How to trunnion installation and search function

[befunovo]

Hello all, new to the board.

First of all, I looked under the help section and read up on the search function.  I must be an idiot, I could not find it. 

Trying to search on how you typically install the trunnions on a brass cannon. 

I am making a simple little naval style cannon.  1.5" dia x 6" long with a 1/2" bore.  Not going to be used to shoot hard, more looking at lobbing shels at soft model targets for fun.  Anyways, do you braze or silver solder them in?  I was hoping to polish the cannon up, not sure how the heating will effect the final color.

I have a lathe and a mill with a rotary table on it, so getting the trunions in the proper position will not be an issue.  My current thoughts are to mill a hole out in each side of the cannon for the trunnion piece to lightly press into.  Then hit it with the torch and silver solder them in.  Or can they be pressed in?

As a newb, please feel free to point me in the proper direction.

Brian

[gary michie]

  HI:
 Brian you are singing my song..... Safe loads and cannon plans does not say look here if you need help with your carriage,trunnion,a differant vent,paint color, how do I make 20" bolts and so on....I've been here for over a year, finally, I ask for a How's it made page and am informed to look at Safe loads and--------.OK ,some input, but guys here are talking about how to do this a that all the time and have GREAT ideas and those differant solutions are here some where ,but where?You really have to go and search. NOT FUN.
OH yes by the way wellcome to GB this IS the best cannon and mortar site I have found with a great bunch of people.

[GGaskill]

My current thoughts are to mill a hole out in each side of the cannon for the trunnion piece to lightly press into.  Then hit it with the torch and silver solder them in.  Or can they be pressed in?

Recoil is what you need to overcome and that is a function of powder charge, shot weight and barrel weight. 

For a small gun, silver soldering sounds appropriate and would be OK with a steel barrel.  However, the temperature needed to melt the solder will anneal the brass which will make it softer and less strong.  Some other high strength but lower melting point solder would be a better choice.  I would make the trunnions a slip fit so the solder can flow down between the trunnions and barrel instead of being limited to a fillet between them.  That will be a stronger joint.

The heat will change the color of the metal but it can be polished back to the original color.  Only the surface is oxidized which is what causes the color change.

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The search function that came with the forum software was very resource-intensive (it used up most of the server capacity) so the webmaster replaced it with the Google search.  The downside is that most of the archives are in an old format that is no longer readily available through the url's returned by Google.  Over the years this will improve but for the moment, you really need to read the whole thing to find what interests you.

[Double D]

HI:
 Brian you are singing my song..... Safe loads and cannon plans does not say look here if you need help with your carriage,trunnion,a differant vent,paint color, how do I make 20" bolts and so on....I've been here for over a year, finally, I ask for a How's it made page and am informed to look at Safe loads and--------.OK ,some input, but guys here are talking about how to do this a that all the time and have GREAT ideas and those differant solutions are here some where ,but where?You really have to go and search. NOT FUN.
OH yes by the way wellcome to GB this IS the best cannon and mortar site I have found with a great bunch of people.

Gary,

I am really sorry you find our board inadequate for you needs.   There is only one thing I can suggest you do.  Do like the rest of us.  When you ask a question and nobody has the answer, figure it out yourself and make a post sharing your knowledge. 

If you got pointed to the Safe Loads and Cannon plans post it was because the answer to your question was there.  As people post up ideas on how to do things we try link them in to the Safe Loads and Cannons Plans post. We may have pointed you to the Safe loads and Cannons plans when we should have pointed you to the FAQ's, but your answer was there.  That's where the paint formulas are in the FAQ's. Maybe I need to pull some of those ideas into the Safe loads and Cannon plans post.

Nobody has written a post on making 20 inch bolts or vents.  If you have made those things a tutorial post would be most welcomed. Gary you put up a post showing an axle.  How about putting up a complete post with pictures describing how that axle is made. This is how we get things for linking into the Safe Loads and Cannon plans.

We are not the be all/end all and don't claim to be. We here on the board don't have the answer to every question. But we are all willing to share our knowledge or point a person in the right direction when they ask.

To be quite honest Tim and only started this board, because we didn't know very much and wanted to learn more, and learn we have.

If you ask how to install trunnions in a brass cannon and no one responds it may be because no one has installed trunnions into a brass cannon.  Or it may be the guy who has, only visits the board once a week and he hasn't been by yet.

[jeeper1]

Here is one way of installing trunions on a bronze tube.
http://www.graybeardoutdoors.com/smf/index.php/topic,71341.0.html
Bottom of the first page and the top half of the second page.

[Cat Whisperer]

...
  Anyways, do you braze or silver solder them in? 
...
  My current thoughts are to mill a hole out in each side of the cannon for the trunnion piece to lightly press into.  Then hit it with the torch and silver solder them in.  Or can they be pressed in?
...

Brian -

George has given you a good perspective.  Let me just add that brazing or silversoldering trunions onto the bore takes a HUGE amount of heat - not a simple task.

[Michael Az]

I think Cat is right, it is going to take a lot of heat for silver solder.
Michael

[GGaskill]

It might be possible to Everdur the trunnions to the barrel using a TIG welder but that would be an experiment based on my experience (I am not a professional welder.)  That would be a strong joint and limit the heat input compared with oxyacetylene but the barrel would still get quite hot unless the process was done in very small steps with cooling in between.

[gary michie]

  HI:
Drill and bevel the edge so you have a place for a deep fill then in set the trunnions in to the barrel . I would Oxyweld them in place useing like metals that way you have a weld not a glue job as any solder application is. look at this web site
http://www.artmetal.com/brambush/forum/bramyak3/messages/23.html

[Rickk]

Oxy/acetylene or oxy/propane brazing would be awesome for strength, but you will have to preheat the whole thing up or you will never get the base material hot enough for a good intermetalic bond. Having never done anything that big, I have no idea how much preheat you would need. I have done a lot of brazing on 1/4 inch or thinner steel. It has to be obviously/visably hot for the braze material to flow nicely.

Gas welding would be way harder than brazing.

Silver solder and the right flux would melt and flow way easier than brazing rod.

Brazing/soldering goes under and in between the pieces (if done right - hot enough), while welding is mostly in the neighborhood of the visable joint. That means that you can get way more surface contact area if you braze or silver solder. Even if the tensile stregth of the materials is less, brazing/soldering will be stronger if you can get it in between the joint rather than only on the edges as you would with welding.