ENGINEERING HELP REQUESTED!
I need to narrow down the search for this cannon's story somehow, and if I could determine what country it was designed or made in, that would help a lot. For instance, maybe someone can tell what the country of origin of the "walnut" looking wood the carriage is made of.
However perhaps the most straightforward thing to do would be a dimensional analysis, IF we assume it is a scale model made to some commonly-used scale factor for model cannons, such as 1/6, 1/8, or 1/10. I'm sure others were used but that's primarily what I've seen in 19th C. US-made cannon models, which were made by the government or made for consideration of the government.
The bore is the single most important dimension, and that is 0.610 inches. Both trunnions measure the same diameter so I suspect that's a pretty good number. I tried various scale factors with the known bore diameters for naval guns and the only thing I came close with was a 6-pounder, not really a good naval bore diameter, but that's all that came close. 0.610 x 6 = 3.66 in., close enough to a 6 pdr. bore of 3.67 in.
I wasn't happy to stop there, I don't think it is supposed to represent a 6-pounder naval gun, but something more in the main battery, let's say something like a 24, 32, or 42 pounder, but the numbers don't work out. So maybe it is from a country that had a metric standard? Or if French, we have to use different bore diameters altogether since their pound weights were about 1.1 English pounds in the early 19th C. when I think this model was made. I can't just throw out the possibility that this was a model for a 6-pounder, though, reason being that if this was a private inventor using his own funds, a 6-pounder may have been the largest demonstration gun he could afford, and this model was scaled to represent the largest gun he intended to build, or have someone build, in the future for firing demonstration.
Another dimension one could use for scale is the nominal barrel length, which is Exactly 12.0 inches, from muzzle face to rear of the basering. For example, a USN 32 pounder chambered cannon of 42 hundredweight had a nominal length of 96 inches, so a 12-inch model would be correct for 1/8 scale.
I tried measuring the pitch of the breech closure screw threads, which is 5 threads per 0.28 inches. That seems to work out to 17.857 TPI, quite an odd number, but a fairly tiny error in my measurement could have occurred, and it is really 18 TPI. It didn't seem to convert well to metric, if I did it correctly. I think I heard somewhere that in the UK there were a few different thread pitch measurement standards in use.
One big clue we do have is the tall dispart sight on the muzzle. When I try and place that in terms of national origin, England comes to mind and not too many other countries. The US really didn't put those dispart sights on naval cannons, as far as I know.
Anyone have any ideas please?
