These stamped steel ground clamps are standard from the factory on many welders. They work pretty well, but performance degrades in time. I could buy a nice brass ground clamp, but would rather just improve the contact and current path on this clamp.
Step 1: Fit a piece of aluminum bar stock
I decided to fit some aluminum bar stock inside one half of the stamped steel spring clamp. My bar stock is 1/8 inch x 3/4 inch. The space inside the stamped steel clamp handle is about 9/16 inch. I used a hacksaw to trim off the excess.
Step 2: Drill a hole in the aluminum
Drill a hole through the piece of aluminum for the cable bolt.
Step 3: Cut and bend the aluminum piece
In this photo I have drilled out and removed the rivet that holds the clamp together, removed the plastic handle grip, loosened the bolt, removed the cable, cut the piece of aluminum to length, and bent it to fit the contours of the stamped piece of steel.
Step 4: Build up the thickness
I cut a second piece of aluminum to thicken it inside the jaws so it can clamp directly against the steel I am welding.
Step 5: Drill for a brass screw
I drilled through both pieces of aluminum at the jaw and the steel of the jaw, used a countersink to prepare the aluminum for a bevel head brass screw, inserted the screw and fastened it with a brass nut. I cut the brass screw end nearly flush with the nut and peened it with a hammer to keep it from coming loose in the future.
Step 6: Inserting the spring
The spring is quite strong. I did not want to wrestle it back into the handle halves while trying to insert a screw to replace the rivet. I decided to squeeze the spring in my vise and tie it in its squeezed position with some sturdy wire.