Blaster Bob, We are really glad to hear you are feeling better. Mike and I certainly wish the very best for Lance and anyone else who may be battling cancer.
Double D. wrote:
I will be nearby these Cannons in April...it would make a nice day trip.
Tell me what measurements are required.....
Double D., As for the dimensions that should be checked to make a positive I.D. on any cannon, we have listed a bunch that will make a positive I.D. possible. You could get by with less, but you should never approach this task as a lark or casual experience. By being serious, you will save time and have dimensions you can believe in.
With a flexible, flat steel tape you should measure the bore dia. by placing the tape in the bore, two inches back from the muzzle, in a single coil, trying to keep the coil in a plane which is perpendicular to the bore axis. With the entire circle of tape pressed against the bore, ignor the end of the tape and read across the two inch mark to see what number aligns with that mark. Jot that reading into a small notebook you bought for this purpose and then subtract two inches. THAT is the bore dia. Measure the largest dia. of the muzzle swell, the diameters at which the chase taper is smallest and largest, the smallest and largest diameters of the second reinforce, the dia. of the first reinforce and the dia. of the breech ring. The rimbase dia and the trunnion dia. are two to add.
With a conventional, concave, steel tape measure the tube length. This includes only the distance from the muzzle face to the back edge of the breech ring. OAL is nice if you can manage the cascable length which is a bear. The other linear dimensions you need are the distance from the axis of the trunnions to the back edge of breech ring and the rimbase face to rimbase face dim. and the length of the trunnions.
Photos are easier and should include a muzzle face shot which is square to the bore axis, a top view which details the muzzle mouldings and astragal/fillets of the chase. A top view of the trunnion area, square to the trunnion axis and as parallel to the top of the tube’s second reinforce as you can manage. A top view of the cascable and breech ring area including the vent is essential. A side view of these last two areas is essential as well. A rear view is good to have, especially if any markings are present. Separate views of each marking or cluster of markings is very, very important. Look under the tube if possible, especially in the breech area for small markings. An over-all side view is good to have too. A quarter should appear in all photos, square to the lens axis. A small dab of modeling clay will stick the coin temporarily to almost any location on the cannon. It is used for dimensional scale, of course.
A copy of an original drawing for comparison is also needed. We have very few drawings of field artillery tubes. Maybe someone else has one of the 1836, iron, field artillery tube.
Tracy and Mike