Well, I’m on my way to starting a dangerous obsession. I started my project this week.
I’m using CU Cannons drawing to create my first golf ball mortar. I’m using a hunk of STAINLESS that came out of a pump shaft. Certainly not ideal, but do-able, free, and conscience clear if I screw up the machining. This is more or less practice. See, this isn’t just my first artillery project, it’s my first metal working project period, it’s like I’m feeling around in the dark trying not to stub my toes.
Here are the steps I’ve gone through thus far:
1) Cut stock to length, and faced muzzle end.
2) Bored 1/2” dia. hole full length of bore to powder chamber (5”).
3) Bored 1.5” hole nearly to length of flutes on bit (2.75” deep)
4) Used boring bar to increase bore dia. to ~1.7” (near finish) for the first three inches that were done in step 3. I was told to do this for chip clearance.
5) SLOWLY bored with 1.5” bit to a depth of 3 7/16 (this is the depth at which the ½” radius to the powder chamber begins). I went just far enough to fill the flutes with chips, then would back the bit out and clear the hole.
Next I need to:
6) Use the boring bar to get to near finish bore dia. on the final inch or so of bore.
7) Radius powder chamber and bore bottom.
HELP: I need to know how to go about putting this radius in the powder chamber and bore bottom. Can I grind the harden the radius in a piece of flatbar and use that to cut the radius.
See attached pictures for my progress. I will update as I go. Hopefully I can help someone like myself in the future.