Two Stage Regulators...

[Bambi]

Now I have written about this several times in the past few days in other posts on welding, but apparently no one reads them.
How many in here know what a Two Stage regulator looks like???
How many in here even own a set???
Think they are the Hot setup for Aircrafter type torches or the Henrob units???
Surprize they are not.
You will never notice the difference, they weren't designed as many suppose for the low pressure and low flow that we use. They are designed for Heavy Cutting and Welding where the extra diaphragm and spring pressure act as a shock absorber to the flow of gas. It smooths out the flow when your using 80 psi on the Oxygen for cutting.
Funny thing is most shops even doing general fabrication and heavy cutting will still use Single Stage Regs.
OK here is where the problem is, NO ONE makes a regulator that is setup the way you want them. Take a gander at the guages on a Two Stage and a Single Stage Regulator and you will see that for the most part they are Identical.
There is one gauge that tells the Bottle pressure or how much gas is in the bottle and then there is the Line Pressure or how much pressure is being sent to the Torch.
The Acetylene Line Pressure guage will start at the pin and go up in increments of 1. Number 1 thru 4 will be a slash and 5 will be a number, more slashes and then 10 etc.
The Oxygen Line Pressure guage will start at the pin and go up in sometimes 4 psi increments, sometimes 5 or any other units, each slash being whatever is on the guage. The first real number will more than likely be 20. So figure it out.
For the accuracy freaks your in trouble as most gauges even new are very innaccurate, you will have to learn the method that I wrote up which is basically the same as the Dillon setup technique. Its called Neutral Flame. Each orrifice size has its limitation on flow and pressure where a Neutral flame can be had. You really can't go by a chart or by the gauges. Those can only put you in the Ballpark, then YOU have to figure it out and fine tune it.
Part of the solution for those that are posessed with having the need for a "proper" gauge is to have the welding supply house change the Oxygen Line Pressur Gauge. What they will probably do is change it using an Acetylene line pressure guage, but when you want to cut your on your own. An Acetylene guage you say, the gauge don't care what gas is run thru it.
As I stated Gauges are very inaccurate so I will run some numbers
OK for those that want Two Stage regulators, figure on $300 each
Now you want the gauge change, figure on anothe $25, if you do it yourself you VOID any warrantee.
Get a Dillon torch for $400, hose etc $50
But guages are inaccurate and I want calibrated gauges. Forget the $300 price tag EACH go for $1000 EACH
Add it up for the Henrob with Two Stage Regs, you got a $1000 invested and NO Tanks as yet.
If you want the Henrob with Calibrated gauges, you got $2400 invested and still NO Tanks.
Geez, I coulda bought a TIG Welding machine and I don't know how to use that either.
These Forums are Great and Talk is cheap. When the rubber meets the road, the problem is not in the Regulators be it Single Stage or Two Stage. Its the lack of the good folks going out and looking at the Regulator and seeing that the Line Pressure Gauge is a problem for some. Setting up the torches and getting pressures correct for a Neutral flame may be a problem for many. Accuracy of the guages are a problem to live with.
Henrob uses one of their own tips for calibrating, set it and forget it, no further need to look at the gauges.
Others will have to learn how to setup and go from there.
For the gauge lookers have the Oxygen line pressure gauge changed.
In a nutshell buy Single Stage Regulators and if ya want have the Oxy line pressure gauge changed.
Two stagin it won't help ya one bit.

Under Pressure
Bambi

[Gene_Olson]

How many in here know what a Two Stage regulator looks like???
How many in here even own a set???

I have a set, got them with a Victor cutting torch and a hundred feet of hose from a retiring junker for $100 (30 years ago).

All this talk about the perfect tools, reminds me of playing darts years ago. (For a while I was fairly good, not any more haven't played in years)
My friend had a whole raft of darts, tungsten, brass, light, heavy, fat, thin, . . . I looked at the stack and gave him a quizical glance.
He said, "I seem to be having trouble with my . . . and I thought I could solve the problem with a different set of darts."
I reached down, picked up the whole handful, added them to my own set of three, picked them out at random and started throwing at the board one right after the other, never said a thing.
All of them within about an inch of the bull.
Paul looked at the grouping and said, "You're right, it's not the darts."

If it's not the darts, what is it?

Expertice? and what is that. Talent yes, but applied skills you learn.
Some learn faster than others, don't fret.
Practice, yes, but practicing the right thing.
Practicing the wrong thing . . . you don't want to go there.

If you are having trouble, check the easy things first.

Clean? Settings? Tools? ( I thought I was going crazy the other day the way my tig welding was going, turned out a tack weld had broken on the foot pedal linkage and it was slipping PART of the time)(and yes there are those who will tell you it is too late for me to consider going crazy.)
Check things like: Is there something heavy sitting on the gas hose?

reread the posts on welding, haul out that old textbook and actually read it this time. (admittedly, very dry reading)

Like the darts, some of this is fine motor control. Making those hands work.
Loosen up.
It is hard enough to do it right without tieing yourself in a knot to start with.

G.

[Hemirambler]

bambi,

Yes I do know what a two stage regulator looks like. heck I even know what they are "supposed" to be used for. And I have even experienced the annoyances of a single stage regulator - yes even a "good" one.


