Frame construction

[jbeyl]

Hello. I have been looking at the various logs for the TFFM swan ships with an eye towards building. I have been curious for quite some time on the complexity of the wooden sailing ship. My question is how do you determine the dimensions for the framing scarph joints and chocks? I do not have books from Goodwin or Steele in my library yet and have not found much through Google. Thank you.

 

Jon

[jbshan]

Your question requires a book or two to answer.  It's not something that can be answered in a couple of minutes on a Q & A forum.  It looks as if you already have some titles in mind, TFFM and Goodwin are modern, but securely based on period sources.  Steele can be a bit obscure as it is a period text.

[hamilton]

Hi Jon

 

I invested in the first volume of TFFM and it describes what you're talking about in great detail (with illustrations and photos to help with visualisation). I have not built a fully framed model, but I can see how this and the other TFFM books would be invaluable in this process, especially for those cutting their teeth on this approach. I will likely buy volume 2 this Christmas and use both for general tips in the construction and outfitting of my Echo cross-section (once I build up the guts to tuck into that project....)

hamilton

[druxey]

Every scratch-built framed model is frightening when you look at the huge overall project. Just focus on one piece at a time in bite-sizes and, after a while, you will have eaten the whole elephant.

[Mark P]

Hi Jon;

 

The TFFM books are a very good source of detailed descriptions of building techniques,  and give information which is clearly explained and illustrated.  This is valuable,  because contemporary sources contain few illustrations,  and are generally written in a hard-to-understand-now fashion.  I would certainly recommend obtaining what you can of these,  depending upon the type of vessel you are interested in. 

 

Another source of information,  again depending upon the type of vessel,  is the number of original contracts which survive for vessels built for the Royal Navy by merchant shipbuilders.  These exist from the later 17th century onwards,  and can be obtained from the NMM. Detailed information concerning the size of scarph joints,  and all scantlings,  is normally contained within these.

 

The down-side of these is the sometimes difficult to interpret phrasing,  and the lack of illustrations.

 

All the best,

 

Mark P

Edited September 15, 2016 by Mark P

[jbshan]

Yes, Mark.  While we have period contracts specifying every aspect of a particular ship, and authors speaking in as much detail in a general fashion, it is extremely difficult to resolve that period information into an actual hull.  There is currently on this forum an attempt to put the data together into a CAD format, and the individual is constantly bumping up against discrepancies and obscurities in the 'instructions'.  That is why I usually recommend using one or more of the modern authors who has already done the winnowing into an understandable form.  The best of those rely on the period information available, in fact are experts not only in building models but also in interpreting the archaic wording, spelling and phrasing of the day.

[tlevine]

The beauty of a Google search is that it is free.  And sometimes it even provides you with answers from individuals qualified to have an opinion.  If you are interested in building a fully framed model, I would recommend developing your library first.  Get the first two volumes of TFFM.  Get Ed Tosti's volumes on Naiad.  Look at prints from the Royal Museum Greenwich which illustrate frame construction throughout the years.  

 

Only then should you decide whether you are as crazy as the rest of us Swan-class builders. If the answer is yes then welcome aboard.

[jbeyl]

Thank you for your responses everyone. I will look into building my library. I am not daunted by the task as I find it very interesting.. My Christmas list will be long on books this year! Thanks

 

Jon

[jbshan]

I should've added that the contracts are often handwritten and the cursive of the day turns the whole search into virtually a palimpsest of information.

[Jaager]

I have the impression that scarphed frames are mainly an English technique.

On a theoretical view, using it may allow for a reduced moulded dimension of

timbering material over butt joins,  If there are more workmen than thick timber,

I can sort of see the point, but I would just make the rider strakes thick instead.

 

If the seam and join surfaces of the scarph joint were not treated properly , would

this not be a locus of a fungal attack and rot?  I suspect that butt joins had an air

gap to resist this.  Could tight - near invisible butt joins be a ship model trait?

 

I have a question about scarph joins:  what was done with timbers where there is  a

significant bevel on  an individual timber?

Edited September 19, 2016 by Jaager

[druxey]

Jaager: if the frame is bevelled, then the scarph (or chock) would also be bevelled to the same angle, otherwise strength would be compromised.

[Jaager]

I know it had to be that way - up to a point - but I wonder if there was a switch to butt joins where the bevel becomes significant.  It would add to the pressure to use cant frames - as much of a problem as they must have been at the deadwood to shape and as weak as they were there.