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  • #16
    Originally posted by Noel View Post
    dvice...Thank you for the detailed reply. I down loaded the picture and enlarged it. I think it's weldable and fixable. My opinion.
    I also think your getting it to hot and liquid. Like adding excess liquid in the mash potato's. Smooth and creamy lacking texture.
    While I did notice some porosity from contamination, I'm of the opinion it's the result of excessive puddle fluidity and resulting metallurgical structure being weaker that with cooling and contraction forces, causes it to crack.

    It could be due to arc length, higher currents, power source setting adjustments, as well contraction from the other side if that make sense? This again is my opinion.

    I would weld small beads, less heat, tighter arc and maybe tweak the balance slightly, above all, take your time. The magic will happen fast or slow... Your rapidly boiling the potato's and you'd be better off if they simmered instead, if that makes any sense?

    I don't see the powder burns of excessive zinc in the aluminum. I do however see a need for finer control of depositing metal. My advice, slow down, smaller deposits more frequently to rebuild it. Three or four small passes instead of one or two larger passes. Finer grain structure, stronger tougher deposits.

    You might also add a light preheat to the back side to reduce contraction stresses before and possibly after. Just a thought and hopefully of some benefit?
    yeah initially the crack would seperate as the edges puddled!!.. and if i didnt get a drop on filler that contacted both sides of the split... the split just grew badly! i dont have the depth of material.....i tried slow at first and it was a bear to get a puddle that lasted....long enough to get the rod in there and not hit the tungsten... maybe if i had .040 filler material.... most times for me good welds only happen when you have a steady firm place to control your hand and thus the torch. it seems to me th recievers alloy welds fine to my filler material AND THE 6061... its just tough to weld with the thick thin sections and the steel underneath possibly supplying contaminates......i just dont know what it cracks EVERY TIME

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    • #17
      "
      yeah initially the crack would separate as the edges puddled!!."

      I know this is as hard to type an explanation as it is to explain it, but the oxide layer and voltage forces play a role in what you see happening. As easy as it is to arm chair answers, a number of issues as I've mentioned are at play, which have to be taken into account.

      "if i didnt get a drop on filler that contacted both sides of the split... the split just grew badly!"

      Ever watch beavers build a ****? Same principle applies. Start on one side. Add more to one side. Keep adding more until you reach the other side. Then tie them together. Or, you could try as your doing, dropping a tall tree across and hope it fill the gap?

      "i tried slow at first and it was a bear to get a puddle that lasted....long enough to get the rod in there and not hit the tungsten..."

      Parameters. Tungsten size and profile. Arc length voltage forces and heat input. Torch angle inclination, using a gas lens, also current flow +/- values.

      "maybe if i had .040 filler material..."

      While 1/16" is a pretty small wire, you could unroll from a spool of GMAW and straighten it, it will be the same.

      "most times for me good welds only happen when you have a steady firm place to control your hand and thus the torch. "

      Works better for me to. But the goal is to remember, aim for the target, don't count on a ricochet. Understand how a tilt of the torch changes where you point, and the heat goes/changes focus. How shaking or up and down variations changes things. Tilt your head not the torch.

      "
      its just tough to weld with the thick thin sections and the steel underneath possibly supplying contaminates"

      A dog chasing a tail does catch it if it slows down. Time to regroup. Grab some scrap and run a few beads. Try to weld "smaller". Keep the bead narrow and taller. Think beaver.

      "
      i just dont know what it cracks EVERY TIME"

      I gave my best guesses.
      https://www.youtube.com/watch?v=K3NTAuDjuYA

      Notice the beads at 2:30.
      As I mentioned, lots is going on. Up to you to figure it out but buddies commentary may help that and with video, a lot less typing to explain it all.

