks to make it easier to get in the boat.This creates trouble when trying to attach gunnel's.

Traditionally framed boats have sides that come from 4'x16' panels,you measure up 28" on one end 20" on the other draw a line and bobs your uncle.26" 22" is also common.

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Permalink Reply by tungsten on September 16, 2015 at 7:01am

I was timed out for an edit,also its that tear drop shape of the bottom that gives the boat that traditional look.

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Permalink Reply by J. Snider on September 16, 2015 at 7:08am

Forgot to mention. I'm starting some type of Briggs boat, maybe with a wider bottom. Thx.

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Permalink Reply by Roger Fletcher on September 17, 2015 at 7:11am

Over the years I have recovered the lines of 13 different dories and the biggest (and most entertaining) challenge has been to define the bilge, or side panel layouts. What you see in the profile is always diifferent from the full panel layout. My dear friend, Dynamite Payson put me on to a technique that if done accurately is sure-fire on target. You can uncover his process by studying Dynamite's techniques for crafting his model “plugs” in his Dory Model Book (1997, Woodenboat Books ). Using scaled profile and breadth lines one can hand-craft a 3-dimensional scaled “plug.” Dynamite's purpose was to create the form for his lovely moldels. My purpose was to craft the plug so as to mark and “lift” the side panels off the “plug.” Once the “plug” was completed I used vellum and a light glue spray to lay the vellum around the form, trace the outline, carefully mark the staion lines and then lift the result from the plug. There sits your side panel.

There are CADs that will do the same thing, but even the popular designer Phil Bolger didn't trust the emerging programs of the day, and he contracted with Dynamite to pull his bilge from Dynamite's “plug” crafted to Bilger's lines. This is one reason Dynamite became the primary source for several of Bilger's small boats.