Side and top view with magazine
Front view with magazine views
Cannon on base without magazine
Basic Cannon top and side with full size ruler
Actually this is incorrectly based on a Mk4 Cannon which is shorter than the Mk9 and has a different shape magazine
The objective is a (possibly operational) 1/20th scale 37mm Canon.
Excuse the base on the photo above, this is actually the tripod base for the 20mm Oerlikon Cannon and if you look at the photo for that cannon it shows the correct base for the 37mm. In fact the Mk4 cannon was sometimes mounted on this type of tripod base.
This Cannon (anything bigger than 20mm bore is apparently a Cannon) is fully made of brass sheet, tubing and rectangular sections and soldered with normal 60/40 tin lead solder, I guess that's the electronics background coming out. But get some good quality water based liquid flux and the joints will be much stronger and the solder will flow much better.
basic barrel and magazine parts
Basic 37mm Cannon (in 20mm cradle and tripod mount)
Add a recuperator and shell casing chute
This shows the tapered barrel, tapered with a file in the stand drill.
The finished gun with handles etc.
The basic cone for the correct base cut from 10 thou brass with the 'good' scissors
Soldering those little feet buggers on was a real problem, I had to hold them with a pair of needle nose pliers and hold the flat part of the pliers on the bench to get them the same height, some I had to do again because the pliers are not symmetrical and I didn't keep them the same way up.
The Cradle is a bit fiddly but OK to make, basically cut brass out, fold, drill holes, and then file a lot. I bent it over a piece of hard square section steel (key steel) in the vice with a bit of persuasion from the hammer, it's a bit difficult to line it up properly, hence we don't drill or file first!
Ah the shell's - they're coming one day - 2mm brass rod!
The original Patent
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