^^ Arlo -- I completely agree with the "metaphor" aspect of this teaser...
...but JBElliot, what's wrong with welding? It's the most effective and modern way we have today of joining two metals together, and I would think it would continue to be in practice (in some form) 240 years from now.
, I would expect that in 240 years there would be so many advances made that welding two pieces of metel together would no longer be the most effective way to produce a larger piece of metal.
As the example I gave, given sufficient energy a transporter could produce pieces of metal (or anything that in its memory) of any size. Given the energy needed to warp space enough for starships to travel at warp eight, it would seem warp engines could easily provide all necessary energy. Furthermore, a single defect free (since the transporter would construct every part of the metal down to the atomic structure) would be stronger and more structurally sound that two pieces of metal welded together.
240 years ago ocean going vessels were made of wood. Today no ocean going vessel (other than pleasurecrafts) are made from wood and few, if any, of the techniques used 240 years ago are in use today. Thus, I would expect that in 240 years few, if any, of our ship building techniques would be in use.