Taking lines and offsets off an existing boat?

[JimW]

Hi, I have been reading and enjoying this list for some time, I have never had anything to contribute, that was not answered better by someone else. Now I have a question. I plan to take the offsets from a sampan to make a model, and perhaps a replica. I remember reading about a method for doing this a long time ago, I think it was by John Gardener, but I'm not sure, it may have been in The National Fisherman, all of my copies of that publication have turned to dust. I will call Mystic on Tuesday, but I thought someone on this list might know where I could find this, or a similar article, on this subject. Thank you. Jim,

[Dave Fleming]

Paul Lipke: Filed Manual for Documentation of Small Craft

John Gardner: The Dory Book

Edson Shock: in Leavens' Catboat Book

Walt Simmons: via his web site

WB #19: Taking Lines

AND:

My absolute choice for all people interested in wooden boats as a primer full of information...
***The Classic Boat*** from Time Life Books circa 1977.
Should not be too hard to get a copy through the many on-line used booksellers.

edited to add:
This is interesting.

Taking Lines From A Hull (http://www.yacht-designer.co.uk/page13.html)

[ 09-05-2004, 02:09 PM: Message edited by: Dave Fleming ]

[Bruce Hooke]

Didn't WoodenBoat publish an article on this a year or two ago?

[Jon Etheredge]

The web site "Taking Lines From A Hull" that Dave referenced mentions the use of a "chain girth device". This is a tool that you can easily make for yourself if you are so inclined. Here is a version that I made when I was in boatbuilding school in Norway:

<CENTER>
http://www.imagestation.com/picture/sraid138/pfb260fd73dd28645078ca6d76ddc3106/f721ef4e.jpg
</CENTER>

This one is made of many pieces of birch measuring approx. 3/16 x 3/4 x 3 1/2" that are riveted together. There is nothing sacred about the dimensions though, the pieces can be any size you like.

In Norway, I used the tool for taking off the inside shape of hulls when fitting sawn frames. In traditional Norwegian construction, the boats are planked lapstrake with the boat right side up with the keel set on blocking. The frames are jogged to fit the laps and are actually cut with a hand axe but they are what we would call sawn frames here in the US. There is no lofting and molds are not used in this style of construction. The frames are fitted after the planking. The chain-like device shown above is used to get the initial, rough shape of the frame and then the fitting continues by scribing for the final fitting.

[ 09-06-2004, 12:34 AM: Message edited by: Jon Etheredge ]

[Roger Stouff]

Originally posted by Jon Etheredge:
The web site "Taking Lines From A Hull" that Dave referenced mentions the use of a "chain girth device". This is a tool that you can easily make for yourself if you are so inclined. Here is a version that I made when I was in boatbuilding school in Norway:

<CENTER>
http://www.imagestation.com/picture/sraid138/pfb260fd73dd28645078ca6d76ddc3106/f721ef4e.jpg
</CENTER>

This one is made of many pieces of birch measuring approx. 3/16 x 3/4 x 3 1/2" that are riveted together. There is nothing sacred about the dimensions though, the pieces can be any size you like.

In Norway, I used the tool for taking off the inside shape of hulls when fitting sawn frames. In traditional Norwegian construction, the boats are planked lapstrake with the boat right side up with the keel set on blocking. The frames are jogged to fit the laps and are actually cut with a hand axe but they are what we would call sawn frames here in the US. There is no lofting and molds are not used in this style of construction. The frames are fitted after the planking. The chain-like device shown above is used to get the initial, rough shape of the frame and then the fitting continues by scribing for the final fitting.Jon, that is MEGA cool! :cool: Thanks for posting it.

RS

[Chadd Hamilton]

Yes, Jon. Thanks for posting that. I've been using one of those flexible ship curves or whatever they are called, but it's a little too short for some applications. I'll have to fabricate a couple of these joggle strips and give one to my son to play with ;)

Chadd

[ 09-07-2004, 02:18 PM: Message edited by: Chadd Hamilton ]