Looking for tips, tricks, and advice in GMAW, GTAW, SMAW
RSS | Subscribe | Contact Us | Advertise | About Us
Results 1 to 22 of 22
  1. #1
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Currently i am working on my GTAW. I have been working on a standard T-Joint. I just cant seem to efficiently work the puddle. Im using 3/8" steel cleaned. I have been setting my machine around 85-90. My gas flow is at 25. Using the walk the cup technique. Ive been stuck on this weld for over a week and would like to move on to the next one. Any tips anyone could offer to help me out.

    I am also working on getting better in the other two processes. If there are any knowledge that i should know before headed down a path toward working on pipelines from a weld stand point. Any welds that anyone suggest i should try running. My class is pretty well equip for me to try a variety of welds. Our machines are newer Lincolns. We have some pipe but its thin. I dont know the specific thickness because we have never used it with in the two years i have been in the class. I am willing to learn anything that could help me, or just things that i should know. Any help is much appreciated.

  2. #2
    Join Date
    Jun 2012
    Location
    CT
    Posts
    3,172

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    90 amps on 3/8ths steel? way too low. You should be in the 140-170 range for sure. Maybe more. I don't subscribe to the 1 amp per thousandths of thickness rule, much above gauge metal thicknesses, so I am not going to tell you that you need a crazy amount of amps. But for sure you need more. You will likely need a larger tungsten too. Are you currently using a 1/16th tungsten? (just a guess)

    Have you mastered stick yet? I think it is a bad idea to start on TIG or MIG before you get half way decent on stick. It is a foundational skill.
    Millermatic 252
    Syncrowave 250
    Purox Metalmaster

  3. #3
    Join Date
    Jun 2012
    Location
    Bemidji MN
    Posts
    13,620

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Yep, what Louie said

    Personal preference for heavy material like that is 200-225 amps or so, with 3/32" or 1/8" filler.

    250 amps works pretty good with 1/8" filler.

    It's not a "need" though - I just like to go fast and use a lot of power
    Dave J.

    Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

    Airco 300 - Syncro 350
    Invertec v250-s
    Thermal Arc 161 and 300
    MM210
    Dialarc
    Tried being normal once, didn't take....I think it was a Tuesday.

  4. #4
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Quote Originally Posted by Louie1961 View Post
    90 amps on 3/8ths steel? way too low. You should be in the 140-170 range for sure. Maybe more. I don't subscribe to the 1 amp per thousandths of thickness rule, much above gauge metal thicknesses, so I am not going to tell you that you need a crazy amount of amps. But for sure you need more. You will likely need a larger tungsten too. Are you currently using a 1/16th tungsten? (just a guess)

    Have you mastered stick yet? I think it is a bad idea to start on TIG or MIG before you get half way decent on stick. It is a foundational skill.
    Yes I have master stick. And my welding inspector told me when I finish one pass at 90 it was too hot. Yes 1/16 on the tungsten

    Sent from my LG-M150 using Tapatalk

  5. #5
    Join Date
    Mar 2012
    Location
    Australia
    Posts
    464

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    How hot is to hit according to your instructor?

    A guy on here did some testing a while ago welding lap joints on stainless to highlight heat input, did three, one at around 80 amps, one at 120ish and one at 160 ISH, the 160 amp run had the least heat input as it melted the weld pool and got moving, the 80 amps run ended with the entire coupon turning purple from heat soak.

    I'd be running 180-250 amps with a 1/8 tungsten

    Sent from my R7sf using Tapatalk

  6. #6
    Join Date
    Jun 2012
    Location
    CT
    Posts
    3,172

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Yes I have master stick.
    Great...good news

    And my welding inspector told me when I finish one pass at 90 it was too hot.
    That may be because the amps are too low. It doesn't make sense at first, but having your amps too low causes you to slow way down on travel speed. Heat input is a function of more than just amps. It includes travel speed and weld time as well. There is a formula that I can't remember, but trust me more amps will increase your travel speed and lower your heat input.

