The difficulty I have with casting cannons is that my wax models are at the maximum size of my tallest 7 inch casting flasks. They are also big and solid, in that they weigh approximately 285 grams when cast.
My casting today was for two cannons and one carriage. This took 890 grams of silicon bronze which is just shy of two pounds of metal. My furnace can melt this much metal, but I do sometimes worry when handling this amount, particularly if my metal pour fails.
My cannons have a hollow bore. This means that there is about a quarter inch thick column of investment running up inside the cannon. I suspect this column can easily snap when I pour the molten bronze because it has no support at the fuse end. Frankly, I have yet to successfully cast a cannon that had a complete bore.
This time I drilled two 1/8 inch pin holes in the wax at the fuse end of the cannon. Hopefully, these pins will be strong enough to ensure the cannon bore remains hollow after I pour the bronze. I will find out when I detach and clean the casting?
If I do get a full bore then I can make some gunpowder and see if I can fire the cannon! Stay tuned …
Update: Yes! My cannons have a full bore … my mad scientist antennae are vibrating …
I also cast my Faerie Twig and Leaves, and some related Faerie items and shells in white bronze. Pictures follow.