Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

   Do you mean "trunnions", not "tenons"? The latter term typically refers to parts of wooden joints, and while there are parts of the wooden cannon carriage that can be considered as "jointed", none of those parts include "tenons".

   So, I assume that you mean trunnions - the bars on the sides that mount the cannon barrel to the carriage? Those trunnions are scale-correct, and are perfectly adequate to support the barrel for firing a .490 lead ball using the correct charge (for a .50 bore) of about 45 grains of black powder. The key aspect of a safely working model cannon is the strength of the metal used, in combination with the relative size of the bore and the barrel walls (standard being the "3:1" rule - the total diameter at the breech should be at least 3 times the width of the bore, and typically 2:1 at muzzle). Along with (of course), never overloading any barrel beyond safe capacity.

   This model barrel meets all standard safety specifications, and is made of the highest quality brass. It is certainly true that undersized trunnions can render a cannon less than ideally suited for firing (and in extreme cases, even unsafe), but those aspects are far less significant than the overall strength of the barrel construction. But these trunnions are not undersized.

   I am not a machinist (but I count some of the very best cannon-makers as friends), but I do have a collection of almost 300 functional cannons (ranging from tiny antique toys, to modern mortars that can fire a cement-filled beer can 300+ yards), and have fired various models in competition meets (where rules of safety are very strictly enforced). I would never list any cannon on any venue (as a working model) if I had the slightest doubt as to its safe integrity.

   I see that you mention "ice" as some sort of "projectile" that you have fired? Apparently you are not aware that the use of any moisture-laden material (even wet newspaper) is considered one of the most dangerous mistakes that anyone can make when firing black powder cannons. There are numerous known instances of catastrophic failures involving wet newspaper, as well as the use of potato slices, apples, etc... (some fatal). "Projectiles" or wadding of any kind should never, ever contain any significant water content, whatsoever. "Ice" ??

   I appreciate your comments of concern, but do find it necessary to defend my presentation of this model as being safe, as described. As should be obvious, I did not present it with any great encouragement that it should be used to fire lead balls - the only purpose for that would be to try to hit a target, and it is a poor choice for that task. But I only collect working models, and I know what the standards are for safety.

  Here will post a couple of photos of a tiny fraction of my collection. These were made by some very prominent current and former cannon-making machinists. The middle cannon in the first photo is ex-Washington Naval Yard, an actual museum arsenal model (with rifled barrel), part of a de-accession in the early 1960s (a 60 ponder naval Parrott rifle). The gray cannon is a 1/17 scale model of the Armstrong 100 ton gun, one of only three examples made by a collaboration of three master-builders (it fires standard steel pinballs, and is pinpoint-accurate at 100 yards). Two of the builders previously worked as quality-control contractors for the US Government (including the DOD and NASA).

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