Using A Stud Welder

 Stud Welders

The stud welder is used to weld a small steel pin (stud) to a dent in a steel body panel. Then a slide hammer is used to hammer the stud outward.  A proper electrical connection is essential to get a good weld.  Use of an inferior cord will cause a “cold weld,” causing warping or the pins to have a poor attachment.  If you use an extension cord, it is imperative that it be at least a 14 gauge three-conductor wire and no longer than 25 feet long.  The outlet should be a minimum 15 amps and a dedicated line (don’t have several electrical items pulling electricity off of the same connection). To start, grind the lowest part of the dent to produce a clean bare metal “bright finish.”  The dented area needs to be bare metal, all the paint must be removed around the stud location.  The bare metal spot needs to be at least the size of a quarter, perhaps bigger for good heat conduction.  When the trigger of the stud gun (welder) is squeezed, electric current flows though the stud pin and fuses the stud to the car body. Insert the pin and press firmly for a ½ second to 1 second.  A proper weld will discolor the metal approximately 1/8 to ¼ inch around the stud rivet.  Once this is done, let the metal cool, and then do the dent pulling. To shrink an “oilcan” or low spot on the surface, apply heat with the shrinking tip.  Depress the trigger for ½ second while using a spiral motion, starting on the outside of the low spot moving towards the center.  Next apply a cold compress to shrink the steel back.  To remove a “high spot” on the surface, place tip directly on the top of the spot and heat for ½ second.  If heat does not totally remove the high spot, hammer gently while still warm. For safety, be sure to read your stud welder manual.

 

This is an electric stud welding gun.

This tool is used to weld a small steel pin (or stud) to a dent in a steel body panel. Then a special pull-hammer is used to hammer the stud outward.

 

These studs are about 1½ inches long. 

 

 

To begin, the stud is inserted into the end of the gun.

The outer copper ring is negative and the center copper nipple is positively charged. When the trigger is pulled these metal parts are energized.

Of course, this tool needs to be pushed up against the bare steel for anything to happen.

 

To use the stud gun, the tip is pressed against the bare steel. When the trigger is squeezed, electric current flows through the tip and fuses the stud to the car body.

The dented area needs to be bare metal... all the paint must be removed around the stud location. The bare metal spot needs to be at least the size of a quarter, perhaps bigger.

 

 

Once the stud is attached to the car body, the stud welder gun is pulled away, leaving the metal rod attached to the car.

 

Some dents can benefit from multiple studs. It's best to install all of the desired studs, let the metal cool, and then do the dent pulling. Since this dent was a long skinny crease about 4 inches long, 4 studs were attached, about an inch apart.

 

After all the dent pulling is done, cut off the studs with a pair of wire cutters and then use a grinder to grind down the remaining bit of steel.

 

Finishing Touches:

Once the dent had been pounded outward, apply a thin coating of plastic filler (a.k.a. Bondo).
When the filler is hard sand the area smooth and level, then prime and paint the entire area that needs to be repaired.