welding 6061 T6 aluminum for testing

[ghead]

I am doing a welding test in 1g on .040 6061 T6 aluminum for an aircraft ticket. My cap looks great but my root pass gets a line almost like a seam all the way along the weld. I hope someone knows what I am talking about? People I have talked to say that it is always there, Any takers why or how to maybe cure the flaw?

 

[metengr]

The crease you are referring to normally occurs along the centerline of the weld deposit, and is not that uncommon. If you are spotting it after pulling the root, it could be caused by excessive root gap (or opening) or how the weld beads tie into the side walls of the weld groove. It is not normally injurious, and is more cosmetic in appearance.

I presume you are using GTAW. If so, you could try to manipulate bead placement, adjust the root gap or your travel speed when pulling the root.

 

[pandithan]

could you pl elaborate more

 

[pandithan]

This is a oxide, not to worry ,but you have to clean the joint with acetone followed by mechanical brushing, cleanig is very important, after cleaning, welding is to started within 3 hours