porosity in 1/8 7018

How do I eliminate the porosity (or what causes it) in a pipe welded with
1/8 7018 on 4"+ pipe?
I've had this problem before, and I would like to eliminate it.
I beleive that I may be holding the rod out too far at times (the porosity
is sporadic).
If that's the case, can I hold the tip right into the puddle, or just about
into the puddle?
Thanks to all.
Reply to
Some1
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Yes you must hold a tight arc with 7018. The electrode will tolerate being run as a contact rod. What I mean is that the shoulder of the flux can be rested against the parent metal as you travel along. It is almost impossible to get that tip too close once the tip is burning hot. Randy
How do I eliminate the porosity (or what causes it) in a pipe welded with 1/8 7018 on 4"+ pipe? I've had this problem before, and I would like to eliminate it. I beleive that I may be holding the rod out too far at times (the porosity is sporadic). If that's the case, can I hold the tip right into the puddle, or just about into the puddle? Thanks to all.
-- marc snipped-for-privacy@REMOVETHISyahoo.com
Reply to
R. Zimmerman
First thing is your rod may not be dry. 7018, of course, should be kept in a rod oven from the time it is removed from the sealed shipping container. If the rod is exposed to air, especially humid air, for much time, it will pick up hydrogen from the air (remember, this is a low-hydrogen rod). In the weld, the hydrogen can form bubbles, ergo porosity.
Second thing you already know about is arc length. Keep it as short as you can. Pipe can be tough because the angle is always changing. Takes a lot of practice to be really good at pipe. I generally backstep my welds because I have never gotten the hang of keeping the rod angle and puddle speed constant while welding around a pipe.
GWE
Reply to
Grant Erwin
Another thing to look at is the brand rod you're using. There's some 7018's out there that it's almost impossible to keep porosity out of.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
Lately I've been using Excalibur brand 7018. Ernie uses it at his welding school, and it burns real sweet. It's only a few pennies per pound more.
GWE
Reply to
Grant Erwin
Hello to this group...I've been away..(I am a long time old-time stickwelder fuddy-duddy}.A quick check to see if your problem is caused by moisture in the coating. At a lower current setting, say 60 amps. for 1/8" 7018...stick the rod to the work in a direct short circuit "no arc" contact. Allow rod to heat up for about 10 t0 20 seconds "until the rod starts to "steam off moisture" don't let it get so hot as to damage coating {STEAM NOT SMOKE!} or get red hot. Then set current for your normal welding job and make a weld. You will have a "low hydrogen coating again" . If you still get porosity, it is not from moisture in the coating, but may be from other conditions.
Reply to
alphonse
I've heard of it but I've not tried it yet. I do know that Lincoln makes several kinds of 7018 and some of them are absolutely lousy. I've used one in the past that would always start and end a weld with porosity no matter what you did and if extreme care wasn't taken then porosity would show up in the middle of the weld as well. Another form a 7018 Lincoln made was pretty good except that it was a real bear to restrike. My current box of 1/8" rod is Murex that's made by Lincoln and is one of the worst that I've run a in a long time. It makes decent welds if you run it right but the flux just falls off if you're not careful and it tends to spatter more than I like. IIRC Excaliber is a new 7018 version from Lincoln. I'll have to try it some time though I hate buying a 50 pound box of rod to only find that I hate it (which is my current problem with the Murex).
Personally I've had pretty good luck with Hobart rods in the past. Unfortunately my new welding supplier doesn't stock them. I do think that Hobart rods have gone down hill quality wise from what they where before Hobart got parted out. At one time they where one of the sweetest rods I've ever run.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
Buy a 10# box, then. I have 2 10# welding rod ovens and keep ten pounds of 3/32" and 1/8" 7018 in each. I know just what you mean about crummy 7018, I slogged my way through about 90 pounds of rod with pieces of coating falling off, etc. Having new hot top-grade rod is a real treat compared to that stuff.
