New to MIG welding - Gas cylinder?

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This is for newbies like me that are setting up their MIGs for Gas the 1st time.I bought a Thoroughbred #1 cylinder (exchange program) from my local Tractor Supply Co. to use with my Northern Industrial MIG 135.I originally set it up to use the flux core .030 wire as this was the simplest way to get started. After playing around on thicker metals I wanted to start to do some patch panels on my car - 22 gauge mild steel.The flux core was too hot and burned through on the thinner test metal as I knew it probably would by reading the threads on this forum.This past weekend was nice weather wise so I decided to do the switch over to .023 solid wire and gas C25. Everything was going just fine - I switched the polarity back to + gun & - ground changed the roller wheel to .024 threaded the wire changed the tip and nozzle, connected the gas line to the welder, connected the gas line to the regulator and connected the regulator to the gas cylinder.Here comes the newbie part - turned the gas cylinder wheel in the ON direction and it only moved a 1/4 inch then stopped. OK now what? Is that it? So I started to turn the regulator knob to get a reading of 20cfm on the dial and NOTHING.Did I just buy an empty cylinder? No way I mean I have bad luck and stuff but that couldn't be. I turned the cylinder valve in the closed direction, turned the regulator knob back to where it spun free and unhooked the regulator. Powered up my little air compressor and tested the regulator - cool it registered air movement so I knew that was good.I hooked everything back up and tried again only this time giving the gas cylinder valve a stronger twist - still it only moved 1/4. Now being new to all this I didn't want to break anything especially a high pressure gas cylinder. So I turned everything off and unhooked it.I called 1-877-GAS-PONY the Thoroughbred gas cylinder company and asked my newbie question. "How far should the gas cylinder valve turn before I see numbers register on my regulator?" The techs answer was "a good full turn or two".My next question was "OK if that's the case mine only turned a 1/4 of an inch - how hard do I need to turn the valve as I don't want to break anything?" The techs answer was "sometimes you really got to muscle the values to get them to turn" and that my friends in the answer to my question.Northern Industrial MIG 135
Reply:When you hook up a fresh cylinder, you should crack the valve open to blow out any dust and loose particles before you attach your regulator. That will give you a good indication as to the cylinders contents. Just make sure that you stand on the opposite side of the valve so as not to get a blast in the face.The valve on your cylinder will be double seated, and should be completely open when in use, and completely closed when not. This reduces the chances of leaking by the seats.
Reply:Originally Posted by Pro-FabWhen you hook up a fresh cylinder, you should crack the valve open to blow out any dust and loose particles before you attach your regulator. That will give you a good indication as to the cylinders contents. Just make sure that you stand on the opposite side of the valve so as not to get a blast in the face.The valve on your cylinder will be double seated, and should be completely open when in use, and completely closed when not. This reduces the chances of leaking by the seats.
Reply:I've had bad valves in the past that wouldn't open well. On a very rare occasion I've even gotten an empty or 1/2 ful cylinder as well. Usually the valve didn't seal well and the gas just leaked out before I got it. Never had any issues with my LWS. I give them a call, explain the issue, if I can't get right back, or simply talk to the counter guy when I get back, and they swap me a new cylinder at no charge..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:with the double seated valves they sometimes get very wedged internally and it will take all you got to crack it loose the first time, so have at it.
Reply:Perfect, thanks for the reassurance. I do have a follow up ?. Should I use plumbers teflon tape on the threads or not?I am leaning towards yes but don't know if there would be a reason not to.Northern Industrial MIG 135
Reply:DEFINITELY NOT!!!Just assemble dry. If you have leaks, then replace your hose end fitting.You do not want to add anything to the brass threads that could get into your regulator. Pipe dope included.
Reply:Originally Posted by Pro-FabDEFINITELY NOT!!!Just assemble dry. If you have leaks, then replace your hose end fitting.You do not want to add anything to the brass threads that could get into your regulator. Pipe dope included.
Reply:Originally Posted by baflinnGood point about the dust and stuff - instead of cracking the valve though I think I'll use my air gun to give the connection a thorough blast. Save me some precious gas since I'm only a hobbyist and didn't buy a big cylinder, but good point none the less. - Thanks.
Reply:Originally Posted by WeldingMachineFYI: Don't ever crack the valve without proper ventilation.  Rapid asphyxiation is RAPID!Also, never use compressed air to blow them out.  Oil & water should never go near a regulator, & compressors piss out both..
Reply:Update: tank (size #1 - 20cf) has been hooked up (dry connections) and was able to get good pressure so I will be using it this weekend with the NI Mig 135 to do some patch panel work on the '74 Pinto.I'm gonna keep a clock on the gas usage to see how long the small tank lasts and will report back here as I go.Northern Industrial MIG 135