johnsmachines

My plan to make a model of this 1861/1875 American naval gun had not progressed for 2 months.

I have excellent plans of the barrel, but only tourist photos of the carriage and sloped slide/traversing platform. None of the hundreds of photos on Pinterest, Google Images, Wikipedia, Google Search etc were of the underside, where there had to be mechanical components, which would be vital for a model.

Enquiries to the museum (Patriot’s Point Naval and Maritime Museum), and a succession of official US records departments, museums, naval institutions etc etc had produced only courteous replies, but no drawings or other records relating to this carriage or platform.

Originally the Dahlgren barrel was mounted on a wooden carriage and platform, and I did find some good, original drawings of those. And even an stl file on “Thingiverse” which I 3D printed in PLA.

With my failure to obtain decent information about the iron carriage and platform and I was at the point of either abandoning the whole project, or going to South Carolina and personally measuring up an original, or making my model with a wooden carriage and platform and steel barrel of course, using the stl plans from Thingiverse. Unfortunately, going to South Carolina personally is not an option.

Then I had a brainwave.

I posted a plea for help, on the “Ships of Scale” website. Asking for someone, anyone, who lived near the Patriot’s Point Museum, to go to the museum and take some particular photographs and measurements of the original gun.

Lots of views of the plea, and quite a few responses with advice, but no offers to actually take the required photos and measurements.

Then, after 2-3 weeks, a gentleman from Aiken, South Carolina, said that he was prepared to make the 140 mile journey from his home to get the information for me. His name was Jonathan Gerson (mentioned here with permission), and coincidentally he is also building a model of USS Constitution.

BUT, the guns were not at Patriot’s Point Museum. When Jon arrived there, he could see only concrete pads where the guns had been. An enquiry revealed that they had been moved to a soccer stadium a few miles away (why!??). No mention of that change on the museum website, or in several emails from museum staff to me.

So off Jon went to the stadium, where he had some fun photographing and measuring the guns, and even more fun noticing the lady joggers in the vicinity.

In due course I received 45 photographs and some dimensions of the Dahlgren, which were just what I needed. They revealed the undersides and suspected but otherwise unproven evidence of gears and brakes.

I offered to defray Jon’s expenses, but that was flatly denied because he was “pleased to help a fellow model shipbuilder”. Needless to say, I remain flabbergasted and awed at his generosity. I sent the printed model pictured above as a gift, and received a very nice thankyou in return.

So, I am now able to continue machining the barrel. I have drilled the bore to 16mm, and must enlarge that to 20mm, and then do the rifling while the steel blank is still a cylinder and easily able to be held. (well, fairly easily). I also need to make a thread at the breech to attach the cascable button. And to drill holes for the trunnions. Then the external “soda bottle” shape of the exterior can be turned. None of that could be machined until I knew whether I was making an 11″ smoothbore or a smoothbore converted to an 8″ rifled cannon.

Needless to say, this will be a model, and will not be capable of being fired, for legal reasons. But it will otherwise be as accurate to the original as I can make it.

Now, back to rigging the Constitution.