O2 regulator trouble

My oxy regulator quit working. I took it apart and found the problem and put it together and it appears to be working but I have 1 part left over and would like to know what it was for.

The bottle pressure comes in to the 1st stage regulator; the seat is plastic and there is a tiny ball held against the seat by bottle + spring pressure. The 1st stage spring pushes thru a diaphram against a 'piston', a mushroom shaped piece of (aluminum?) with a thin tit that unseats the ball when the spring overcomes the bottle pressure against the ball. When Oxy goes thru, the intermediate pressure 'weakens' the spring force and allows the ball to reseat.

The original problem was NO FLOW at all. Examination showed the tit was battered and too short to unseat the ball. A bit of work with a fence pliers reshaped the tit so it was a few thousands longer and the regulator worked. Although it appears to work, I have 2 issues. One is there was a thin piece of metal, apparently between the tit piston and the 'cylinder' it rode loosely in. Loosely because the gas flow had to go around the 'square' part of the tit piston and the round 'cylinder'. This was a very small shiny thin curved piece of metal and I don't know what it was supposed to do or how it was supposed to fit.

The other issue is the mushroom shaped tit piston; I doubt my metal reshaping is going to last. I would love to find a correct part for this Craftsman 20 year old oxy regulator, any ideas who has it? Or else I could chop off the tit and drill out the mushroom and press in a better piece. Tricky but not impossible, but I would have to take extreme care not to introduce ANY oil since this is an oxy environment. Any clues? I guess I should use Al for a new tit? Any hepl appreciated. Nick

Reply to
Nick Hull
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I just bought 2 Victor SR 450 D regulators on ebay, separate deals, average delivered price was about $40. One was brand new never used.

With prices like that, why not just replace it? True, the SR 450 is a single stage, but it has a nice big diaphragm and you can buy every single part. And two stage regulators don't go for all that much more these days.

I vote for replacement, and considering that old Craftsman has earned its retirement.

GWE

Reply to
Grant Erwin

Why not simply get it rebuilt? Its about $25 most places. Beats having a sudden high pressure oxidizer leak when you least expect it.

Gunner

Political Correctness

A doctrine fostered by a delusional, illogical liberal minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.

Reply to
Gunner

Actually I already replaced it, but thought I could fix this one for a non-critical use since it's just one tiny part bad.

Reply to
Nick Hull

Free men DONT own guns , slaves own guns to fight for their freedom , but it never works .....

single stage reg can work at hi press if the volume is large and it has somethin to prevent oscillation at the valve , and the jet is small .

Reply to
werty

I'm not the super-anxious-type. But for stuff like this I don't hesitate to spend the money to get the job done in the right way. When I didn't use my regulators for about 10 years, I gave them for an overhaul and maybe spent

80$.

Not in your case, but just as a warning: When you make new parts -I would never- be aware that you can't use brass-alloys with more than 60% copper in acetylene-regulators. Or the thing will explode.

Nick

Reply to
Nick Mueller

It worked at least once, in 1776 ;)

Good info because my application would be very small flow.

Reply to
Nick Hull

Blink blink..so the head injury isnt doing so well is it?

Political Correctness

A doctrine fostered by a delusional, illogical liberal minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.

Reply to
Gunner

Nice to know that. I figured there was a reason the part was made of a soft alloy, looked like al or zamak. The body was made of some brass alloy.

Reply to
Nick Hull

And, there's a HELL of a lot of things you can't put into an Oxygen regulator. Teflon is good, certain synthetic rubber-type materials are acceptable, and stainless is good. Anything else I'd want to know the exact alloy, and previous history to make sure it didn't absorb anything flammable. Exposing any mystery material from the junk box to pure Oxygen at 2000 PSI is close to suicide!

Theoretically, even a fingerprint inside one of these regulators could cause a HUGE flaming explosion when you turn on the bottle. Once you get something hot, practically any material will burn in pure Oxygen.

Jon

Reply to
Jon Elson

This is a slow process, so you could replace a part, and then YEARS later, when removing a fitting, or just totally at random, the thing can blow up with energy approaching that of a rifle cartridge.

Jon

Reply to
Jon Elson

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