Well, as part of my refurbishment of the cannon I built 50 years ago, I am replacing some of my high school era home made parts with more correct versions. I started off replacing the (home made*, hand bent*, sneezed together with an old stick welder) trail handles with some castings I acquired from Ken Creswell in Knoxville, TN. I had to drill new holes through the end of the trail for the 5/8" bolts that hold the handles on. But the trail is tapered on all four sides, so trying to get a hole to come out on the opposite side (without taking the whole gun apart and setting it up in a drill press) was a bit of a $#@* shoot. So taking a cue from Dave Rase and Mr. Boggs on their tools for putting lug holes through a rifle stock, I built a giant version with brass sleeves for various size drills. Here is the drill guide.......
And the guide set up for drilling the cannon trail.......
Trail handles installed.......
Later I tell the story of the new pointing rings on the end of the trail.....another story of replacing parts either left off originally or parts that were compromises way back when.
* When I started making all of the "irons" required to build a full size cannon, it became immediately apparent that I was going to have to make some compromises on the authenticity of what I was building. All of the original irons were either cast or forged and were well beyond my capability to manufacture as a high school kid in the garage in 1970. With no equipment except access to a cutting torch, a Wildcat grinder, hand drills, hack saws, a really old Lincoln stick welder, and a sledge hammer, I started making all the iron parts for the carriage as close to being historically accurate as I could. I didn't even have access to an anvil, but there was a manhole cover in the street in front of my childhood home. If an iron part needed to be pounded into shape, I would heat it in a mud forge I built in an old wheel barrel (to make it portable). With the forge set up it up in the front yard, and watching for traffic, I would take the hot iron out to the street and, using the manhole cover as an anvil, would pound the daylights out of it until it needed to go back into the fire for a reheat.....or until a car came along and forced me to stop for traffic.