Welding Rod brands DO make a difference: see this testimonial about a 140ST.

[jerky]

All the boxes are hermatically sealed in plastic. Ill post a pic of the fingernail when i get home

[performance]

Plastic isn't considered hermetically sealed. It must be in a negative vacuum can.

Fingernailing is often a result of improper rod angle. I know on the type of equipment you are working, it is impossible to control at times...I have welded with some mighty fine Exaclibur at times in out of position, or in a pretzel position and finger nailing would still happen.

[dblake22]

If you are having contaminations problems, it is as Mark says, you have to bake those rods. Per the lable picture provided 8 posts above, you need to bake at 350 C (662 F) for two hours.