Miniature Cannon build

[rero360]

For a school project, I have been building a miniature cannon. I fully intend on making it fully functional. Its not completely done yet but I thought I'd share some pictures of the progress.

The barrel was made from a 12" long 2.5" diameter piece of 4140 steel, it was sent out to another shop that specializes in deep hole drilling to drill the bore which is .50" in diameter and to a depth of roughly 10.25" I intend to mill out the trunnions from the band of metal you see in the middle and if need be drill and tap them for extensions to bring them to the outer edges of the side plates of the carriage.









The carriage is comprised of a mild steel square stock axle, turned down on the ends to accept the wheels which I purchased and are sand cast aluminum. The side plates are also mild steel and the trail is 6061 aluminum. The trail still has a fair amount of machining to be done to it to shape it. Also will need to drill and tap it for the elevation screw. The top straps to hold the cannon in place on the carriage will be made out of brass.



And for a nice little touch, the wheels are kept on the axle via AR-15 firing pin retaining pins. I will update it as progress is made, and should have videos up of the barrel being turned as well.

[Turo]

Very cool! My dad's working on one that's a .4 scale model of a napoleon cannon IIRC. I've always wanted to do one like yours though.

[OldShooter32]

The "top straps" are really "trunion caps" -- not sure why you left so much metal just behind the trunions, the chase should have a slight taper and the muzzle swell should be gentler... Waiting to see the final result on the trail.

Sorry... I am a cannon nazi

[mrlonewolf]

Awesome.

Good job.

[rero360]

The trunnions are going to be .75" in diameter, and currently that band of metal is roughly .90" the plan was to leave extra material so it give me something to work with when I put it all in the mill so everything can be blended in nice and cleanly.

Proportion wise, its not to a particular scale nor is all the features on the gun to scale with each other, its done the way it was due to the cutting tools at hand and me being super overly cautious regarding safety as I do plan on shooting it, possibly even attempting to send some cast lead balls downrange, see how it holds up to just blank charges with some tin foil as wadding.

I made sure to have over one caliber of material on all sides of the bore from the trunnions rearward. and it should be right at one caliber or slightly under at the thinnest point, need to measure it again. So its 1.97" +- .01" behind the trunnions, so having a .50" bore, thats .735" of material on the walls.

Not sure what the chase is, but the portion of the cannon between the muzzle and the trunnions has a 2 degree taper, don't remember the others off the top my head, all my drawings are at work.

[MountainShooter]

You are doing a fine job. That is one heck of a school project!

[GMG]

You sir are very talented !

[bcrich]

You've got some skillz!

[rero360]

Thanks gentlemen, I also intend to put a chamfer on the muzzle and ream the first quarter of an inch or so to open it up a few thou to aid in loading and to increase the life span of the cannon.

Total cost so far, not including machine time, tooling, labor or the hardware, mild steel and the Aluminum and brass, $110. most of the cost being the 4140, with the wheels taking up the remainder, and 2 bucks for the pins lol.

[yuccales]

That looks great! Great pictures also.

[ptoguy2002]

Awesome !
Some wood would look great on there too.

[h0use]

wow thats very nice!!

[DREADNOUGHT78]

Awesome! Cool to see something other than an AK/AR here!

[adamsreeftank]

That's looking really cool. I'd love to do a project like that.

I'll be curious to see how you mill the trunions and blend the cannon around them.

[rero360]

In between doing actual work I managed to get some work done on the trail of the carriage. I did a rough layout and then giving myself a healthy padding, I rough cut it out on the band saw.





So all I need to do now is finish the contour on the trail, drill and tap a hole on it for the elevation screw, create the trunnion caps, drill and tap the holes to secure them to the side plates, and do the finish work on the cannon that I mentioned above.