7018 Rods

[trich]

I started welding for a new company that uses Atom Arc electrodes for their 7018 use. I passed one test but showed a small amount of porosity on the final start of my last cap pass and have to re-take it. I noticed that there seems to be quite a bit of splatter with this rod and was wondering if anyone else has had any trouble with it? In the past I have always used a Lincoln rod with good success. The slag peels of the Lincoln rod and does not with the Atom Arc no matter which technique or temp I run. I talked the inspector in to getting me another rod made by lincon which is called Murex 7018 MR ( MR rated for moisture resistance). The porosity I encountered seems to be surface porosity which is usually due to moisture. Any feedback on this rod would also be appreciated. Thanks

[ok weldor]

Hey Trich
I don't want to come off as insulting your intelligence. If you are working in a refinery you know your stuff.I have used Atom Arc rods quite a bit with no problems. If you were testing and not familiar with the machine,is there a chance the polarity was wrong.
The murex rods weld pretty good as well.
It could have just been a fluke, nobody weld's 100% all the time.

[revpol]

Have seen this problem in the past with porosity. Myself I never had a problem with it only when I first started using it I had to learn that it starts a little slower than most other lo-high. If you had a stick of atom-arc in one hand and linc. in the other you would probably notice that the atom arc flux is a tiny bit thicker which tells me that it would start slower. So on starts I usually weave the rod just a little more than a natural shake of the hand. With the heat set right never have a problem getting the slag to curl. revpol

[DLN]

We had a lot of probs with that...only in the first 1/2 inch or so.....it got so bad we stoped useing it......but if you have to use it, make sure its very dry......or just start real slow, and let a little of the end burn off ...DL