    Yes 1/16 on the tungsten
    You will need a larger tungsten. 1/16th is only good up to about 100 amps. 3/32 ought to do you right for this. It will be good up to about 200 amps.
    Millermatic 252
    Syncrowave 250
    Purox Metalmaster

  7. #7
    Join Date
    Jun 2012
    Location
    CT
    Posts
    3,172

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    I am assuming you aren't welding anything with a knife edge bevel? that might be the only case worth using 90 amps.
    Millermatic 252
    Syncrowave 250
    Purox Metalmaster

  8. #8
    Join Date
    Dec 2013
    Location
    Mount Tabor VT
    Posts
    5,084

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    I run a bulldozer sometimes. A bulldozer has a decelerator. I believe this would be a welding tool more useful than an accelerator on a TIG welder. It seems more intuitive. step on it when you feel you are going too fast. Otherwise, set the welder as high as you hope to go.

    There is a point where there is such a thing as too hot, but usually travel speed can control that. More amps, moving faster may be tough for beginners, but will become easier. Try on scrap. Only the actual puddle needs to be hot. Moving faster prevents heat from dissipating as far.
    An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.

  9. #9
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Quote Originally Posted by Louie1961 View Post
    Great...good news



    That may be because the amps are too low. It doesn't make sense at first, but having your amps too low causes you to slow way down on travel speed. Heat input is a function of more than just amps. It includes travel speed and weld time as well. There is a formula that I can't remember, but trust me more amps will increase your travel speed and lower your heat input.



    You will need a larger tungsten. 1/16th is only good up to about 100 amps. 3/32 ought to do you right for this. It will be good up to about 200 amps.
    Ok. Let me try and see if i have my head wrapped around what everyone is saying. Is tig suppose to have roughly the same travel speed that you would get out of mig and stick. Having the higher amps is allowing you to move across the joint effectively welding it together, but because you are moving at a decent pace you are not having as much of the heat transfer as you would if the amps were low forcing you to slow way down to manipulate the puddle. If im at all headed in the right direction with that i would say the reason for the lower amp suggestion would be to allow us to learn the technique. If thats the case i have a feeling tig is about to get a bit easier for me.

    Oh i am also not quite sure if we have another sized tungsten. I know we have a good range in filler size but im not sure about tungsten
    Last edited by Daryllonewolf18; 11-09-2018 at 04:58 PM.

  10. #10
    Join Date
    Jun 2012
    Location
    CT
    Posts
    3,172

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Jody does a much better job than I can...watch this

    Millermatic 252
    Syncrowave 250
    Purox Metalmaster

  11. #11
    Join Date
    Dec 2013
    Location
    Mount Tabor VT
    Posts
    5,084

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    You can't function without 3/32 tungsten. If your welder is powerful, you need 1/8. You can make do with too big a tungsten. I have all sizes. most of the time, I use 3/32".

    I'd say no TIG weld is ever as fast as MIG, but too slow is a bigger concern than too fast. I strive for WET. I want every weld to flow, making a liquid bond with the piece I'm trying to weld. A wet weld is better looking, and stronger. The puddle has to be hot enough to be a true liquid, and it needs a bit of extra BTUs to melt a bit of the metal you hope to join. When both the filler, and a bit of the workpiece are liquid, and enough heat is present to make turbulence at that surface where work, and filler meet. some mixing happens. That is your Holy Grail, For that 1/16" you have done your job, Move another 1/16", repeat.

    When you place two pieces of metal together at differing temperatures some heat transfer occurs. At the instant they join molecularly, heat transfer increases sharply. A dry weld, that doesn't effectively join them limits heat transfer. They might not both be hot enough. A good wet weld improves heat transfer, making the next dime form easily.
    An optimist is usually wrong, and when the unexpected happens is unprepared. A pessimist is usually right, when wrong, is delighted, and well prepared.

  12. #12
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    That video was really helpful. Ill need to practice a bit with the filler but adding the speed to my equation solves a lot of problems. At least in my head.

  13. #13
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    I will have to try the WET concept as well.

