photos of my project

[guzzibill]

Here are some photos of my 63.5mm cannon. thanks to those that steered me in the correct path for the chamber.  I hate the color of the barrel, It was supposed to be antique bronze... I am going to have it striped and recoated with "copper vein / black"... mostly black with copper vein's underneath. I still have some iron trim and hardware to fab also, but its gonna look pretty good in the end... http://www.flickr.com/photos/19323179@N03/sets/72157617492288040/

[Ex 49'er]

That is a good looking gun. I really like the way the carriage came out. Great grain in the wood!
Thankyou for sharing.

[GGaskill]

You might give Rustoleum Burnished Brass a try.  I like it.

[Cannoneer]

Guzzibill, I really like the look of your barrel and carriage, but I'm guessing just by looking at the placement of the trunnions on the barrel, and also from noticing the placement of your hand on the cascabel in one photo, and by your finger under the muzzle in another photo that your gun is muzzle heavy. You have discovered what is called preponderance, and in a field gun the breech end of the barrel should always be heavier (when balanced on the trunnions) than the muzzle (front) end. The welder that attached the trunnions, placed them too far towards the breech. The two easiest ways to remedy this situation, would be to either make the cap squares that hold the barrel on the carriage press down very tightly on the trunnions, or (even better) to have the top of the elevating screw attached (under the cascabel) directly to the barrel.

[Double D]

The preponderance bothers me also. The Trunnion placement looks okay in this picture.
 


These pictures sure seem to show its wrong.  This is what Boomj is talking about.


.

If that Cascabel is solid and the Breech plug was constructed properly it would seem that the weight would be sufficient to balance correctly.  Also there seem to be little to no taper to the barrel and it doesn't look right.



If the barrel was a little more tapered it would shed some weight forward and perhaps move the perponderence.  What ever is causing it, you need to fix it.  When firing the gun the recoil is going to work on that and eventually cause problems.

The barrel looks powder coated.  Try the burnish brass George is suggesting or just a gloss black.   When you paint your carriage and iron works it will look a lot better

[guzzibill]

 I believe it will be OK, the photos were taken by my brother, ( we are working on it at his place).
 When I dropped it off, he wasnt home, and he thought that the bag in the front of the barrel was just a paper bag to plug the barrel when it was powder coated .... in reality it is a four pound bag of square head black iron 5/16 wood screws.... removing the bag of screws from the front of the barrel ought to change things a bit !  when I located the trunions, I found the balance point then moved back a quarter inch. after I did that, I had the chamber bored into it ( 1.33 X 1.6 of steel removed to form chamber) so it must be pretty close to neutral ballance at this point.... the taper is from 3/4 inch wall to 3/8 wall at the muzzel, and starts right at the trunions. I tell you what... it sure seems ass heavy when I pick it up. 

[Double D]

4 lbs of nails, might have an effect. Dumb Brothers!!! I can say that because mine doesn't read this board, I don't think.  I'll know real soon if he does.

 For future builds find the point of balance and move forward.  I can see the taper in the stand up pictures, but not the others....photography has a way with messing up the angle of the dangle. If the barrel was a foot longer with that taper you would see it.

Are you bringing it to Montana?

[Cannoneer]

Well, alright then Guzzibill, I'm glad to read that your tube isn't front heavy, because this means that you have no problem, and that a lazy guy such as myself, now doesn't have to spend time posting any photos, and/or drawings, trying to demonstrate what I meant by attaching the the elevating screw to the underside of the cascabel.

[guzzibill]

I havent addressed the elevating screw yet..... I have a brass acme screw and the brass collar that it threads into from a 6 in. OS&Y water valve that will make a good elevator... I just need some small handles to attach to the stem, and fiqure a way to mount it on the trail.... or a source of a premade one thats reasonable... my only problem is the screw box itself, the collar I have is flat, no offset, so in order for the stem to rise from the trail at the right angle, I will need either to inlet the trail  or add a wedge of wood to it for the collar to sit on... and I am not fond of either idea. maybe I will break down and just buy one. problem is, I only have about 4 &1/2 inches between the cheecks and most elevators I have seen have handles that are wider than that.  one way or another, I will work it out. as for attaching the elevator to the casabel, I have done that on another cannon, so no need to describe it.. but thanks for the thought.

[kappullen]

I wonder if DD's gun is muzzle heavy?
He has the breach held down with a rope!

I read somewhere the breach needs to have 10%
of the weight on it, to avoid the muzzle down condition
after firing.

That information was in one of the historical Civil War
re-print plan books.

Trunnions want to be on or below center to avoid barrel
float.

Kap

[Double D]

Nope sure not muzzle heavy, and with the rope, no longer a secondary projectile.  Good enough for the old real ones, good enough for me.

[RocklockI]

no clue on the color 

but that is one nice looking cannon and carriage

gary

[Frank46]

Preponderance or when the trunions are too far back. What is the rule of thumb to detirmine where the trunions should be?.
Great looking barrel by the way. Frank

[GGaskill]

You can mathematically calculate it by summing all the various masses and centers of gravity or you can take the finished tube sans trunnions and balance it and drill pockets for the trunnions slightly toward the muzzle from the balance point.

[dan610324]

if you follow the old proportions used in the 17th and 18th century the trunnions should be placed at 3/5 or 4/7 of the barrel length from the muzzle

[Frank46]

George and Dan, thanks for clearing the trunion location mystery (for me at least) up. Frank