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Cast welding - failure.....

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  • #16
    Brass/Bronze rod has a higher tensile strength than most arc welding rod. It is what is holding your frame and front end together.

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    • #17
      I can’t completely agree with that statement. Although advertised tensile strengths are similar, brazing depends on surface contact for strength. If you butt braze two pieces of sheet metal together the joint would break easily. A butt weld would be as strong as the base metal. It’s true that brazing was used to hold those frame and front end parts together. They used slip joints in which the joining parts had a lot of surface area in contact with each other. I have an Indian 741 frame on my work bench right now and the factory slip joints were tack welded (to hold them in position) and then brazed. Capillary action draws the brass into the joint like soldered plumbing joints. When done this way a brazed joint is very strong. In tension, there is so much surface area brazed together that you’d never be able to pull the joint apart. Axial or side loads are absorbed by the base metals, the tube and it’s casting, and the support that they give each other is critical to the strength of the joint. A butt brazed joint would not be strong enough. Brazing that frame joint might work for a while but without a little extra support I’d expect it to eventually fail. Looking closely at the photos it appears that the issue with welding was penetration. Preheating the parts will help this a lot. The cracked area should also be V’d out a little to aid in penetration and to allow more of a weld to remain when the area is ground smooth. I’m sure the frame fittings are cast steel so I go along with Bar’s rod recommendations. Although I’ve always found that the 7018 rod makes an ugly weld, the penetration and tensile strength are superior and the 6011 rod makes a nice cover up. This is very strong weld and is fairly easy to perform. It was actually the first type of weld that they taught us in the (limited) welding classes I attended. Let the weld cool slowly, DON’T quench it with water.

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      • #18
        The lug when ground was a light straw color. Not alot of spark.

        Yes- I have to make my "V" much deeper. I have a carbide grinder bit.

        I'll go pick up some 7018 and 6011 rod.

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        • #19
          I never had to depend much on spark testing but iron gives off a fairly red spark as compared to steel's bright yellow or white. Here's a pretty good description. http://shopswarf.orcon.net.nz/spark.html
          I'd really need to be able to spark the different steels side by side to tell the difference but that's me.
          Try pre-heating before you weld, it really seems to make a difference for me. It doesn't need to be too hot, if it sizzles when you spit on it, that's hot enough.

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          • #20
            For cast iron I use gas, and have had great luck.
            I keep it clean, V it out to about 1/3, pre-heat and use piston rings held in visegrips for filler.
            Your welds lacked penetration.
            You need a puddle!
            And start getting the filler in fast.
            That melted cast iron likes to run away.
            If that casting really is iron, of course.
            My 40 SS was well fixed before I bought it.
            I wish I could ask it how the job was done!

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            • #21
              Success! Used the 7013 standard rod and pushed it into the V. Lots of penetration on underside. Added a gusset weld under also. My spark up got better as time wore on. Touching and just heating up the rod first was a good tip. Cleaning the surface and the **** from rod tip to start new also helps. Drag/scratch on concrete. So I got into the swing of things tonight. Laying on your side and welding is not that easy. Another trick was to cut a rod in half if your hand shakes too much.

              Touched up the arm also at the stop point. Also looks like it was dragged down the highway at some point. So I built the foot back up.

              I got a good pool going and just let that ****er cook. Took my time, left side , right side. Ground it down and a little hand filing. She looks good, sits right, feels solid. I figure with the hours I have into my side stand on this 640 now from the get go. It must be worth approx 1200.00 USD. Seriously. Yup.....complete insanity.

              Much thanks for all your help guys. I really appreciate it.

              Well, now that I have a side stand again. Should I remove the center stand?

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              • #22
                Well congragulations! I think you mean 7014 rod not 7013. By the way the rod numbers have a meaning. The first two digits give the tensile strength as in "70" is 70,000 psi and the third tells you the "position" that the rod is intended to be used in. 1 means "any position, 2 means "horizontal and flat" 3 means "flat" only. The fourth digit is as follows 1 means "AC" or "DC reverse polarity" (rod is the negative side of the circuit), 2 is "AC" or "straight" polarity, 3 is "AC or DC of either polarity", 4 is"AC or"DC positive polarity", 5 is "DC reverse polarity"and 6 is "AC" similar to number5. Now that you know more than you wanted to I'd have to conclude that these are good guidelines but you can probably get rods to weld in other positions, but not very well. Let me know when you are good enough to weld overhead so I can bring my jobs over for you to weld instead of turning them upside down so I can do it in the flat position .

