what can you tell? (MIG)

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after practicing some more, finding a comforatable setting for me, I started on my project. It was to raise he frame 1 inch to set the front crossmember even with the frame. I had some problems, and I have to redo it, but the weld pictured held. lincoln 175 pro mig, .035 flux core. heat C wire speed ~3Why is it black? What else can you tell me?I don't want to go into details on what went wrong, it's not important really, just thats its going to be fixed one way or another.Last edited by GrantH; 08-11-2008 at 01:48 PM.
Reply:The weld looks good. I have no issues to raise from the supplied photo. The application of the weld now that is a different story! As you say the weld will not be used as you are fixing the issue another way. If the frame is going to be used on the public highways and is going to be put back to the original position and welded then I would have major issues with the joint design. And with a novice welding it. Please tell us that this is some off road use only vehicle. Good luck.TJ
Reply:thats not finished by any means. at all. that was merely getting into position and laying a bead. that was to be ground down, the other side to match, and have a plate, to place over the joint, with 3 inches on either side of the weld, weld that solid, and cap the bottom and top. its been done numerous times like this, exactly, with no problems. the clip is being redone is what i meant, some things went wrong and it all has to be redone fully. its all good.
Reply:Well, personally on a frame I would much rather see a weld going uphill than pulling it down.  it will give a canvex bead instead of a concave.   Secondly, I think you might need to clean a little more.  Did you just cut the frame and jack it up an inch and weld it back together?  If so you need a lot better joint design.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:no, it was cleaned with a 80 grit flap disc and wire brush a half inch or 3/4 outside the joint on the far side and a good bit in the front. the flash is playing tricks off the steel as its dark regardless of lighting in that are. thats one reason i did go downhill, i couldnt see crap going uphill when i did the driver side. it may be contaminated a bit, im not saying that it wasnt just i think i cleaned it enough maybe some acetone next time. also there is antispatter spray on it.
Reply:Well I'm not trying to be a smart@$$ by anymeans, but I think you have caused your self alot of porblems down the road.  Auto frames are tough to repair and make last in the first place.  I sure wouldn't cut a perfectly good one for an inch difference, but to each their own.  You really need to figure the joint so that the top and bottom flanges are tied back together, not just the web.  Also I would go more than 3" either side of the weld, and make sure not to weld perpendicular to the frame.  This is a good job for a pro.  As a hobbiest you have your work cut out for you.  Good luck  ~JacksonI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:that was not a finished project.....i dont see why anyone would even think that.the top and bottom open areas were going to be caped with 2x3 cut to fit perfectly and welded up and THEN have plates going over the whole area with the ends going to a point to spread the loads put on that area out as far as they could.i didnt go into detail, as I only asked about the weld, but if we are going to go into detail about what happened then lets go into detail. i welded up and plated the driver side frame rails and was not happy with how i had done it, and being a perfetionist i was taking it to a welding shop a buddy of mine uses for numerous jobs. they offered to weld it up for no charge aside from the metal to cap/plate it as i was a good friend with their good friend. i welded up what your calling the web, the pic shown, and thought it would hold well enough to roll it back on a trailor. we have a weird shaped driveway so we pushed it out and turned it to the straight part of the driveway. in the process it twisted/buckled/whatever. it was NOT finished. it wasn't even close. it was merely lined up for a better suited welder to do the job.cutting one up for an inch of clearance.....ill leave my thoughts out of that, as it was needed in my eyes. and the frame work if done correctly is not hard, hard to repair...yes....but i didnt "mess up" majorly until i set it on the ground and made a stupid mistake of moving it.
Reply:From what I can see, and what you've already been told, looks to me like you've created a lot more problems than you'll solve.You seem to already have "all the answers" which leads me to the question of what was it you wanted to know in the first place.From the design to your comment about welding the joint down leads me to believe you're in over your head and should take the part (vehicle) to a professional and have it repaired properly (if possible after initial surgery).As Hammack and FB have already stated, frame repairs/modifications are not a job for a guy "practicing his welding".Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:what i wanted to know is what i could do to improve the weld, not get in a debate of whether or not i should have been doing the project.
Reply:Originally Posted by SundownIIIFrom what I can see, and what you've already been told, looks to me like you've created a lot more problems than you'll solve.You seem to already have "all the answers" which leads me to the question of what was it you wanted to know in the first place.From the design to your comment about welding the joint down leads me to believe you're in over your head and should take the part (vehicle) to a professional and have it repaired properly (if possible after initial surgery).As Hammack and FB have already stated, frame repairs/modifications are not a job for a guy "practicing his welding".
Reply:once i got going i really wasn't 100% confident in doing this fully so i wanted to get it together, get it to someone else, and have them finish. i figured i was doing the smart thing. i guess noticing half way thru is no better than all the way through the job now.
Reply:The black on the bare weld bead probably comes from early or immediate exposure to air, in short, little to no slag coverage. I see some slag towards the top, none at the bottom. Some self shielded flux cores seem more prone to the blackening than others.  What wire were you using? A thin flux core bead in a butt joint like that, left as is, can be pretty brittle and prone to cracking.
Reply:One trick that you might file away for temporary assemblies is to tack as you have then place a couple of "strongbacks" across the joint.  In this case it would be two pieces of 1/4 x2 inch about six to eight inches long tacked standing perpendicular to give rigidity.  Weld on one side only of the flat bar so that later you can just snap them off with a crescent wrench.    I am not going into where the tacks should be located and whether you should tack anywhere on a frame.  That is another argument/discussion.  Oh Yeh....  Generally tacks should be one inch or longer.  This reduces the sudden heating/cooling effect and the resulting brittle area.Last edited by lotechman; 08-12-2008 at 08:53 AM.