No announcement yet.

Gas Flow

  • Filter
  • Time
  • Show
Clear All
new posts

  • Gas Flow

    With tig welding what happens when welding thin Ga. sheet metal (16 ga S/S) and the gas flow is to high? Also just the opposite of that if the flow is to low. What kind of an appearance on my bead will tell me that the flow is incorrect? I see that for the above material some say 15Cfh and some say 20 cfh. I would think more is better than less. Thanks.
    Last edited by redmule1154; 01-16-2011, 07:02 AM.

  • #2
    gas flow

    Thin material will require a backing gas or tape. This will prevent a sugaring or porosity, ruining any strength in the weld. However, up to 40 lbs gas out of the tig torch will only protect your weld better from oxidation.
    On a side note, keep moving. Experience will tell you if your travel rate is appropriate. Look to see a pink or blue to the metal that wipes off easily. Any black is an indicator. Good luck


    • #3

      sorry, the 40 lbs should says Cfh as you noted


      • #4
        More is not always better. Too small a nozzle, with too much gas will cause a venturi effect at the orifice of the nozzle. Aside from just wasting gas, you risk pulling air into the gas stream.

        Any more than 20 cfh is too much imo for 16 ga.

        Any less than 5 chf is too little imo.

        Gas lenses always save money.
        Nothing welded, Nothing gained

        Miller Dynasty700DX
        3 ea. Miller Dynasty350DX
        Miller Dynasty200DX
        ThermalArc 400 GTSW
        MillerMatic200 with spoolgun
        Lincoln SP-170T
        Linde UCC305 (sold 2011)
        Hypertherm 1250
        Hypertherm 800
        PlasmaCam CNC cutter
        Fadal Toolroom CNC Mill
        SiberHegner CNC Mill
        2 ea. Bridgeport
        LeBlond 15" Lathe
        Haberle 18" Cold Saw
        Doringer 14" Cold Saw
        6 foot x 12 foot Mojave granite


        • #5
          Rule of thumb - 1cfh per 10A outout although I rarely go below 10cfh regardless.
          MM200 w/spot controller and Spoolmatic 1
          Syncrowave 180 SD
          Bobcat 225G Plus LPG/NG w/14-pin*
          *Homemade Suitcase Wire Feeder
          *WC-1S & Spoolmatic 1
          PakMaster 100XL
          Marquette "Star Jet" 21-110