There have been some other threads on the forum about the NAVCON VI and military standard (MIL-STD), also known as NONMAG, Conshelf model single hoses. I would like to use this thread as a catch-all thread for the NAVCON VI, as I recently acquired one from Roger AKA Robohips. Mine, as far as I can tell, is original minus the exhaust valve which Roger replaced for me with a modern silicone one. As Bryan mentioned in a previous thread, there do not appear to be any gold plated, line scribed, or non-magnetic stamped parts in any NAVCON VI regulators. There are NONMAG inner parts in the NONMAG conshelf. You can effetively consider them two different regulators, although they both appear similar in outward appearance.
The best I can tell, as I have it soaking in some 50/50 white vinegar and water, is that this looks like a military NONMAG single hose without the inner NONMAG parts. I can only surmise that USD had some extra bodies, hoses, and housings left over. They probably threw them together with normal innards and sold them. Mine certainly appears to have a normal second stage lever and poppet, and it doesn't have any gold plated parts either. As I rebuild this regulator, I will post anything that I note of difference from the regular Conshelf VI series of regulator.
Interestingly, and you can see this in the photo, the main body of the second stage is that of the later model Conshelf XI/XII/XIV style regulators. It features the much larger exhaust profile of post Conshelf VI series regulators. The front can of the second stage is the same as a Conshelf VI. You can also see the longer yoke and the post Conshelf VI style exhaust tee. The exhaust valve is a modern replacement.
Differences from standard Conshelf VI (I will update this as I find more):
-Black finish
-1970+ style second stage case body with larger exhaust port
-1970+ style exhaust tee
-1970+ style longer yoke
For reference, this is what the 1969 USD catalog shows, which is the last year of the Conshelf VI:
As other mentioned in an earlier thread, note the reference to the MIL-STD regulator, which makes mention of containing the low magnetic signature parts.
For reference, this is what the 1970 USD catalog shows for the then new Conshelf XI:
I would gather that the single hose MIL-STD (NONMAG) and NAVCON VI regulators were both made in the 1969-1970 time period. This makes sense, as it uses the pre-1970 first stage, but a post-1970 second stage. Additionally, to my knowledge, the MIL-STD regulator is only mentioned one time, which is in the 1969 catalog.
If anyone has a Conshelf NONMAG, I would love to know what the nonmag parts are and what they look like. If they are in keeping with their double hose counterpart, then they should be both gold plated and scribe marked. I would also love to hear from anyone else who has more information.