First FCAW weld on 1/8th Wall Pipe

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Pipe is 1 1/4" normal mild steel. I notched it with a hole saw and jig and then welded it with FCAW. I didn't do it in one shot, instead I tacked it and welded it basically in quarters, brushing off after each quarter with my wire cup mounted in my grinder. I took an inside shot of the pipe welded to and you can see the ring from the weld. I am not sure if I need to crank up the heat to get more penetration or if what I got is perfect. Not perfect but its a start. I am concerned about the cavity cut out of the base metal where the weld meets the base metal (last shot close up). I think this would be undercut. I I believe that is not a good idea so I would appreciate suggestions. Constructive criticism is solicited and appreciated.Victor Journeyman OA TorchVictor Edge RegulatorsLincoln 180HD (240v) MIG/FCAWShark LT v7 CADMiller Digital Elite Helmet35 Milligrams of Insanity
Reply:Pipe welding is an art. I am not a pipe weldor, but here is some good reading to give you an idea of what goes into good pipe welds. http://www.gowelding.org/Pipe_Weldin...ification.htmlKeep Practicing!!! City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Originally Posted by tanglediverPipe welding is an art. I am not a pipe weldor, but here is some good reading to give you an idea of what goes into good pipe welds. http://www.gowelding.org/Pipe_Weldin...ification.htmlKeep Practicing!!!
Reply:It looks like you are starting and stopping [B]a lot[B] Why?It you are trying for MIG like TIG STOPYou should be pulling the trigger as few times as you can to make one continuous bead around the joint. All them bumps humps dips create stress risers and make the joint weaker. Plus its is just plain ugly. Sorry.
Reply:Originally Posted by Fat Bastardaround the joint. All them bumps humps dips create stress risers and make the joint weaker. Plus its is just plain ugly. Sorry.
Reply:Originally Posted by Fat BastardIt looks like you are starting and stopping [B]a lot[B] Why?It you are trying for MIG like TIG STOPYou should be pulling the trigger as few times as you can to make one continuous bead around the joint. All them bumps humps dips create stress risers and make the joint weaker. Plus its is just plain ugly. Sorry.
Reply:Are you triggering the weld in as in rapid trigger pulls to create that look?Looks like you are weaving around too much.Try small circles about 2x the diameter of the wire. Try to run the bead in is quarters 12:00-3:00, 3:00-6:00, 6:00-9:00, 9:00-12:00. At each termination point grind a small amount of the bead back to create a ramp, restart at the bottom of the ramp. Once the arc is stable pull back up the ramp pause for a fraction of a second then continue the bead to the next quarter. Repeat...
Reply:Originally Posted by Broccoli1Kinda looks like yer Avatar
Reply:Originally Posted by Rellsbecause I am not flexible and young enough to crawl under the table while maintaining the weld? I would like to do it in one pass but honestly I cant see the whole weld at once.As for ugly *shrug* it is only a start and I would rather get proper fusion than prettyness.
Reply:You should be able to do this with 2 runs max. One on side "A" and one on side "B", 1/2 at a time. If you can get over top the joint you can do it it one pass, but that will take a lot more practice until you are at that point. I'm still working on tube joints. I can do these in 2 passes. The guy who's helping me and who does this all the time can do that 3 pipe cope I posted up in one pass. He'd wrap the gun around the right side and lean thru the center. He'll start on the far center and weld around the right tube 100% and continue around the left tube and end back at the start. His welds are not as pretty as ZT's, but they pass Xray and NDT tests every time. He does structural welds on tube on crane booms where there's really no margin for errors. I'll see if I've got a practice piece of mine  in the garage to post up if I can find the camera.It's not easy. You will have to keep changing the gun angle as you move and keep a consistent speed. Ignore weaves at this point, all it will do is complicate an already difficult weld. Start with the basics. Can you get good welds in all positions on flat plate, flat, vert, horiz and overhead? If not you won't get nice welds on pipe as it moves usually thru 3 of the 4 positions at least. You need to transition thru all of these seamlessly to have a good weld. If you are fighting getting good consistent welds on flat plate, you are wasting your time and possibly just learning bad habits that will be hard to break. Pipe welds and tube welds really are not all that different in small sizes. Big pipe is easy to weld. It will act like flat plate. Small pipe/tube will require you to quickly transition thru the different positions as you move. All those starts and stops just makes for more weak points that are harder to get right. Attached ImagesLast edited by DSW; 03-04-2010 at 04:33 PM..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Its definatly a start. try and position yourself so you are comfortable, do a couple practice runs with the gun without welding, just run it along like you were going to weld it and follow the joint, this way you can see how you might need to adjust yourself to make sure you can follow through and weld all you can in one pass. Its a combo between muscle memory and plannin out your weld, I learned this when i was starting out but forgotten it over time, then i was watching this awesome welder i worked with who did this before every weld he did, not much for reading prints or fabricating, but man could he run a bead. I thought when you got good enough you didnt need to do it anymore, but it can help anyone.Nothing Ever Got Done By Quitting, Never Give Up.
Reply:@DSW: When it comes to FCAW I have run a ton of practice welds including lap welds, fillet welds and flat welds. I can do them reliably though I have more difficulty with uphill vertical. Oddly enough overhead doesn't flummox me like uphill vertical. At any rate, this is my first foray into tubing and a necessary one given what I would like to try building. I was weaving a bit, as I tried to put more heat into the cross pipe than the connecting one. Its an old torch habit. One that perhaps I need to break for MIG. You would just run it straight on the edge pointed at the junction of pipes? That could be interesting.@Doug247 : Good advice on the dry runs. I do this with firarms to work on holster and trigger technique and I am sure it would work just as well with welding. Thanks.Victor Journeyman OA TorchVictor Edge RegulatorsLincoln 180HD (240v) MIG/FCAWShark LT v7 CADMiller Digital Elite Helmet35 Milligrams of Insanity