Ways to bore a cannon barrel

Sweet! Great work.
Robert
 
OK Gents. I am at a crossroad now - not sure which way to go again. I now have the entire bore drilled out to 1.125" to a depth of 16". Of course the finish leaves a lot to be desired, not to mention I'd like to clean it up and enlarge it to 1.200 / 1.250 inches. If I go with a boring bar, what is the maximum shaft size I could use? I'm thinking 1" is too large and won't allow chips to move freely. .750 inch seems like it would be a little flexible at 16" length, and might not achieve the desired consistency for diameter. Any ideas or other options open to me that won't cost an arm and a leg? Really need some guidance here......:confused:
 
Your not going to get a small boring bar to bore that deep without all sorts of chatter and havic. Even a solid carbide boring bar you going to have similar problems. Your best practical way to finish the bore is to ream it with several sizes of reamers until the size you want is reached.

Now, if you want, you could make a reaming head that has wear pads mounted at 90 and 180 degrees from the cutter and the cutter is set up to skive the surface of the hole. The cutter would have to be retracted many times to remove chips and add cutting oil. Unless you use pressurized coolant as the do on larger deep hold drilling/ reaming machines are set up to do. Ken
 
I would use a MT drill bit just under the final size and long enough.

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Thanks guys -still scratching my head and pondering a solution here.....
 
Expansion reamer sounds like the way to go from this point .
 
Just get a reamer and add an extension like you have I picked up three carbide reamers on eBay right around the size you need if you have enough power might be able to take it straight to finish size but prob not. Get a 1-3/16 sd drill use it in your extension and get a 1 1/4 reamer and be done close enough for a cannon. Also I would feed the reamer with carriage feed and prob rig a hose (maybe 1/4 copper line for stiffness and air if you don't have coolant) pumping some coolant in there to flush chips. I recommend the carriage for feeding the drill too so it's easy to retract and insert.
 
If it is for actual firing often times those have a smaller diameter powder charge area at the bottom. Like a 3/4 inch diameter on that and 1.5 inches deep or so. That way there is more metal where the explosion occurs and your fuse hole is to the back of that cavity.
 
Cadillac STS said:
If it is for actual firing often times those have a smaller diameter powder charge area at the bottom. Like a 3/4 inch diameter on that and 1.5 inches deep or so. That way there is more metal where the explosion occurs and your fuse hole is to the back of that cavity.
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I have heard of that on larger cannons but I feel like this cannon being steel and relatively small bore should be ok. But I think you are right.
 
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