Overhead Welding with 7018 Stick rod in Rooftop position

Video on 4f Stick welding overhead with 3/32” 7018 on weldmonger blog

Clams for stick welding overhead stands for 

Current and Cleaning, Length of Arc, Angle, manipulation, and speed of travel.

The Clams acronym prompts us to as the following questions:

How clean does the metal need to be?

What polarity and amperage?

How long should my arc length be?

How should I manipulate the electrode…or should I NOT manipulate at all?

How slow or fast should I travel?

How clean does the metal need to be?

Stick electrodes will penetrate thru hot rolled mill scale.  But undercut will be much less likely if mill scale is removed with a grinder.

What polarity and amperage? 

Generally DCEP is the recommended and preferred polarity for 7018 rods and one amp per thousandths of thickness will get you pretty close on amperage.  So a 1/8” 7018 is .125” and 125 amps is a great starting point for amperage whether overhead or flat.  A 3/32” 7018 is .094” so 94 amps might be a tad hot for some brands but is still a good starting amperage for some brands of  3/32” 7018.

How long should my arc length be?

rule of thumb for arc length is one electrode diameter but remember that the core of 7018 is recessed inside the cone created by the way the flux melts off.  Even a tight arc will be longer than you might think due to the solid metal core of the rod burning up inside the flux coating.

My age old advice for stick welding overhead with a 7018 is to set machine where the rod won’t stick when you hold a tight arc…then hold a tight arc.

(The Arc control aka Dig setting can definitely affect how tight an arc you can hold at a given amperage but that’s a topic for a different video and article.)

How should I manipulate the electrode…or should I not manipulate it at all?

no manipulation is required but sometimes it helps the bead flatten out.

How slow or fast should I travel?

travel slow enough to avoid undercut. But go fast enough to prevent a highly crowned bead.