# Flat plate bending in two planes

Discussion in 'Boat Design' started by Annode, Apr 26, 2020.

1. ### AnnodePrevious Member

Well I agree. Its how we get from the sheer to the chine thats the subject of this exploration into two dimensional bending. A flat surface plunging verticall down through the waterline on a boat this size is not optimal. Angling the side helps. Adding a slight curvature turns it into an artform, not something that came from a boilermakers basement. How many falt surfaces are there on Camper Nicholson boats? Why?

Anyway, this thread isnt a debate about aesthetics, its a discussion about forming 6mm plate into slguth compound curves. I used 2.5m square plate for the calculations, but the numbers are not much different for 6x3m. I am hoping to hear from a boat builder that has actually done this.

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### gonzoSenior Member

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### clmangesSenior Member

Oh, please. Just one possible example out of a great many, but is this ugly?

Skerry: 15-foot Double-Ender - Fast Rowing and Sailing Dinghy https://www.clcboats.com/shop/boats/wooden-sailboat-kits/skerry-rowing-sailing-dinghy-kit.html

Do note that this boat is composed entirely of flat stock; all developable surfaces.

I understand that you're thinking of something a lot different, but you can't condemn 'flat plates' on aesthetic grounds. I'm sure you have other grounds for rejecting the technique; well enough.

By the way, those graceful profiles in the columns of the Parthenon--those could be developed out of flat plates in at least three ways I can think of without even trying.

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### Mr EfficiencySenior Member

You are the one who has made it about aesthetics, it is entirely possible to make a developable surface that has no flat surfaces anywhere, but try and force materials to take up compound curved shapes without expensive equipment and/or well practiced hands, and you will be vocalizing the "tinkers curse" x 100.

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5. ### AnnodePrevious Member

yet you fail to articulate a single one...

yet you fail to articulate a single one...

>Mild steel can be bend into all kinds of shapes. Methods like....

I think you missed the part about WITHOUT FORMING think origami with structure

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### bajansailorMarine Surveyor

How is the design of your fine vessel coming along Annode?
We haven't seen you on here for a while; I was wondering what had happened to you.
Can you give us a re-cap on here (or one of the other threads that you started on the design / construction issue) to bring us up to speed please?

Last edited: May 25, 2020
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### clmangesSenior Member

Didn't think it was necessary; didn't want to encourage topic drift.

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### CDBarrySenior Member

Get publication a443648 from DTIC, the 1982 NSRP report on line heating by the late Lou Chirillo

I put an article up here as well at one point.

9. ### AnnodePrevious Member

>Get publication a443648 from DTIC, the 1982 NSRP report on line heating by the late Lou Chirillo

What from where?
Thank you for the suggestion tho ). Yes it looks like heat is the going to be the battlefield weapon of choice for metal torturing

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### bajansailorMarine Surveyor

Annode, why make life difficult for yourself?
Instead of torturing your steel on the battlefield with significant amounts of heat, why not design the vessel so that all the plates are developable and easily curved?
We built an ally boat here 20 years ago which needed some considerable heat torture to get the bottom plating to wrap around to the stem - it was not much fun, it didn't look good, and the boat did not thank us for this design fault.
On the topic of design, how is the design of your boat coming along?

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### CDBarrySenior Member

Defense Technical Information Center, report a443648 by Chirillo.

However, just Google Chirillo a443648 "line heating". Lou had a website with his NSRP reports on it as well as a lot of other stuff. I don't know if it is still up.

============

It's still up. This is the specific line heating manual, but look at the whole website.

Line Heating – November 1982 http://lou.chirillo.com/referenced-books/national-shipbuilding-research-program/line-heating-november-1982/

CDR Chirillo was a remarkable man and made important contributions to modern ship building. I was privileged to have known him.

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