Well this is what I have been passing away some of my time on lately. It stood on the work bench for a very long time. I traded part payment of a job for the cannon and all the moulds to make more. It is made of cast iron and has a steam pipe for the barrel about 7/8" bore. The barrel is 500mm long. It is scaled down off a deck cannon from Cpt Cook's Endeavour when it was pushed overboard to run aground at 1770 for repairs. when the cannon was found and retrieved my client was there and he worked in a foundry up North. He scaled the whole thing down from casts that he made of different parts of the cannon even the Crown that is on the barrel is as good as you can get this small. He still has the original casting of the full size crown on his wall at home. With mine I made some small pegs to drive into the ends of the axle to hold on the wheels. I also used some 'locktite' and then put a small bend in the peg to keep it in place. I also managed to get the moulds both positive and negatives so that more can be made if and when needed. Only need a foundry to do it.
