Skidmark wrote: "I'm thinking they have a rivet head not shown in between the 2 plates and what you see on the exposed surface is the side of a rivet that was beat down in a countersunk hole to give a flush appearance."
We were writing about the possibility of peg rivets being used prior to this thought by Mark, so I am trying to envision what hardware configuration he describes, the composition of which is baffling to me. The part which is most troublesome is this, "a rivet head not shown in between the 2 plates". In trying to think of a good analogy, a vision of one of those politically wrought, "bridges to nowhere", in Louisiana comes to mind, in that the thing has one half missing and serves no useful purpose. From Mark's description I am seeing a round rivet head on the inside of the 3.25" wide iron periphery strip, "between the two plates" (cheek plates) and a flush rivet on the other side of the same iron strip. This must be wrong, because it joins nothing together. Perhaps you could provide a sketch, Mark, to help us better understand this configuration? Our purpose here is NOT to put Mark on the spot, but simply to bring some clarity to the subject. We support his field research on these big mortar beds by doing, not just by blabbing.
”Not pop rivets! Peg rivets!
The theory is there is a rod or bar between the two plates that extends from say top to bottom. A piece of flat trim with a tapered or counter sunk hole covers edge of the plate and the cross rod/bar end sticks through the hole in the trim. The peg is driven in flaring the end which sucks the trim down tight against the edges of the two plates.
Its one of those things you notice when looking for something. It looks interesting but has no relevance to your current topic, then later, something comes up like this topic it and you go- "hey I saw that some where.
Do the location of the rivets have any thing to do this the orientation of the bolt holes? Such as the blots passing through a flat bar and the end of the bar is the rivet.
I would love to see an x-ray of one of these cheeks. It would give some wonderful insight on how these cheeks are constructed.”
The "Pop Rivet" comment was merely to get your attention, Double D., because we wanted to hear more of your analytical thoughts on this subject. Your second comment in red above is proof that you hardly ever disappoint us. From our observations, the riveted end of the pins or rods are in between the bolt locations, even if you project the rod at any reasonable angle from the 3.25” wide edge strip, into the space between the cheek plates. Another reason for an arrangement such as you described,
"the end of the bar is the rivet." being remote, is the extra lathe operation and cost which would be required to create this special hardware. In addition, the riveted rods only account for a third the total number of cheek plate cross bolts.
As far as the X-Ray goes, if you come across any soldier of fortune who is making an obscene amount of money in your travels, just convince him to send me a bundle so I can rent one of those portable machines on a trailer. I have a heavy-duty socket hitch and trailer brake set-up on the Suburban, you know.
If anyone has any new info or thoughts on the big seacoast mortar, please post them. For us, it's time to shift gears and start the second part of the Denver City Park Seacoast Cannon series. Everywhere Mike and I see the huge, XI Inch Dahlgren Shell Gun, we have to marvel at them for their excellent design, extreme endurance and hugeness. This is one "bad-ass" naval cannon! Aboard the Federal ship Kearsarge, one of these big Dahlgrens, mounted as a pivot gun, sent Captain Semmes' extraordinarily successful commerce raider, CSS Alabama to the ocean floor in '64.
Captain Porter in '61, even before the aborted attempt to reinforce Fort Sumter in Charleston Harbor, agreed to take the Powhatan armed with a 10 gun broadside of IX Inch Dahlgrens and an XI Inch Dahlgren Bow Pivot Gun, and a Collins Steamer loaded with Army troops, to relieve Lt. Slemmer's tiny garrison at Fort Pickens at the entrance to the Confederate held Pensacola Bay with all the forts on the north shore and the Navy Yard.
This was a super secret mission initiated by the Secretary Of State and agreed to by President Lincoln. Not even the Secretary of the Navy, Welles knew about it. Very early in the War in '61, with southern naval officers resigning their commissions left and right, it was almost impossible to get any mission directive thru regular Navy channels without the Rebels knowing about it immediately. What happened to the two ship flotilla when they arrived off fort Pickens? From Admiral Porter's Memoirs, we have the answer in his own words published in the book,
Blue and Gray at Sea by Brian Thomsen.
"General Bragg had a large force of troops in and around the navy-yard, and the second day after our arrival a number of tugs and schooners, filled with soldiers came down from Pensacola and approached Fort Pickens, whether with the intention of attaching it or not I don't know. They no doubt took the Powhatan and the Collins steamer for store-ships, and thought it a good time to commence operations and secure "loot," , but I changed the programme by sending an eleven-inch shrapnel among them, which, bursting at the right time, threw up the water in all directions.
The flotilla scampered off in quick time, and left us to quietly prepare the fort for any emergency, and it remained in our possession during the whole of the civil war." There were, of course, many other incidents involving the XI Inch Dahlgren during the war, but these are two that come to mind.
The photos of the City Park Dahlgren will be posted this evening after work,
Tracy and Mike