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      • #18
        Well certain alloys you just can not weld period. If it is one of those like 7075, sorry but no you can NOT weld it. Doesn't matter how good you are or what you try to do its just not going to happen. And sometimes the weld will look good but it will crack later on. Can be days later if I recall.
        www.silvercreekwelding.com

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        • #19
          I agree. I don't think it's a weldable alloy. I've done tons a ugly welds on aluminum to get out of a bind and as long as you see the filler and the base metal come together, you generally have a sound weld, just ugly. Being that it happens every single time, it's not likely chance.

          That's too bad benelli wouldn't do anything about that. I had a cracked frame on a para ordnance (this was years ago before "the freedom group" gobble them up...) that had three cracks. I was the third owner of the pistol and it was probably 10 years or older when I got it. I called them up, sent it to them, they replaced it for free. I even told them I was the third owner. I still have it and run it a good bit. Probably one of the best running 1911s in my armory.

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          • #20
            I'm thinking the only way to settle this is for someone to ask the question to get a proper answer to what alloy is it?

            "The Benelli USA company told me there was NOTHING they could do to fix the gun."

            Understandable. They aren't in the business to repair are they? But would they sell you a new part or are they also unavailable?
            Did you ask, what grade of Aluminum is the alloy being used? Did you talk to someone who new something or a call center service responder who said we don't do those repairs?

            "Benelli has total confidence in its products and backs every gun with an industry-leading 10-year warranty."

            Missed it by that much it seems? Well...throw it away and buy a new one? Seems a workable solution? Welding didn't work?
            Maybe it is unweldable? Or maybe the Doctor misdiagnosed the mole and the cancer has spread? Didn't cut it all out? Hard to say? I'm going to give you points for trying. Enjoy the new gun.

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            • #21
              dvice...I'm really hoping you breath deeply, think about what's been said, and again ask, is it weldable? Maybe it's not? But if it is, you can do it. These aren't my weld, or my pictures. The first two, they show aluminum welds that for lack of better, were welded slower and colder. Drop after drop, with a little higher heat and melt it at the base.

              The last picture, someone was practicing and learning. Granted some are going to say ugly as sin, give up go home and pay a real welder. I say good effort, learning something, and I see some sections that show potential.

              Humility is a great teacher. After doing the silly welder trick of joining pop cans I was asked, could I do it if they were full? My reply was, while they are a vessel under pressure, in theory, if I don't melt enough to penetrate, or soften as to weaken the material enough to cause rupture from the pressure...it could be do able.

              Hires Root Beer and Orange Crush...
              Pop every where, no one died, and I became known as the guy who tried.
              I still think it's do able?

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              • #22
                Originally posted by Noel View Post

                Hires Root Beer and Orange Crush...
                Pop every where, no one died, and I became known as the guy who tried.
                I still think it's do able?
                Bring us along on this journey of discovery, post the video
                Richard
                West coast of Florida

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                • #23
                  Job security for guys like me.

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                  • #24
                    Fatigue failure. I'd say the receiver is roached. Not that it owes you anything after 40 cases of 3.5" shells...

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                    • #25
                      I do think it's safe to say that it's definitely junk now.
                      That shape would have had a tendency to crack no matter what the material was.
                      The entire part should have been pre-heated before welding and kept hot uniformly until cooled. And that is welding it like Noel describes.
                      If the part is Billet then there is a good chance it could be 7075. If it is cast there is a possibility it could be a pot metal.
                      By the picture I would seem much effort was not to disturb the surrounding area...as in grinding through 100% and worries in regard to requiring additional machining. I get that. But you usually only get one good shot at a part like that.
                      I would say from the pic you have way too much dilution from the parent metal and too much contraction from the rest of the part not being up to temp.
                      When you commit to welding a piece like that you pretty much threw heat treat out the window, but you can't have the only soft area the spot that is the weakest. It's no different when you weld a small area in the middle of a transmission case. Pre and post heat are vital when welding a bridged area.
                      treat it like it's cast iron and you can't go wrong.
                      This is simply my opinion, based on all the junk I've either succeeded or failed at repairing. Either way if you haven't determined if it's cast or billet you are simply guessing blindfolded. (and once again in my opinion and with no intent to offend anyone)

                      www.facebook.com/outbackaluminumwelding
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                      • #26
                        https://phys.org/news/2019-01-nanote...n-weldable.amp

                        When ever there is a problem, someone goes looking for a solution, seems they've found one? Shout out to the folks at UCLA.