  14. #14
    Join Date
    Apr 2008
    Location
    NW ON Canada
    Posts
    3,029

    Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    With the equipment I have, I wouldn't waste my time welding 3/8" thick steel with tig. It's just too slow.
    3/8" mild steel is SMAW territory, 1/8 7018 at 125 amps or 5/32 7018 at 150-160 amps.
    Last edited by snoeproe; 11-09-2018 at 06:42 PM.
    Jason
    Lincoln Idealarc 250 stick/tig
    Thermal Dynamics Cutmaster 52
    Miller Bobcat 250
    Torchmate CNC table
    Thermal Arc Hefty 2
    Ironworkers Local 720

  15. #15
    Join Date
    Jun 2012
    Location
    CT
    Posts
    3,172

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Or gas shielded flux core...
    Millermatic 252
    Syncrowave 250
    Purox Metalmaster

  16. #16
    Join Date
    Nov 2012
    Location
    South Texas
    Posts
    2,291

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    I set my machine on 285 when I'm welding carbon with TIG. Any higher than that tends to blow out a chunk of base metal on startup. I always want to be on the razor edge of too hot, welding cold is asking for trouble.

  17. #17
    Join Date
    Jun 2012
    Location
    Bemidji MN
    Posts
    13,620

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Quote Originally Posted by TimmyTIG View Post
    I set my machine on 285 when I'm welding carbon with TIG. Any higher than that tends to blow out a chunk of base metal on startup. I always want to be on the razor edge of too hot, welding cold is asking for trouble.
    285 amps....I like how you roll

    I'll have to try that now too. I've not gone past 250 so far.
    Dave J.

    Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

    Airco 300 - Syncro 350
    Invertec v250-s
    Thermal Arc 161 and 300
    MM210
    Dialarc
    Tried being normal once, didn't take....I think it was a Tuesday.

  18. #18
    Join Date
    Dec 2010
    Location
    SoCal-LA
    Posts
    8,728

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Do you have remote contactor and current control? And who told you to walk the cup ? Your torch angle may be all wrong.
    Weld like a "WELDOR", not a wel-"DERR"
    MillerDynasty700DX,Dynasty350DX3ea,Dynasty200DX,Th ermalArc400GTSW,LincolnSW2002ea., MillerMatic350P,MillerMatic200withspoolgun,MKCobra Mig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig3ea.

  19. #19
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Quote Originally Posted by shovelon View Post
    Do you have remote contractor and current control? And who told you to walk the cup ? Your torch angle may be all wrong.
    My high school has a welding program. My instructor is a CWI. Im a second year in the program. Ill graduate with A mig certification and a stick certification. I am currently OSHA safety certified. I will also have about 7 qualifications. The walk-the-cup is the method he wants us to use for the t joint.


    Name:  Snapchat-183589267.jpg
Views: 105
Size:  53.2 KB


    This was my last weld. at 90 amps. i believe i was using 3/8 filler.

  20. #20
    Join Date
    Mar 2012
    Location
    Australia
    Posts
    464

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Quote Originally Posted by Daryllonewolf18 View Post
    My high school has a welding program. My instructor is a CWI. Im a second year in the program. Ill graduate with A mig certification and a stick certification. I am currently OSHA safety certified. I will also have about 7 qualifications. The walk-the-cup is the method he wants us to use for the t joint.


    Name:  Snapchat-183589267.jpg
Views: 105
Size:  53.2 KB


    This was my last weld. at 90 amps. i believe i was using 3/8 filler.
    90 amps is far to cold for that joint, perhaps if it was super duplex stainless you might weld that cold, but all youre doing is heat soak the parts and getting quite a rough finish.

    also 3/8th filler? you dont mean 3/32 do you?

  21. #21
    Join Date
    Nov 2018
    Location
    Indiana
    Posts
    23

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Yes typo. i meant 3/32. and ok ill turn up the amps

  22. #22
    Join Date
    Nov 2012
    Location
    South Texas
    Posts
    2,291

    Re: Looking for tips, tricks, and advice in GMAW, GTAW, SMAW

    Just because he's a CWI doesn't mean he knows how to weld.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
RSS | Home | Penton Media | Contact Us | Subscribe | For Advertisers | Terms of Use | Privacy Statement