I cut my gas flow rate from 15 cubic feet per hour (CFH) to 3.75 CFH with no perceptible difference in arc or weld quality. I'm saving 75% on gas costs because I set myself free of the tombstone 'recommendation' of the welding manufacturers. Want to save $$$? - read on.
I looked at the operators' manuals for three typical MIG welders:
- Lincoln SP-125 Plus
- Millermatic 140, 140 Auto−Set, and 180
- Hobart Handler 187
Their 'recommended' gas flow rate is typically stated as:
- 15 – 20 cubic ft per hour (CFH) (7 – 10 I/min)
- use 20 – 25 CFH (10 – 12 I/min) when welding out of position or in a drafty locations.
If like me, you follow that 15 - 20 CFH 'recommendation' you will have good welds.
However, I found I could get the same good welds with 1/4 of those gas flow rates.
I have a Lincoln SP-175T.
I am particularly sensitive to gas usage because I use small 20oz CO2 tanks for portability.
A 20oz CO2 tank contains 10 cubic feet of CO2.
At a 'recommended' flow rate of 15 CFH, one tank in theory lasts me 40 minutes.
That is not very long.
In reality, I get rather less than this - maybe 25 - 30 minutes tops. Why?
With start/stop welding, like tacking for example, the pressure builds in the line behind the gas solenoid valve because the single stage regulator (used by 99% of us folks) only regulates well with continuous flow. When you click the trigger on, you can hear a burst of higher pressure/high flow gas out the nozzle - much louder than the sound of continuous (trigger pulled) gas flow rate.
Try it yourself.
Note: Release the tension on your wire feeder SO NO WIRE WILL STICK IN YOUR EAR!
Pull the trigger. You will hear a 'Poof' of gas followed by a 'whooshing' reduction until you reach a constant barely audible 'whooo' of continuous gas flow.
With such small gas tanks, I had an urgent need to economize on gas flow. In stages, I kept reducing the gas flow rate from 15 CFH until I reached 3.75 CFH - which is the limit that I can reasonable control with my regulator. Everything was just the same!
Note: You can tell you went too far - if it looks like you are welding with little or no shielding gas:
- arc quality reduces (sputtering)
- porosity appears in your weld
I'm certain to be target for many who will shout - Heresy!:nono:
You can't break one of the 10 Welding Commandments handed down from Mount Lincoln/Miller/Hobart.:gunsfirin
Do so at your peril!
The Tombstone Tablets say 15 - 20 CFH and that's that! Burn Him! :angry:
On the other hand... Want to save some money? :drinkup:
Try it yourself. Try reducing your gas flow rate and see what happens.
Maybe like me, you will discover you can weld just fine with far less that the 'recommended' flow rate.
Up to 75% saving can await the Courageous.
Rick V:waving:
I looked at the operators' manuals for three typical MIG welders:
- Lincoln SP-125 Plus
- Millermatic 140, 140 Auto−Set, and 180
- Hobart Handler 187
Their 'recommended' gas flow rate is typically stated as:
- 15 – 20 cubic ft per hour (CFH) (7 – 10 I/min)
- use 20 – 25 CFH (10 – 12 I/min) when welding out of position or in a drafty locations.
If like me, you follow that 15 - 20 CFH 'recommendation' you will have good welds.
However, I found I could get the same good welds with 1/4 of those gas flow rates.
I have a Lincoln SP-175T.
I am particularly sensitive to gas usage because I use small 20oz CO2 tanks for portability.
A 20oz CO2 tank contains 10 cubic feet of CO2.
At a 'recommended' flow rate of 15 CFH, one tank in theory lasts me 40 minutes.
That is not very long.
In reality, I get rather less than this - maybe 25 - 30 minutes tops. Why?
With start/stop welding, like tacking for example, the pressure builds in the line behind the gas solenoid valve because the single stage regulator (used by 99% of us folks) only regulates well with continuous flow. When you click the trigger on, you can hear a burst of higher pressure/high flow gas out the nozzle - much louder than the sound of continuous (trigger pulled) gas flow rate.
Try it yourself.
Note: Release the tension on your wire feeder SO NO WIRE WILL STICK IN YOUR EAR!
Pull the trigger. You will hear a 'Poof' of gas followed by a 'whooshing' reduction until you reach a constant barely audible 'whooo' of continuous gas flow.
With such small gas tanks, I had an urgent need to economize on gas flow. In stages, I kept reducing the gas flow rate from 15 CFH until I reached 3.75 CFH - which is the limit that I can reasonable control with my regulator. Everything was just the same!
Note: You can tell you went too far - if it looks like you are welding with little or no shielding gas:
- arc quality reduces (sputtering)
- porosity appears in your weld
I'm certain to be target for many who will shout - Heresy!:nono:
You can't break one of the 10 Welding Commandments handed down from Mount Lincoln/Miller/Hobart.:gunsfirin
Do so at your peril!
The Tombstone Tablets say 15 - 20 CFH and that's that! Burn Him! :angry:
On the other hand... Want to save some money? :drinkup:
Try it yourself. Try reducing your gas flow rate and see what happens.
Maybe like me, you will discover you can weld just fine with far less that the 'recommended' flow rate.
Up to 75% saving can await the Courageous.
Rick V:waving: