Shooting the gap questions.
RSS | Subscribe | Contact Us | Advertise | About Us
Results 1 to 14 of 14
  1. #1
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Shooting the gap questions.

    Have any of the members here ever done this type of Tig welding? If my grandson gets into the welding apprenticeship at the local Trident Submarine Base, I’m sure he will have to learn to do this type of welding.
    I would like to know the size of the gap? Size of the filler rod? Degree of bevel? Looks like in this video they use a knife edge. I’ve played with this technique, but my eye sight is not good enough, especially now that I have to use reading glasses to weld with.
    Thanks so much for your help!
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  2. #2
    Join Date
    Oct 2007
    Location
    Vandalia, Ohio near Dayton
    Posts
    2,483

    Re: Shooting the gap questions.

    Knife edge land. Can be done with up to 1/16" land, in most cases.
    3/32" filler rod
    3/32"- root opening at the start. Wider at the finish as the joint's going to pull shut as the root goes in.
    37.5° bevel angle 75° included angle

    I've never seen anyone use a foot pedal in the field. But for some alloys I could see the advantage of having one and being able to manually pulse the weld current. fingertip wheel control might be useful if you have enough cable to make it work.

    Backfeeding the rod was never something I was good at. But could do it if the situation required. It looks easier on the hands and wrists, rather than imitating a contortionist to get the rod in position for welding the bottom of the joint. But the tension of doing it always was more stressful than using the traditional methods I was taught.

    Making the fitup work was always a PITA. Seems like the work I saw in the field never had the ideal root opening for making this work and grinding to get the right fit was never practical.
    Benson's Mobile Welding at your worksite or place of business. Serving Dayton, Ohio and the surrounding metro areas.
    AWS Certified Welding Inspector (#XXX10731) and Certified Welding Educator (#XXX1008E)

  3. #3
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Re: Shooting the gap questions.

    A DAB will do, thank you very much for the fit up advice! The pipe is already beveled at 37.5 degrees. I’ll see how he does on this, tomorrow morning!
    Thanks again!
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  4. #4
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Re: Shooting the gap questions.

    Got the pipes all fit up. I’ll wait until tomorrow morning when the grandson gets here to tack the pipes.
    Attached Images Attached Images    
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  5. #5
    Join Date
    Apr 2015
    Location
    Fredericksburg, VA
    Posts
    1,223

    Re: Shooting the gap questions.

    I have not seen TheBFA post in a while but maybe send him a PM to see if you can reach him and see if he has any thoughts.

    Sent from my SM-G930V using Tapatalk
    Millermatic 252 MIG
    Miller Dynasty 200DX TIG
    Miller Spectrum 375 Plasma
    Altas 12x36 Metal Lathe
    Bridgeport Milling Machine
    www.psacustomcreations.com

  6. #6
    Join Date
    Mar 2017
    Location
    bar stool
    Posts
    1,621

    Re: Shooting the gap questions.

    Just a quick question Gramps.

    Unless you got an ironclad guarantee this kid can keep his mouth shut when he meets with the Apprenticeship Coordinator, are you sure teaching him this process is a good idea?

    Most coordinators I know look at a kid coming in the door with established skills as a deduction on the score card. They want the instructors to teach the skill their way, without having to break what they consider previously learned bad habits.
    I understand what you're trying to accomplish, but I gotta say too much skill might be bad at this point. Once he's in the story changes a little.

  7. #7
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Re: Shooting the gap questions.

    The welding supervisor at the Trident Submarine Base wanted a list of welders, and what the grandson is working on. My son-n-law told the welding supervisor that I use to drive piling on the water. Building bridges, ferry docks, and container ship docks. According to my son-n-law the welding supervisor was very impressed with the welders, and what the grandson has done so far. Only time will tell if the grandson gets into the welding apprenticeship.
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  8. #8
    Join Date
    Aug 2004
    Location
    North Central Indiana
    Posts
    4,072

    Re: Shooting the gap questions.

