tank manifold question

[ianr33]

Today if you mention doubles it is automaticly assumed that you do cave or tech diving. Such was not the case in the past.

That was my assumption.

Lots to learn from you old timers

 

[Colliam7]

the thread on these manifolds is 3.25"around ... if i wanted to advertise on my ebay ad that they fit standard tanks how could i express that? do is say its a 3/4 thread or what exactly?

It would be hard to say how to advertise it, simply on the basis of the thread description you have given. You would want to say 3/4 NPS or 7/8 UNF, as long as you are certain which it is. If 3/4 NPS (for sure) then 'standard' may be a word that you could use. Not knowing anything about the history of this manifold, however, I can't tell from the picture or your description if it is one of these thread forms, or possibly a (slightly different) European version. The bigger issue is the market for this type of manifold, as several people have mentioned. It is not a matter of whether it is 'that bad'. It is simply not going to be considered a safe and functional manifold for most people diving doubles - no isolator or individual valves, a yoke connection instead of DIN, etc. It is not even a matter of cave vs tec vs recreational. The number of people who want to dive doubles outside of the cave / tec community is small - yes they exist, but there are few of them. Many of them are also cave or tec folks who dive double AL80s or something like that for convenience on recreational dives. And, most of them are using DIN regs in that case, not yoke. Nonetheless, it certainly is an interesting item, and the 'vintage' label may be the most effective marketing approach.