Announcement

Collapse
No announcement yet.

Critical Weld Inspection without Using Expensive Tools?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Critical Weld Inspection without Using Expensive Tools?

    I am just a hobbyist TIG welder, not a pro like you guys. So I dont have access to expensive tools to test welds. However, I am wondering if the welds I am doing are going to work in a critical situation. To understand let me twll you a bit about what I am doing:

    One of my hobbies is renovating and repairing old vintage travel trailers. Often these trailers have rust issues and you need to repair the chassis by slicing out some steel and welding new in. I prefer to slice out a whole cross member rather than splice in a new piece of metal. I am not sure how strong splicing in would be. The problem is much of the frames are square tubing. I can weld them just fine but cant inspect the back of the weld. At the same time the chassis is what takes most of the pressure from the trailer and they have some 25k to 40k of stuff riding on that chassis. So obviously I am concerned about weld quality.

    I TIG weld everything but I am self taught. I have been meaning to take a course but with working 50 hours a week as a software engineer, it has been hard to swing that. I feel fairly confident on things that aren't mission critical but the chassis trailer welds make me nervous. Right now I am using an old Syncrowave at a friend's business but I am about to buy my own Syncro 200, did the wiring for it this weekend and I am finishing fireproofing my garage shop.

    Any tips or tricks for inspecting welds when you cant see inside what you are welding? Also can anyone think of any tips for injecting argon into a square tube when the tube is welded at both ends? One end is easy, the other i worry about contamination of the weld.

    Thanks in advance.

    -- Robert

  • #2
    Take matters into your own hands. Learn how to test your own welds. Just like they do in school or on the job.



    Caution!
    These are "my" views based only on “my” experiences in “my” little bitty world.

    Comment


    • #3
      If you're not sure of the soundness of your work then why are you welding things that will travel down the road would be my question.
      It's all fun and games (or a neato hobby) till somebody gets killt.

      JTMcC.
      Some days you eat the bear. And some days the bear eats you.

      Comment


      • #4
        Can’t think of a better way for a rookie / beginner / hobbits / greenhorn / amateur to learn a good weld from a bad than a little DT.
        Just keep track of how the weld looked going in, when the coupon doesn’t break / shatter / split / rip / tear, or have any visible flaws then he / she is on right path.
        These rod and bar benders are cheap; just roll the coupon around the 1 1/2 inch die. Not as efficient as the professional hydraulic benders, but will ruin your day almost as fast!
        Caution!
        These are "my" views based only on “my” experiences in “my” little bitty world.

        Comment


        • #5
          I finally found it, (I’ve got to organize this computer)!

          Here is the AWS limited test plate, for those of you who don’t feel like welding up a 1 inch plate.

          Caution!
          These are "my" views based only on “my” experiences in “my” little bitty world.

          Comment


          • #6
            Learn what a face bend and a root bend is. Weld up some test pieces as Jesus has pointed out and bend the crap out of them.
            Miller Syncrowave 200 W/Radiator 1A & water cooled torch
            Millermatic 252 on the wish list
            Bridgeport Mill W/ 2 axis CNC control
            South bend lathe 10LX40
            K.O. Lee surface grinder 6X18
            Over 20 years as a Machinist Toolmaker
            A TWO CAR garage full of tools and a fridge full of beer
            Auto shades are for rookies
            www.KLStottlemyer.com

            Comment


            • #7
              Originally posted by kcstott View Post
              bend the crap out of them.
              But be gentle!
              Caution!
              These are "my" views based only on “my” experiences in “my” little bitty world.

              Comment


              • #8
                Any tips or tricks for inspecting welds when you cant see inside what you are welding? Also can anyone think of any tips for injecting argon into a square tube when the tube is welded at both ends? One end is easy, the other i worry about contamination of the weld.

                Thanks in advance.

                -- Robert[/QUOTE]

                Since you are welding on mild steel, there really is no need to purge the tubing

                Comment


                • #9
                  I worked in the lab at my last job, Just to check on myself, I made up three sets of the AWS Limited test plate. ( I used some 3/8 X 10 " CR )

                  The face bend coupon passed,No issues
                  The root bend coupon passed, No issues

                  I milled the next set of coupons into tensile test specimens. Both passed

                  I sent the other set out for Charpy testing at -20 and -40

                  The -20 failed ( Not horrible ) but still a failure

                  The -40 failed ( Big Time )

                  When I got the Charpy coupons back from the lab, I polished them and checked them under the microscope ( Etched, and un-etched )

                  Can you say Swiss cheese ? At least that's what they looked like @ 10,000X

                  The Charpy tests were just for my info, It wasn't my dime

                  I will try another set one day ( When I think I'm better )

                  Comment


                  • #10
                    Those RV trailer frames have really really crappy welds on them from the factory. It's shameful what bird poop passes as welding at those frame builders, especially one of the biggest names in RV chassis industry, named Lippert. They build frames for several big name RV manufacturers nationwide. Absolutely horrible quality comming out of their factory for years, amazing the frames manage to hold together at all.

                    Any weld you put on that trailer frame as an amatuer welder isn't likely to be any worse than the 'professional welds' that have been holding it together since it was new.
                    Millermatic350P/Python, MillermaticReach/Q300
                    Millermatic175
                    MillermaticPassport/Q300
                    HTP MIG200
                    PowCon 300SM, MK Cobramatic
                    ThermalArc 185ACDC, Dynaflux Tig'r, CK-20
                    DialarcHF, Radiator-1
                    Hypertherm PowerMax 380
                    Purox oxy/ace
                    Jackson EQC
                    -F350 CrewCab 4x4
                    -LoadNGo utility bed
                    -Bobcat 250NT
                    -PassportPlus/Q300
                    -XMT304/Optima/Spoolmatic15A
                    -Suitcase8RC/Q400
                    -Suitcase12RC/Q300
                    -Smith oxy/propane
                    -Jackson EQC

                    Comment


                    • #11
                      If you are maintaining a keyhole as you weld, then you can rest assured that the root has fused.

