Argon gauge

[steely dan]

A friend of mine borrowed my mig set and tipped the bottle over damaging the Argon pressure gauge . He replaced the regulator with a low cost modern unit that doesn't hold the bottle gas pressure when shut off . I tried to replace the gauge on my old but sturdy Wescol regulator but cannot find a source of NPT ( tapered ) 0-4500 psi ( 315 bar ) gauges.
I thought it was 1/4" npt but it looks like 1/2 " npt now I have a ruler against it.
Anyone know of a supplier for a suitable gauge ?

 

[daleyd]

Ebay possibly? If you don't mind spending a bit extra (but conversely you should get decent quality and the back up of a big company) RS components.

 

[chevy2]

Measured across the threads 1/4" npt thread is around a 1/2" wide thread,

Have to ask why theres ptfe tape around the thread where it goes into the bottle?,
Its not needed as it seals where the tapered part at the bottom seals at the base of the cylinder valve.

 

[hotrodder]

As Chevy, the seal between the reg and cylinder is made with the conical seat not the threads. Probably wrong but based on the PTFE tape i'd say it's just as likely you have a damaged cylinder seat as a problem with the modern/cheap reg. Speaking of which the days of servicing regulators are long gone, they have an 'expiry date' stamped into them thesedays and are supposed to be binned*. Cue debate about prehistoric regulators being better built than modern cheapies even if they're like triggers broom and have been rebuilt with cheapnese/random bits and not tested properly afterwoods etc...

As an aside it's not good practice to leave the regulator under pressure when not in use but that's another debate i'm not gonna get drawn into

* Yeah, it's kinda wasteful but if (and granted it's a fairly big if) there's an accident and a 300 bar cylinder takes out a wall or two the insurance assessor will presumably have a very smug look on their face if the remains of the regulator tell them it should've been replaced years ago

If you've leak tested the thing and it appears to be sealing but slowly leaks down when shut off under pressure then that's not uncommon. If it's definately the reg then throw it back your mate along with a Wescol (or Harris etc) catalogue and tell him to stop being cheap. That said if the cylinder seat is a bit manky (not uncommon) then it can sometimes take a few attempts to get the thing to seal even with the best regulator in the world. That problem is never gonna go away unless people stop doing the things up like they're cylinder head bolts and then adding gobs of PTFE tape when it leaks [/daily mail]

 

[steely dan]

Bottle gas valve shut with Wescol trapped pressure takes three days to leak off . Bottle gas valve shut on cheap replacement trapped pressure takes 3 to 4 hours to leak off. Cheap regulator does the job and the quantity of gas in question is min and can't be saved anyway , I'd just like to have the Wescol up and running again .
I appreciate comments on PTFE etc etc and the main seal between bottle and either regulator has been tested and is sealing and not under suspicion . Bourdon tubes in each serviceable gauge are ok and gauges tested on a dead weight tester and are within calibration.
I've tried Ebay both UK and DE and spoken to several Instrument suppliers but all so far are parallel thread gauges .
As I asked does anyone know where I can purchase a 1/4 npt gauge of suitable range ?

 

[Tman]

Bottle gas valve shut with Wescol trapped pressure takes three days to leak off . Bottle gas valve shut on cheap replacement trapped pressure takes 3 to 4 hours to leak off. Cheap regulator does the job and the quantity of gas in question is min and can't be saved anyway , I'd just like to have the Wescol up and running again .
I appreciate comments on PTFE etc etc and the main seal between bottle and either regulator has been tested and is sealing and not under suspicion . Bourdon tubes in each serviceable gauge are ok and gauges tested on a dead weight tester and are within calibration.
I've tried Ebay both UK and DE and spoken to several Instrument suppliers but all so far are parallel thread gauges .
As I asked does anyone know where I can purchase a 1/4 npt gauge of suitable range ?

Check eBay for old argon or oxygen regulators

 

[daleyd]

A gauge with different fitting and an adaptor?

 

[backpurge]

Seeing as replacing gauges is in direct opposition to BCGA and therefore HSE guidelines you may struggle to get hold of suitable replacements

 

[MarkG]

You'll be lucky to find anyone that will sell a single gauge nowadays.. As backpurge mentioned above, it is now against BCGA & HSE regulations.

Back in the day when you could do service exchange, it wasn't an issue, but when you can pick up a decent quality regulator for under £50 now, it's hardly worth the hassle.

 

[gulf]

Single gauges are available.I saw some for sale recently..but where?.Ill send you the link when i find it.Im yet to see anything more dramatic than a loud pop and loss of gas when an argon regulator blows.Acey/propane regulators are a different kettle of fish if they blow for obvious reasons

 

[backpurge]

Single gauges are available.I saw some for sale recently..but where?.Ill send you the link when i find it.Im yet to see anything more dramatic than a loud pop and loss of gas when an argon regulator blows.Acey/propane regulators are a different kettle of fish if they blow for obvious reasons

And if that loss of gas is in a confined space you've got a room full of a gas you can't see, smell or touch that will kill you

 

[gulf]

And if that loss of gas is in a confined space you've got a room full of a gas you can't see, smell or touch that will kill you

You dont say??? :O

 

[backpurge]

You dont say??? :O

Not too sure I understand where you are coming from here

 

[gulf]

lol

 

[backpurge]

Eh!!!!!!!!!!

 

[Tman]

Just wondering how many of you out there are using regs out of date for home use ? don't think av changed my regs in the garage yet must be from the late 70's safire 3 stage 2 all of them never missed a beat just goes to show how long they can last. Hse gone mad. Have to change them for business use tho because insurance would use any think to invalidate a policy.

 

[brightspark]

Just wondering how many of you out there are using regs out of date for home use ? don't think av changed my regs in the garage yet must be from the late 70's safire 3 stage 2 all of them never missed a beat just goes to show how long they can last. Hse gone mad. Have to change them for business use tho because insurance would use any think to invalidate a policy.

mine on my oxy acet gear are over 30 years old . i have a few sets but why should i change them when they work perfectly . mine get used maybee 25 times a year not every day as in industry or comercial use eg 363 days a year for 5 years

 

[Jan]

Single gauges are available on eBay. The cheaper ones will be coming from the Far/Near East and quality should be taken with a pinch of salt. However I had a similar mishap with my cylinder when my new welding trolly's base bent a bit (since reinforced so it can't happen again). Although the full gauge setup is good to 300 BAR, the new contents gauge is only good to 250 BAR. However since the BOC Argoshield Lite cylinders are only filled to 230 BAR that shouldn't be a problem. Even before adding this new gauge I have always slowly cracked off the valve to prevent a sudden shock to the gauges.