    CEP where did you get that alignment tool and what does one like it cost, that's a super neat gadget. I use to use 4 1/4 X 2 plastic welding plate covers to set my gap.

  9. #9
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Re: Shooting the gap questions.

    I’ve had it for years. I think I bought it from Pipefitter.com. The one I have is for 4” to 6”. All they have listed now is for 2” to 4”.
    https://pipefitter.com/store/tools/pipe-clamps/
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  10. #10
    Join Date
    Mar 2012
    Location
    Australia
    Posts
    464

    Re: Shooting the gap questions.

    Hey CEP, this is something I have a fair bit of experience with, both on stainless and carbon.

    I like it like this.

    -5/32 gap, allows for the gap the shrink while welding, if your eyeing the gap your probably also backfeeding so you have to allow for it to pull up a bit, if I have the backfeed a stainless joint I sometimes even go for a 1/4 inch gap to make sure I still have 3/32 left once it get 3/4's around
    -3/32 wire
    -no land
    -30 degree bevel, steeper prep make things a bit more forgiving and move a bit slower, I bump the amps up a touch as well, with the wire going in the wrong way it's easier to get some un melted stab in's especially with ER70s-2 or stainless, so a bit more heat helps with that.

    gotta have solid feeding technique.

    but with that said, welding with a small land is no problem, I often knife out a prep to widen it up a bit if I have to eye the gap and backfeed.

    here's me backfeeding, eyeing the gap and welding downhill all in one on stainless on a job earlier this year.



    if the boys never done it before, first get him to practice with having alot of wire poking out of the feed hand, thats whats seems to catch out most is not being able to control the wire through the prep, the wire tends to want to stick to the pipe more then feeding from the outside as there's less heat and then people panic, when it does stick just get him used to bring the heat to where the wires stuck to melt it off and continue.
    Last edited by ttoks; 11-08-2018 at 04:01 AM.

  11. #11
    Join Date
    Nov 2012
    Location
    South Texas
    Posts
    2,291

    Re: Shooting the gap questions.

    The bigger the gap, the better you can see. Also don't have to worry so much about the wire getting stuck. I would use a 3/16 gap and a 1/8 wire. Everything else standard.

  12. #12
    Join Date
    May 2010
    Location
    Port Orchard, WA.
    Posts
    10,025

    Re: Shooting the gap questions.

    Grandson didn’t have much luck with shooting the gap yesterday. This is going to take some time for him to learn! I’m not a lot of help with this either. Friday he has an interview with the welding supervisor of the welding department at the Trident Submarine Base.
    Thanks so much for the advice ttoks, and TimmyTIG!
    I found this video on You Tube.
    Don’t pay any attention to me
    I’m just a hobbyist!

    Carl

    Dynasty 300
    V350-Pro w/pulse
    SG Spool gun
    1937 IdealArc-300
    PowerArc 200ST
    3 SA-200s
    Vantage 400





  13. #13
    Join Date
    Dec 2009
    Location
    Stevens Point, WI
    Posts
    4,412

    Re: Shooting the gap questions.

    Must be big money in pipes that everyone chases them.
    12v battery, jumper cables, and a 6013.
    I only have a facebook page. https://www.facebook.com/pages/VPT/244788508917829

  14. #14
    Join Date
    May 2008
    Location
    Orange, TX
    Posts
    17,037

    Re: Shooting the gap questions.

    Travis (fieldres) has a number of looking thru the gap videos on his youtube channel.
    MM200 w/Spoolmatic 1
    Syncrowave 180SD
    Bobcat 225G Plus - LP/NG
    MUTT Suitcase Wirefeeder
    WC-1S/Spoolmatic 1
    HF-251D-1
    PakMaster 100XL
    '68 Red Face Code #6633 project
    Star Jet 21-110

    Save Second Base!

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