When using a stick welder it is often not easy to begin an arc exactly where you want it. Some risk damage to their eyes by peeking out from under the hood. But, a carbon rod allows starting a bead exactly where you want it to begin.
The piece of steel in the photo is about 3 inches across. I ground the paint away so an arc can start easily. The arrows were made with a felt tip pen. This Instructable will show how to start an arc in the center area between the four arrows.
The portion with paint removed at the lower right corner of the photo is only a place to attach the welder's ground clamp.
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Step 1: Prepare and Positon a Carbon Rod
Welding supply houses usually sell carbon rods. These come with a heavy copper foil on them. Touch the foil to a grinding wheel from the tip back a couple of inches. Peel the foil away from the rod.
Touch the tip of the carbon rod to the steel just behind the point where the bead is to begin. Be sure to wear welder's gloves.
Step 2: Cross the Electrode Over the Carbon Rod
Cross the electrode over the carbon rod from behind the carbon rod as shown in the photo. Without moving the placement of the carbon rod or the electrode, shake your head once to flip your welding helmet down to cover your face so you are ready to weld.
Step 3: Start the Arc
For purposes of the photo, the welder was not turned on, but notice that the electrode has been slowly pulled upward until the tip of the electrode comes up onto the carbon rod. At this point the arc will begin on the carbon rod. Once the arc begins, feed it down the carbon rod and onto the steel.
Step 4: The Result
The heat from the welding arc obscurred much of the arrows I drew with the felt tip pen. In this photo you see the beginning of the bead I started and I darkened what was left of the lines again with the felt tip pen, but I did not change their original position.
After a while slag will coat the carbon rod and it will not work as well as it ought. A slip joint plier works well as a tool for scraping the slag from the carbon rod. Just place the rod in the jaws and twist lightly.