Bottom line- the single stage regulator CANNOT maintain a precise output pressure over the entire range of bottle pressure. What does this mean??? Well likely very little to most - I agree especially if you're talking an O/A setup, because like you already mentioned the flame tells you what you need to know - the gages just keep us honest (and safe in some cases). Besides most who are gas welding sheetmetal are likely to be using relatively low consumption rates. Plus even if you weren't - heck the flames right there in front of you!

When I used to do alot of MIG welding with my single stage regulator (on a weekend warrior basis) I could deplete a bottle in a day. If I would pay attention I could notice the regulator would change it's setting over time a fair degree (as a result in large changes in bottle pressure). Was this insurmountable?? 'course not - but it was a factor needing addresssed (readjust it every so often).

So I guess in spirit I agree with you rcomments, but it doesn't make sense to me to just dismiss two stage regulator altogether either. IF you had a need for constant and precise output pressure well then you have pretty much defined what a two stage regulator is for. Now whether or not you can get these in a operating range that is appropriate is another matter.

I might make a price comparison - like how does a "cheap" two stage compare to a "good" single stage unit - in both performance, price, longevity.


Ah heck who am I kidding - I bought all my stuff USED - these choices are reserved for the "money" guys. <grin>


hey Gene, your comment reminded me of a saying I recently heard - it went soemthing like this:

Practice does NOT make you perfect....Perfect practice makes you perfect.


Makes sense to me.



Jacin in Ohio

[slobitz18222]

I have two of my sets of gauges converted to small numbers. I do reset them each time i use them as per henrobs directions. The other day when welding some aluminum I checked and rechecked my gauges and still could ni
ot get a decent weld till I checked my flux. I inadvertently used a jar of brazing flux and just pigeon --- the works. Changed flux and it was just like i relearned to weld.
I have four sets of single stage gauges and have no trouble with any of them, some are 40 years old.

[Bambi]

I have learned many lessons over the years. Yep I too was one of them wise guys that figured I would rebuild my own torches and gauges etc, gonna save a few bucks, how hard is it.
Simple things can be very complicated. It's not just takin the thing appart and cleaning it, it's making sure things are up to snuff and repairing it and putting it back together like new or better.
Sure you can take those things appart and do some of the work, guys can take Micrometers and dial indicators appart. Does that make them an instrument maker. Take a watch appart and then make it work. There are things that we may think we know how to do, how hard is it, but there are hidden things we may know nuthing about. In one of the posts someone mentioned that they would go to the hardware store to buy O rings and rebuild their torch. That is fine, they can take their life into their own hands. In the case of the O rings, many are sized and are of different materials.
Jacin you mentioned using Regulators on Mig setups, I have seen it done, they don't work well at all. A Flowmeter works much better and it ain't a Two Stager.
Now I luv my Smiths gauges, but I learned a big lesson years ago, Smiths makes a top quality Flow meter. So when I bought a new Tig machine to replace the old one, I wanted a new Smiths, but when the Salesman thru in a new Airco Flowmeter, I ran that one. Free is good. It sure was, my argon consumption was cut in half. They made a better flowmeter than Smiths.
One thing that many don't know is that many high pressure gas bottles have a double seated valve in them, they are designed to be either closed or wide open. I too do as many do, for a quik Mig or Tig job, I will crack the valve open and maybe give it a turn or so, then do my job. On a long job I have learned NOT to do that and open the valve wide open. Why??? Because most valves leak when in the inbetween mode. Forget doin a bubble check you will never find them. My gas supplier told me to do a test for a month and see and my eyes were opened. I did it with Oxygen which is a High Pressure bottle, there is no need to do it with Acetylene, it's not High Pressure. I lost almost a whole bottle because of wrong procedure.
As for torches and regulators, I too have done the rebuild on stuff, I hardly ever bought used stuff, figured there was a reason why they were getting rid of it and didn't want their problems. Some stuff I sent out and had it rebuilt, they painted over the brass, some even put grrease, yes grease on the Oxy regs, some weren't evn mine when I got them back. I was assured that the rebuilds would be just as good as having the factory do them at half the price. Bull.
So what do I do now, I save my money and don't buy someone elses junk, no matter how much I am tempted, my time is worth something and there ain't no deal. I buy new top quality name brands from dealers that I know and can go up and smack up side the head if need be. If I send something out to be rebuilt like in the case of regulators, gauges and torches, they go back to the manufacturer that made them. I don't get someone elses stuff in return, I get my stuff back or new. I am not rich by any means but I learned my lessons well. I also have seen guys that could rebuild anything and they screwed up their own torches and regulators to the point where they blew up.
There are many engineering types that are too hard headed to learn some things, it's too bad.
Some guys want to have Two Stage Regulators figurin it will solve their problems, they too will learn, it's not the Regulators, it's their choice of a deal, the choice not to buy quality brand names from reputable sources. There is too much E Bay buying and lots of junk with no recourse
If your playin around as a hobby its one thing but if you have to make your living at it day by day it's better to buy NEW Quality Brand Name stuff even if it costs an arm and a leg and not be playin repair man. Life is too short.
If your Regulators aren't working properly, first check that you aren't doing something wrong and then have the equipment checked by some one qualified. You may think you are but can you really see a minute pinhole in a diaphragm.
I have to get a chuckle out of seeing how many Migs are out there especially the low priced units that give the guy a Regulator instead of a Flowmeter and those guys move up to better machines but still run a Regulator, they just don't know better and no one is there to tell them.
I'm not here to wrag on anyone and if I say one thing that helps even one person, then I have done good, I hope.

Regulated to Death
Bambi