Question on scarf joints and keels

P

Porpita Studios

Joined
May 28, 2020
Messages
46
Points
78

Hi,
I am in the process of planning a part scratchbuild part kit of the Armata Lancia 1803 1:16 scale model. I am looking for information on keel joints on a ship of this size. Its about 10m in length - so would the keel have scarf joints along it and if so how many? From what I have read so far on boats and wood yards is that wood varies from 6m to 9m lengths depending what was available... so is it just a matter of 'we could only get 6m lengths for the keel so we made a single scarf joint on a 10m length' or is there a specific method or equation to it? And are they positioned in specific places? (Thnx in advance for any help!)
 
The true keel of a boat 10m long, may not be a full 10m, you have stem up front often added before start of keel and the stern timbers, often vertical added to back of keel, which depending on plans and how designed the true keel would be 8-9m
 
Kkonrath said:
The true keel of a boat 10m long, may not be a full 10m, you have stem up front often added before start of keel and the stern timbers, often vertical added to back of keel, which depending on plans and how designed the true keel would be 8-9m
Click to expand...
Yes noted - I just was trying to understand basic configuration - that said I think I may have found a suitable answer (which ties in with your comment) with a ship a similar size the S. Caterina which has a scarf joint at bow and stern to accommodate the stern and bow timbers - so that would reduce the keel size down anyway to 'x' within timber sizes available at the time meaning there would be no need for any further scarf joints along the keel. (Hope that makes sense!)
 
@Porpita Studios,
I have read that a scarph joint was not desirable at the center of the keel length, due to the pressure/strain exerted here, but the scarphs would be placed at regular intervals. That said, I think that in addition to the joints at the stem and sternpost, you would want to have two vertical scarphs along the keel length to maximize their distance from the center. This would divide that length into three roughly equal beams, which should work out to be within the 9m max. length for keel beams that you mention.
Length of the keel scarphs themselves are given to be 1/5 to 1/6 of the length of the individual keel piece to ensure sufficient overlap (Goodwin, Construction and Fitting of the English Man of War, 1650-1850).
This is coming from a noob, so I'm sure other folks can add something to this, but I hope that is helpful.
 
Last edited:
Brewbrarian said:
@Porpita Studios,
I have read that a scarph joint was not desirable at the center of the keel length, due to the pressure/strain exerted here, but the scarphs would be placed at regular intervals. That said, I think that in addition to the joints at the stem and sternpost, you would want to have two vertical scarphs along the keel length to maximize their distance from the center. This would divide that length into three roughly equal beams, which should work out to be within the 9m max. length for keel beams that you mention.
Length of the keel scarphs themselves are given to be 1/5 to 1/6 of the length of the individual keel piece to ensure sufficient overlap (Goodwin, Construction and Fitting of the English Man of War, 1650-1850).
This is coming from a noob, so I'm sure other folks can add something to this, but I hope that is helpful.
Click to expand...
Thnx, on this ship the keel length is max 10m that includes bow and stern so likely only vertical scarf joints at bow and stern based on all of the above comments. Thnx for the input very much appreciated!
 
Porpita Studios said:
Hi,
I am in the process of planning a part scratchbuild part kit of the Armata Lancia 1803 1:16 scale model. I am looking for information on keel joints on a ship of this size. Its about 10m in length - so would the keel have scarf joints along it and if so how many? From what I have read so far on boats and wood yards is that wood varies from 6m to 9m lengths depending what was available... so is it just a matter of 'we could only get 6m lengths for the keel so we made a single scarf joint on a 10m length' or is there a specific method or equation to it? And are they positioned in specific places? (Thnx in advance for any help!)
Click to expand...
Hallo @Porpita Studios ,
we wish you all the BEST and a HAPPY BIRTHDAY
Birthday-Cake
 
As I continue to plan for my Stick Build I am also interested in the Scarf Joints, But as it would pertain to Ribs, and Stems (I'm guessing Vertical).
H.W. Curtis has been teaching me "The Elements Of Wood Ship Construction (1919)" <--Click here.
He goes into great detail about the Scarf Joints, and where they are placed with the bolts.
(See Pic Below)
My (2) Questions are...
(1) Were the bolts of the 1800ish ships threaded metals. or was that kind of a Pin with a Wedge hammered into each one.
(2) H.W. doesn't go into detail about fashioning of the Ribs. Would those have the same kind of Scarf Joints (Plain, Hooked, Key Locked, and Key Locked Hook), or were they really "Carved".
(2.b) It makes sense that the Ribs would be Rabbet'ed into the Keel, or were they "Carved/Jointed" into the true "V" that Modelers use?
1625386928996.png
 
You must log in or register to reply here.
Back
Top