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                • #23
                  That's good news. It sounds like you're in good shape now. Better keep the center stand. Can you put a Scout on the center stand and lean it over onto the side stand to remove the wheels like on a Chief? By the way, I noticed in my last long winded post that I reversed the rod use. In school we would use a 6010 or 6011 for the first pass because it gives better penetration. It also made an ugly weld so we'd cover it with a couple of passes with the 7018. The 7018 makes a smooth, pretty weld and the 8 means low hydrogen which makes it a ductile weld. I never tried a 7014. Which one did you use?

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                  • #24
                    7018 is a low hydrogen rod and would be used for the whole weld to minimize hydrogen embrittlement. To layer a weld otherwise either 6010 or 6011 would be used for the first pass because they are deep penetration for the root of thr weld and 7014 would be used for the rest of the weld as it is a iron powder rod with fast fill and an exceptional finish.

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                    • #25
                      Bar, in the class they made us use 6010 covered with 7018. It's been a while since then so I even dug out the Hobart book they gave us just to make sure and it's in there too. In the Hobart book they reccomend that combination for open root welds but the instructors had us do it with flat "T" welds too. They claimed it was the best combination for high penetration and strength. The instructors were all old experienced welders and I was a dumb machinist so I just learned it the way they wanted me to. I remember that we sure burned up a ton of 6010 and 7018 rods. They never gave us any 7014. I googled it and it looks like a nice rod. It's probably what they should have given us since it fills well and all we really needed to learn was how to do build up. I still don't consider myself a welder but I was able to learn enough to keep my junk stuck together.

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                      • #26
                        Sorry, I used 7018.

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                        • #27
                          That's a good one, probably the best. We've kicked a couple of methods back and forth but any of those rods are quite capable of doing the job by itself.

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                          • #28
                            Again thanks for your help guys.

                            I cheated and built up the foot for a little more surface area. I can park the bike on the lawn, use the side stand and it won't sink in. I like that. One less headache.

                            Just discovered my rear hollow axel has snapped off the threaded portion with the nut. SO now I have to find one of those. I don't think anyone makes these. *(&$&^%#&^$#
                            And I'm confounded at how the frig it happened in the first place.
                            Another puzzle to figure out.

                            I heat treated a steel rod in used motor oil today. What do you think the rockwell hardness of it is?

                            Went for a little break-in ride late this aft. So cool when you rebuild an engine and it starts first kick. Set off a number of car alarms for some strange reason. Rode by the vetrans building. Just sat out front across the street and let it idle. SUre enough all the boys were up at the windows to have a good look see. I know a couple of DR riders are in this building. I've talked to them.

                            Kid on a jap bike thought my old bike was pretty cool. Said he had never seen anything that old running before. So I gave him a card.

                            An approx 45yr old guy and his gal pulled me over to take a good look. It's easy to forget how much attention an older bike gets.

                            I think I'm going to regrease my front girder. I'm not getting good movement. Maybe the clutch pedal also.

                            Blah, blah, blah...... over and out.

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                            • #29
                              My rear axle did the same thing about 4 years ago, right where the threads start. Took it to Johnny Eagles hoping to get a replacement. He did'nt have a match, he brased it and I have been riding it since with no problems. I redid my bearings about a year ago, thought for sure it would be broke again - but it was fine. Glad to hear your SS back up, right on!!

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                              • #30
                                OK a braze job it is. Or TIG. It's sloppy right now - as the main and spacers are holding the bearings in place on right side. Not good.
                                I'll give the bearings a dry slop check. Hopefully no damage.

                                Back up and only one head bolt leak. Removed the bolt -gooped it up and washer and she's fine now. No leaks! Kinda shocking for a hack like me.

                                How often does one bend or warp a solid main axel on a rigid?

                                Took an old hockey stick to the girder tonight. She moves. Maybe oil not grease is what it needs.

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