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I have an older kit that did not come with cannon.I have a good quantity of lead bird shot and would like to try to cast my own.Any tips as to how to go about this?

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It would be better not to use lead for a number of health related reasons, as well as the possibility of the cast lead pieces turning to lead salts later on. 

 

I recommend taking a mold in RTV rubber from your master pattern and casting with lead-free pewter. All you need is available through such companies as Micro Mark. Please read up on metal casting techniques. You need to have risers to allow air to escape and observe other safety precautions.

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 You can melt aluminum, if memory serves at about 1300°F, iron and brass is about 2100°F.. You can get a pot of aluminum to liquify by using charcoal or gas as a fuel, the web has much info on sand molding and furnaces. You are thinking along the same lines as myself about casting the guns, using castings you can cast the trunnions in, that is a big plus to me. What is running around the back of my mind is casting them using the lost wax method, maybe I will need to go to the art department at some college, that does bronze figures, they probably use induction furnaces.

jud

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I've cast many parts over the past few years including cannons, anchors and windlass parts. I've always used pewter alloys. With a melting point below 600˚F, you don't need access to a special furnace. Pewter alloys are easy to work with using just an iron ladle, a MAPP gas torch and RTV silicone molds (and safety equipment!). 

 

Not sure why you would want to use lost wax castings. I used to hang out with my father, who had a small lapidary and jewelry business. He used to use lost wax castings for gold rings. You have to make a wax pattern for each item your going to cast and then you destroy the patterns in the process – it's a one-shot deal. Great for sculpting unique works in wax and casting them in metal. But, it seems like there are easier ways to accomplish what you need.

 

Of course, depending on what cannons you need, you might simply consider buying them in pewter from The Lumberyard or buy turned brass barrels from Chuck Passaro if the available sizes will work for you.

 

If you really want to do you own castings (it is pretty fun to learn), you can get everything you need from Micromark except the torch and safety gear.

 

Clare

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The lost wax process produces very good castings, you make one mold to produce the wax patterns, you then can produce as many wax patterns as you want. To create a mold from those wax patterns you build what is called a tree using your wax castings and connect them all together with wax runners and risers in a manner that will all fill the whole mold and vent  the air out. There needs to be cavity's  in the mold that allows for enough mass so the desired castings can draw molten material from, to fill any voids created because of the faster cooling of the smaller castings. When the tree is completed you build the real mold around the tree, when made, you melt the wax out of the mold. You can produce 10 or more cannons per pore this way. Jewelers use the lost wax process because it creates very detailed and sharp castings if the final mold material allows for that, often two mixes are used, fine material against the wax, usually brushed on, and a courser mold body.

jud

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The lost wax process produces very good castings, you make one mold to produce the wax patterns, you then can produce as many wax patterns as you want. To create a mold from those wax patterns you build what is called a tree using your wax castings and connect them all together with wax runners and risers in a manner that will all fill the whole mold and vent  the air out. There needs to be cavity's  in the mold that allows for enough mass so the desired castings can draw molten material from, to fill any voids created because of the faster cooling of the smaller castings. When the tree is completed you build the real mold around the tree, when made, you melt the wax out of the mold. You can produce 10 or more cannons per pore this way. Jewelers use the lost wax process because it creates very detailed and sharp castings if the final mold material allows for that, often two mixes are used, fine material against the wax, usually brushed on, and a courser mold body.

jud

 

I don't understand the "tree-method". Could you provide a picture, maybe a creative paint version? :)

I'm interested, as I'm planing to make a set of cannons soon.

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I would seriously consider doing the cannon in resin. Once agian Micro-mark has the whole kit and theres a ton of videos on the subject. Specially if you look up Smooth-on or other sites. Metal cannon these days are highly over rated with all the cool  finishes one can get for plastics and resins. BILL

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Krulzelpuntz: 

http://www.castem.co.jp/lostwax/e-tech.html.