                        https://www.nature.com/articles/s41467-018-07989-y
                        Last edited by Noel; 01-26-2019, 11:09 AM. Reason: Just read the original article.Interesting enough I thought to add the link, explanation is highly understandable.

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                        • #27
                          OK.....where do I get my Nano-rod ?

                          www.facebook.com/outbackaluminumwelding
                          Miller Dynasty 700...OH YEA BABY!!
                          MM 350P...PULSE SPRAYIN' MONSTER
                          Miller Dynasty 280 with AC independent expansion card
                          Miller Dynasty 200 DX "Blue Lightning"

                          Miller Bobcat 225 NT (what I began my present Biz with!)
                          Miller 30-A Spoolgun
                          Miller WC-115-A
                          Miller Spectrum 300
                          Miller 225 Thunderbolt (my first machine bought new 1980)
                          Miller Digital Elite Titanium 9400

                          Comment


                          • #28
                            If we pool our money together we might be able to afford a tube of the stuff.

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                            • #29
                              I doubt it

                              www.facebook.com/outbackaluminumwelding
                              Miller Dynasty 700...OH YEA BABY!!
                              MM 350P...PULSE SPRAYIN' MONSTER
                              Miller Dynasty 280 with AC independent expansion card
                              Miller Dynasty 200 DX "Blue Lightning"

                              Miller Bobcat 225 NT (what I began my present Biz with!)
                              Miller 30-A Spoolgun
                              Miller WC-115-A
                              Miller Spectrum 300
                              Miller 225 Thunderbolt (my first machine bought new 1980)
                              Miller Digital Elite Titanium 9400

                              Comment


                              • #30
                                Originally posted by FusionKing View Post
                                I do think it's safe to say that it's definitely junk now.
                                That shape would have had a tendency to crack no matter what the material was.
                                The entire part should have been pre-heated before welding and kept hot uniformly until cooled. And that is welding it like Noel describes.
                                If the part is Billet then there is a good chance it could be 7075. If it is cast there is a possibility it could be a pot metal.
                                By the picture I would seem much effort was not to disturb the surrounding area...as in grinding through 100% and worries in regard to requiring additional machining. I get that. But you usually only get one good shot at a part like that.
                                I would say from the pic you have way too much dilution from the parent metal and too much contraction from the rest of the part not being up to temp.
                                When you commit to welding a piece like that you pretty much threw heat treat out the window, but you can't have the only soft area the spot that is the weakest. It's no different when you weld a small area in the middle of a transmission case. Pre and post heat are vital when welding a bridged area.
                                treat it like it's cast iron and you can't go wrong.
                                This is simply my opinion, based on all the junk I've either succeeded or failed at repairing. Either way if you haven't determined if it's cast or billet you are simply guessing blindfolded. (and once again in my opinion and with no intent to offend anyone)
                                there was NOTHING to lose trying to repair this reciever... the first issue was contamination.. from anodization UNDERNEAT where I was welding..eventually I sand blasted it..i think it welds fine..it just cracks.. afterwards.. and since it was such a THIN section( thinner than most thinking because of acme threads underneath) I had to build it up and try to flow it out to the receiver... I dont mind the blob as I machine it back down to size!... Ive dont many welds....I dont do it for money and if it is good enough Im happy... I welded this gas tank filler 3 weeks ago... and i build an 8 foot long fuel tank for my boat out of .090" aluminum 24" wide and v shaped on the bottom...i tacked it at home with my MIG machine and brought it to work and tigged it closed. just sometimes you get a DIFFICULT job... for your own skill level

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