Summary for black powder cannon finish Discussion
Black powder cannon builders asked two related questions: how to get a durable black exterior finish, and whether the internal bore must be perfectly smooth. For the outside, Tom Walen said black oxide would be the best finish for the application, but advised having a reputable job shop do it because of safety and environmental issues. On the bore question, James Watts, Dave Fitz, and Mark Jackson all said the grooves from boring are not likely to endanger the cannon, especially for salutes or very light projectiles. If a smoother bore is desired, Watts suggested a flap wheel or, better, a hone; Fitz specifically recommended a brake cylinder hone, and Jackson mentioned reaming or honing. Erik Johansen and Guy Perram emphasized that a smooth bore is safer and easier to clean, with Perram warning that real cannons are not toys and that loading and firing should never be rushed.
I build small black powder cannon as a hobby. I am currently bead blasting and painting the steel parts. This has mixed results when firing. The paint sometimes gets scratched in handling or recoil. I want a more durable black finish that looks authentic(not too shiny) and that I apply myself.
Thanks for your help!
Joel White
– Goldsboro, North Carolina USA
2000
Black Oxide is the finish that would be best for your application. The down side would be that you should have a reputable job shop perform the service and not attempt it yourself due to safety and environmental issues.
Regards
Tom Walen
Springfield, Massachusetts
2000
Probably true, Tom. But it does strike me as rather ironic that it’s considered okay today to build and fire cannons … but dangerous to apply the black finish 🙂
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
? What metal are you using?
Cast or machined?
Generic or true replica cannon?
What size?
Any good web sites for getting dimensional plans for say a 24 pounder?
James Watts
– Navarre, Florida
2000
Multiple threads merged: please forgive chronology errors and repetition 🙂
Black powder cannon internal bore
Q. I am writing to ask about the black powder cannons. Is it essential for the inner bore to be completely smooth?
James Munday
– Hobart, Tasmania, Australia
2001
A. No, if you are not firing any objects out of the cannon the bore does not have to be smooth,
if you are how ever firing something out of it, it should be smooth enough that the projectile does not catch in any spot of the bore
Erik Johansen
– Danvers, Massachusetts U.S.A.
2003
A. A smooth bore is a happy bore. Not to be Boring, but; a smooth bore is safer because it allows you to completely lubricate and it ensures all burning embers are extinguished. Safe shooting. Peace. S.B.
James Scott Brown
M.R.U. – ElDorado, Arkansas, U.S.A.
2004
Having done Revolutionary War Re-enacting with a full size 6 pound cannon the best way to go is with a smooth bore. It will allow you to extinguish any and all material still alive in the bore after you fire the cannon. Also, wrap your powder charge in an aluminum foil sabot, there is nothing to burn afterward and it is easily removed with a worm. Always do a double tube sponge and cleaning. Never, ever, rush. A pre-mature firing will hurt the rammer, badly. If the rammer is lucky he would only lose half his hand, unlucky, his arm. Real cannons are not a toy.
Guy Perram
– Medina, Ohio, USA
2006
Multiple threads merged: please forgive chronology errors and repetition 🙂
Q. Hi,
I am currently constructing a black powder cannon and have managed to get everything perfect except for the internal bore. Due to the vibrations involved when using a boring bar on a metal lathe there are little grooves all along the internal bore. Is it important to have a perfectly smooth bore, due to the grooves is it likely to explode? The cannon is made of 64 mm diameter mild steel and the bore is 1 inch in diameter, it would be greatly appreciated if any one could give me any relative information on this subject or could tell me a method of smoothing internal bores, not to difficult though.
Thank you,
James Munday
– Tasmania, Hobart, Australia
2001
A. You can smooth the bore with a flap wheel sander or slower, but better, use a hone. Get about three different grades of abrasive sizes or it will be terribly slow. Option is to start with the coarsest one you can find. If the finish is fine after that, quit. If not, go to a finer stone.
James Watts
– Navarre, Florida
2001
A. The grooves won’t endanger anything.
If you still want the interior perfectly smooth, go to an auto parts store and ask for a brake cylinder hone. The gadget will usually have 3 or 4 spring-loaded arms with a polishing stone at the ends. Run this up and down your bore with an electric drill a few times to take the grooves out.
64 mm OD and 1 inch ID is safe enough for salutes and very light projectiles like wood targeting balls. Anything heavier, consult a serious black powder outfit. Pyrodex in particular can tell you all about safe pressures.
Dave Fitz
– Ogallala, Nebraska, USA
2001
A. Cannon builder: don’t think the grooves will hurt a thing, but if you want a smooth bore then you might want to use a 1 inch or a 1-1/16th ream. A hone will also do the job as the other two responses noted. Got any pics of that jewel?
Mark Jackson
– Charleston, West Virginia
2004
2006
Q. HOW LARGE AN OPENING SHOULD BE PUNCHED INTO THE CHARGE BY THE PRIMING WIRE?
CHUCK WALDRON
Valhalla’s Pirates – Pt Pleasant, New Jersey