Thanks Andy, Gary and Allen, we will try to get this Nano cannon finished up in a few weeks, but we are still waiting on carriage drawings. We will continue a steadily as we possibly can. Allen, you are not Bad, but you already knew that, right? However we like DD's term best and will call it a NTMTD from now on. Dan, believe it or not, Mike and I know how to create an octagon cannon tube on a manual lathe without special fixtures, cams or milling machines coming into the process. Not our idea, but we saw an instructor at our Gunsmith School do just that 30 years ago! He even let me do a little work on that barrel, so I remember exactly how to do it.
Gary might know too, but as I recall he was always hunched over his bench concentrating intently on the task at hand. The fact that he sat at the bench which had the 12 GA Shotgun pattern in the 48" light reflector right over his head might have had an effect on his studious attitude!!
No, he didn't do it!
Nano update Pictures follow,
Tracy and Mike
I thought and thought about how to make that raised, reduced-diameter muzzle ring and finally decided to tickle it with a small fine, diamond file held
Rigidly. Next two photos.
Holding that file TIGHT!!
Before I hacksaw the piece forward of the muzzle, a little polishing is in order. Small, fine tooth files gets you approx. 180 grit surfaces. So I went straight to 240 grit wet& dry paper next, then 320 grit W&D. You can go to 400 grit on these little guns, but I don't like them quite that shiny.
Getting the .319" diameter surface between the Chase Ring and the Muzzle Swell was tricky to do without rounding off the carefully filed edges, but you can do it. Find a thin piece of wood or metal as I did and fold the sand paper TIGHTLY around it's edge and STAY AWAY from the edges of those two features. Polish in between them only.
I was going to work on the cascabel first, but it's easier to do the muzzle first so you can hold the tube in your vise while drilling the bore.
After cutting off the tail stock centering piece with a hacksaw, file the muzzle flush with coarse, then file cut files while the work rotates.
Next, while holding the tube in a vise or clamped to a bench, carefully mark a center point as before, center punch, file lightly, center drill and drill the bore .188 diameter to 1.812" deep, using a friend or family member to keep your hand drill bit co-axial to the tube axis.
Then chamfer lightly,.010" to .015" at 45 degrees with an edge-chamfer tool in the hand drill. Barely touch it momentarily with light pressure. That's it. Cascabel shaping next.