                      If you care enough to ask, you're already head and shoulders above the vast majority of people welding trailers.

                      80% of failures are from 20% of causes
                      Never compromise your principles today in the name of furthering them in the future.
                      "All I ever wanted was an honest week's pay for an honest day's work." -Sgt. Bilko
                      "We are generally better persuaded by reasons we discover ourselves than by those given to us by others." -Pascal
                      "Since we cannot know all that there is to be known about anything, we ought to know a little about everything." -Pascal

                      Comment


                      • #12
                        Originally posted by Desertrider33 View Post

                        Any weld you put on that trailer frame as an amatuer welder isn't likely to be any worse than the 'professional welds' that have been holding it together since it was new.

                        I couldn't disagree more. One reason being I'd never get away with setting my quality standards as "well it's bad but it's not as bad as that one over there".
                        But the main reason would be that the engineered design of the frame, likely made by semi skilled production welders, isn't going to contain spliced tube members. Like most automotive welds they'll be low stressed fillets or laps for the most part so they can get away with the poor looking work you typically see on a trailer or even a truck frame.

                        But the original poster (seems to me) to be asking about not replacing a full member and using those same low stress welds but instead splicing a tube into an existing tube to replaced damaged material.
                        If that's the case then he's entered an entirely different world where it's going to need either a full pen weld (either open butt v, or a groove with backing and backing is difficult when you're spooling in a tube splice) or a partial pen weld with additional reinforcing material attached.
                        All three of those alternatives are much more complex and much more heavily stressed than a simple fillet attaching a tube end to the frame.

                        The suggestions of using destructive testing on fillets and plates are fine in themselfs but won't tell the poor guy if he made a sound splice in a piece of tube.

                        So like I said, if he's nervous about his work he probably shouldn't be doing it on road going vehicles.
                        I've seen quite a few weld failures on trailers (other peoples work) and the best case puts the load in the ditch but I've seen them that resulted in fatal accidents involving children. No attempt to be a drama queen there but those things will make a forever impression on a welder.

                        Then of course maybe I missunderstood the post completely and he's really not spooling a tube in. It wouldn't be the first time.
                        My take.

                        JTMcC.
                        Some days you eat the bear. And some days the bear eats you.

                        Comment


                        • #13
                          Originally posted by JTMcC View Post
                          I couldn't disagree more. One reason being I'd never get away with setting my quality standards as "well it's bad but it's not as bad as that one over there".
                          But the main reason would be that the engineered design of the frame, likely made by semi skilled production welders, isn't going to contain spliced tube members. Like most automotive welds they'll be low stressed fillets or laps for the most part so they can get away with the poor looking work you typically see on a trailer or even a truck frame.

                          But the original poster (seems to me) to be asking about not replacing a full member and using those same low stress welds but instead splicing a tube into an existing tube to replaced damaged material.
                          If that's the case then he's entered an entirely different world where it's going to need either a full pen weld (either open butt v, or a groove with backing and backing is difficult when you're spooling in a tube splice) or a partial pen weld with additional reinforcing material attached.
                          All three of those alternatives are much more complex and much more heavily stressed than a simple fillet attaching a tube end to the frame.

                          The suggestions of using destructive testing on fillets and plates are fine in themselfs but won't tell the poor guy if he made a sound splice in a piece of tube.

                          So like I said, if he's nervous about his work he probably shouldn't be doing it on road going vehicles.
                          I've seen quite a few weld failures on trailers (other peoples work) and the best case puts the load in the ditch but I've seen them that resulted in fatal accidents involving children. No attempt to be a drama queen there but those things will make a forever impression on a welder.

                          Then of course maybe I missunderstood the post completely and he's really not spooling a tube in. It wouldn't be the first time.
                          My take.

                          JTMcC.
                          Sorry guys but I'm on JTMC's side on this one . If you are a hobbyist you should not be doing these types of welds. There is a lot of factors that go into splicing tube or frames. I don't think anyone on this forum would feel real good about giving a guy advice on something he is not qualified to do. Especially if that trailer he fix came unglued on the interstate and killed a family of 4 on their way to church!! Hate me if you want but you don't know me ! Jef

                          Comment


                          • #14
                            Originally posted by Wicked one View Post
                            Sorry guys but I'm on JTMC's side on this one . If you are a hobbyist you should not be doing these types of welds. There is a lot of factors that go into splicing tube or frames. I don't think anyone on this forum would feel real good about giving a guy advice on something he is not qualified to do. Especially if that trailer he fix came unglued on the interstate and killed a family of 4 on their way to church!! Hate me if you want but you don't know me ! Jef
                            Didn't we go over that on the welding of fork lift forks

                            And if a family of four is killed on their way to church didn't they just cut out the middle man
                            I'm ducking and running now
                            Miller Syncrowave 200 W/Radiator 1A & water cooled torch
                            Millermatic 252 on the wish list
                            Bridgeport Mill W/ 2 axis CNC control
                            South bend lathe 10LX40
                            K.O. Lee surface grinder 6X18
                            Over 20 years as a Machinist Toolmaker
                            A TWO CAR garage full of tools and a fridge full of beer
                            Auto shades are for rookies
                            www.KLStottlemyer.com

                            Comment


                            • #15
                              Originally posted by kcstott View Post
                              Didn't we go over that on the welding of fork lift forks

                              And if a family of four is killed on their way to church didn't they just cut out the middle man
                              I'm ducking and running now
                              Please define what you are saying. I do not understand.

                              Byron

                              Comment

                              Working...
                              X