GWE
Reply to
Grant Erwin
I just hate paying the price per pound for the 10# boxes (it's like double the price for 50#). I talked to the store manager about it and he's supposed to get me some samples of the different rods they stock but I'll probably have to remind him. He's rather busy and tends to forget stuff like that.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
Thanks to all, you've all been useful...I knew some of this already, but had to reaffirm it. I was always worried about sticking the tip of the rod in the puddle out of fear of getting some kind of slag inclusions in the welds.
Reply to
Some1
I have run into this problem before but I was not getting a good hot start. My SA200 was at idle and not on high idle. Eliminated porosity after that. I didn't see what you are using, may not apply to you if you are not using a engine driven machine.
Reply to
Jess
At South Seattle Comm Coll, we have tried many rods. The Hobart and Murex rods are cheap and kind of work, but they are not great rods.
Lincoln makes the best 6010 and 7018 I have ever used. The Lincoln Excalibur 7018 rods are just the best. I have also used UTP's 7018 version, which they call 718. Really nice stuff, but really expensive.
Reply to
Ernie Leimkuhler
- Wayne Cook - spluttered in news: snipped-for-privacy@4ax.com:
Lincoln used to make some MR prefixed rod. 7018. Moisture resistant, afaik.
I think it ran better than the bone-stock 7018 Lincoln stuff, which is what I learned low-hyd on. Bleagh, extremely moisture sensitive.
My current box of 1/8" rod is
Reply to
Sano
Ok. That's a good recommendation for the Excalibur. Lincoln's always been the company for 6010 though I've never used much of it. I prefer 6011 for most of my dirty work and in the past I definitely didn't like the Lincoln 6011 (they made two kinds back then).
At the time I was using Lincoln 7018's I was working at my former employer. They made like 5 or 6 different 7018's at that time and we tried several. There was some that where ok except for the restrike which is common for good 7018's in my experience. But my employer didn't like them because of that. He went to buying another kind that did restrike pretty well but was lousy for porosity. Of course it didn't help that they left the rods out in the open all the time. At first there wasn't even a door on the welding part of the shop and the rods where out in open bins just asking to get wet. We finally made a door and later I finally convinced them to at least get a old refrigerator to put the rods in. I never did manage to get them to put a light bulb in it though.
I must admit that I don't store the rods as well as I should. I've just never gotten around to making a proper storage for my 7018's. I do keep them in a old commercial double door freezer with all my other welding stuff. But there's to many other things in there to just put a light bulb in it for heat. I need to partition off a portion to use for rod storage so I can add some heat to it. Just not enough round tuit's available to get there yet.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
I've seen it but never tried it. By the time they came out with that I was already on my own and preferred the Hobart rods at the time.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
The restrike issue on these 7018 was a killer for me. Very frustrating. I finaly switched my stick lead to the tig terminal and started using HF arc starting even on welding rods.
i
Reply to
Ignoramus6607
Grant, you are 100% right. I tried removing glass by just scratching the rod on rough concrete. Still, it is nice to use HF and not worry about restrike. (and TIG is even nicer)
i
Reply to
Ignoramus6607
Restrike isn't too bad if you first break off the glassy slag that covers the end of the rod. Ernie welds 7018 holding a chunk of metal in his left hand which he uses to poke the rod onto. I normally have an old hammer lying on my welding table which I use to "dress" the tip of the rod before restrike. If you look at it carefully after a short pass, then knock off the glass and look again, it's pretty obvious. I use 7018 a lot and I'm pretty used to it.
GWE
Reply to
Grant Erwin
The key to restriking 7018 is to rub the tip on a piece of stone or concrete before trying to restrike. This cleans the little glaze of flux that ends up on the end of the rod.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook
The only problem with using HF with stick is that the electrode holder isn't insulated for it. Thus it's likely that at some point in time you'll get a shock from the HF. As long as you use dry gloves and keep the holder away from your skin you'll be ok but at some point in time it's probable that you'll forget. It's not dangerous but it can hurt.
Wayne Cook Shamrock, TX
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Reply to
Wayne Cook

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