 Just one site that will show and explain the process much better than I could ever do, you will see that the tree is only a structure built from the wax patterns themselves, all joined together so one pore will fill them all. I would think that the method could be adapted to using resin, might require an injection device or a large sprue so the mold can be filled from the bottom to prevent voids.

 Casting metal guns, just as casting resin guns can be rewarding in itself, it also is knowledge that could be applied to other needs. Have read that molten metal, pored into a sand mold was the plastic for the world for hundreds of years and castings still are produced in great numbers. Few small foundry's have survived, but the means and reference material for an individual  to produce their own casting, still exists.

jud

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Long ago in a former life I took a class is lost wax casting.  We used plaster to make the molds and cast brass and gold items.  These were single use molds.  Easy to make and would work just as well with pewter or Brittanina.  An advantage of using plaster is you can pre-heat the molds which gives a better casting result.

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Krulzelpuntz: 

http://www.castem.co.jp/lostwax/e-tech.html.

 Just one site that will show and explain the process much better than I could ever do, you will see that the tree is only a structure built from the wax patterns themselves, all joined together so one pore will fill them all. I would think that the method could be adapted to using resin, might require an injection device or a large sprue so the mold can be filled from the bottom to prevent voids.

 Casting metal guns, just as casting resin guns can be rewarding in itself, it also is knowledge that could be applied to other needs. Have read that molten metal, pored into a sand mold was the plastic for the world for hundreds of years and castings still are produced in great numbers. Few small foundry's have survived, but the means and reference material for an individual  to produce their own casting, still exists.

jud

 

Thanks for providing the link! To me it seem easier to do it the old "2 part mold", as I probably won't be making over 12 cannons. I also like the idea of keeping the mold :) the tree method would be for a larger amount of moldings i recon??

 

Regards, Jakob!

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I have gone to making and using a single piece mold and eliminated  the seam and vents.  Works very well for casting resin or pewter. I  will try to post details and pics tonight

Allan

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Janos,

 

I am about 2500 miles from home, but will be back this weekend.  I need to reformat the write up and resize the photos from the original used in the Euryalus book.   I do not understand how you broke the bold.  Was it made with a RTV silicone rubber or something else?   I made about 20 barrels with the same mold and it is still in good shape. 

 

Allan

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Hi, Folk,

just browsed this subject as I am interested in casting Canons in brass or bronze bigger than model size's! and wondered where the thread would lead?

some interesting comments and suggestions, but I cannot fathom out ( if I ever attempt this) how to machine the Trunnions after casting?

any  one got a comment on this??

 

Frank

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Here's a cannon I cast in white metal (tin with a couple of alloys to improve flow).  These are straight out of the mold, 1/64 scale 6 pdr.

 

Your issue with casting metals is finding RTV rubber that can resist the heat.  Most RTV rubbers that you find have heat resistance in the low 200deg C.  Brass/ Bronze melts at over 700C so you'll need to be using lost wax and other mold material (look at jewlery casting).   White metal melts just over 300C.  Your lead alloys melt lower and flow well, but as mentioned they have downsides.

 

The upside of metal casting is "fails" go back in the melting pot.  Resin casts that fail are wasted material.

 

Colin

post-6015-0-04883700-1388281807_thumb.jpg

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Philo,

 

Take a look at the  www.vasamuseet.se site and go to the "Creating the Cannon" section. You may find it more enjoyable giving a shot at making your own master barrels. 

 

Allan

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Hi Jacob,

Thanks for the reply, have only just found it after over two years? you must think me very ignorant! the cannon I am thinking of would be about 8"

in the barrel lenght. but untill i have some idea of how to machine around the trunnions I will not attempt it. I have a small lathe but it has not the capacity to swing that length?

regards Frank

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Just noticed this thread picked up again.  If it matters after all this time,  I used to use materials from Micro Mark and it was no problem, but then changed to Polytek in Easton Pennsylvania as they specialize in resins and silicones and are experts in the field..  You can discuss your project and problems with them and they will suggest the proper product.  I do not have any materials on hand right now so cannot tell you which one I used.   Relative wall thickness is important.  Better thicker than thinner.Allan

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