Difference between Conshelf 2nds

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I’d like to add a ‘classic’ = metal second to my ‘new’ doublehose (US Divers can with Phoenix second stage and DSV mouthpiece)

In terms of performance and parts availability, what is the difference between a Conshelf XIV and a XII?

The XII is going for less than half a XIV
I'd have to look at it to be certain, but most likely they are the same other than the sticker on the purge button.
That basic second stage had 3 different versions that I'm aware of... The Conshelf VI type with a scalloped purge cover, screw on exhaust T, and small exhaust valve. The Conshelf XI type with the smooth purge cover, larger exhaust valve, but still a screw on T. And the Conshelf XIV that has the smooth purge cover, larger exhaust, and press on T.
Now, because they are all parts interchangeable it is impossible to know which size exhaust is under a screw on T without physically checking (parts replacement over the years, and such). Also, those 2nds were used on more than just the Conshelf series.... So there are a whole slew of purge button stickers.


… not to mention virtually bullet proof and (if not shot with a bullet etc) easy to rebuild. In conversations I’ve had with @rsingler (IIRC) it appears that the only disastrous damage short of total destruction is damage to the volcano valve. I’ve got XIV and an Aquarius second stage box and plan to continue using and rebuilding them until they shovel dirt in my face or bury me @ sea.
I have a XIV first and second with the original 1085 octo that breathes like a dream. Rebuilt myself with the help from members here. I use a 1085 second (with a XII sticker on the purge) for my octo on my double hose rig and is a solid performer as well. I like the design, performance and ease of maintenance. And it's chrome plated brass of course.
Back to the comment about stick on labels on the purge button. These same stickers were also found on many of the yoke knobs, but in some cases they just were a generic “Aqua Lung” sticker. My Aquarius second stage looks exactly like my C XIV box except for its special black sticker, and replacements for some of the different stickers were available from some of the vendors up until recently. If I continue using my Aquarius second as an Octo, I’ll probably put a yellow exhaust T on it and try to find an Octo sticker, otherwise I’ll have a friend 3D print a yellow purge button. 😉

There's another late variant I've been trying to find for awhile - the 1085 style with threaded plug opposite the inlet, so preload adjustment can be done on the poppet nut without removing the purge cover. I gather the XIV models still sold to the military have this feature, but they seem rare on the secondary market.
Spoolin The Scuba Museum had one listed for sale this morning
Thanks, hadn't even looked there. Looks sold out now, but anyway they were 3x what I pay for a whole reg set, so not likely to indulge in one just yet. Several months back 5 new ones went up for sale on eBay for around $60 each, IIRC. By the time I put an offer in, they were snapped up. Maybe one day. Haven't had a chance to try them out yet, but I'm kinda liking the Dacor metal Pacer XLx models. The Dacor chrome seems to have been a cut above.
To resurrect this zombie thread, I’d like to ask whether there is any great advantage to searching out a late type 1085 second stage? Is that external adjustment screw something that actually gets used, or is it just left alone after the reg is tuned? As always,TIA for your experiences and informed opinions!

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