How to Make Spot Welds


The Eastwood Spot Weld Gun welds two overlapping steel panels (up to 18 gauge) together using an electric arc to melt the top panel, fusing it to the bottom panel. The two panels must be cleared of all rust, paint, grease, or other material, and must fit tightly together - this is critical to both the strength of the weld and satisfactory results.

Eastwood's Spot Weld Gun uses 60 amps or less, making it possible to weld light-gauge sheet metal (such as auto body panels) with virtually none of the distortion usually caused by high-powered stick welders.

No Assembly Required: Your Eastwood Spot Welder comes completely assembled and includes two heads: one with four prongs for welding flat surfaces and one with two prongs for corners and tight spaces.

Suggested Products For Easier Welding

#19092 Electrodes, Pack of 10
Specially-designed for use with the Eastwood Spot Weld Gun. Carbon-center electrodes provide 60-100 welds each.

#19295 Firepower Fp100 Arc Welder
Perfect welder for the Spot Weld Gun. Requires 120V/20A circuit. Output is adjustable up to 70 Amps. Compact, and portable.

Important Safety Information

Read and understand all instructions before welding. Repair procedures and techniques, tools and parts for servicing motor vehicles, as well as the skill and experience of the individual performing the work vary wildly. It is not possible to anticipate all the conceivable ways or conditions under which a vehicle may be serviced or repaired, nor to provide cautions for all the possible hazards that may result. Standard and accepted safety precautions and equipment should be used during any process that can cause material removal or projectiles, such as cutting, grinding chiseling, prying, etc. Before performing any such operation, you must be completely satisfied that neither your personal safety nor the condition or performance of the vehicle will be compromised.


Welding is a process in which the temperature of metal is raised to the melting point (approximately 3,000º F) so it is important that you work carefully and safely. Here are a few points to make sure that your work will be the best quality you can make it and that it will be done safely.

  • - Wear protective gloves and always use a quality welding helmet.
    Do not use gas welding goggles or other substitutes. Arc welding produces harmful ultraviolet (UV) rays which will damage your eyes and may burn your skin, if not protected. Be sure that others in your work area are protected as well, if they are in sight of the welding arc. Use a good quality welding helmet with at least a #11 lens.
  • - Never work on or near a fuel tank, or near any flammable substance.
    Even when empty, a fuel tank still contains explosive fuel vapors.
  • - Keep a fire extinguisher handy.
    For shop use, your extinguisher should be rated "ABC"
  • - Disconnect the battery and alternator or generator cables if you are welding on the vehicle.
    Since welding uses electricity at high amperage, electrical components on your vehicle may be damaged if the battery cables are left connected.
  • - Never weld in wet or damp conditions.
    Welding uses electricity at high amperage. Be certain the area in which you are working is dry to avoid the possibility of electrocution.

Getting Ready To Weld

Practice, Practice, Practice!

Welding is not a difficult task, but like anything else, there are tricks which you will learn as you do it. The best way to learn is by doing.

When learning to weld, it is important to be comfortable. When welding small pieces, set them up on a non-flammable work surface, and get seated comfortably. Being comfortably seated allows you to look carefully at the welds in progress. It also makes it easier to keep your arms steady.

Practice spot welding on scrap metal to get the feel of the tool and see how it works with your welder. After welding two pieces together, try pulling them apart to check weld strength. The weld should remain on the lower piece of metal when the top piece has been torn off. If the pieces pull apart without ripping, then weld penetration was not sufficient. Try welding for a slightly longer time, but avoid letting the weld burn through both pieces of metal.


  1. 1. Select the correct head and install on the gun.
    Use a slight twisting motion to remove or install heads. The four-prong head is best used on flat surfaces and the two-prong head is best used inside corners and curved areas.
  2. 2. Load the electrode into the tube on the front of gun and lightly tighten set screw.
    Push the electrode into the tube until the tip is even with the head prongs. If you encounter resistance when inserting the electrode, make sure that set screw is loose.
  3. 3. Connect the gun to your welder.
    Insert the end of the gun's power cable into your welder's electrode holder. Be certain that the metal pin on the end of the gun's power cable is in good contact with the electrode holder.
  4. 4. Connect you welder's ground clamp to the workpiece.
    Attach the ground clamp as close as possible to the area which you are about to weld. This will help to speed the welding process.

Making Spot Welds

CAUTION: Disconnect battery ground strap and alternator or generator wires before welding to avoid damaging electrical components.

  1. 1. Make sure that your welder is set no higher than 60 amps.
    Your Spot Weld Gun will work in the range of 40-60 amps. Until you are thoroughly comfortable with this tool and it's capabilities , we recommend starting at a 40 amp setting and turning the amperage up, if needed.
  2. 2. Wear protective welding gloves and helmet with a #11 lens.
    Welding produces both considerable heat and ultraviolet radiation, which can damage your eyes and burn your skin. Proper protection is very important. Also welding heat can travel through the sheet metal, making the surrounding area very hot.
  3. 3. Pull the trigger all the way back and firmly press the pressure head prongs against the workpiece. Slowly release the trigger, until the electrode contacts the workpiece. Current will begin to flow on contact. Immediately pull the trigger up about 1/16" (about the thickness of a dime). This will cause an electric arc between the electrode and the workpiece.

Test Spot Welds

Current will continue to flow, making a crackling sound, as the metal melts and the spot weld is formed. It is very important to watch the spot weld closely as the metal melts and forms a puddle. When the top layer of metal has melted and just as the puddle begins to drop (top layer melting onto the bottom layer), pull the trigger all the way up to lift the electrode away from the workpiece. This breaks the arc and stops the welding process. Continue to hold the spot weld gun against the workpiece for a second, to allow the top layer of molten metal to cool and solidify. You can now move to the next weld.

Let the Spot Weld Gun cool after every 10 to 12 spot welds. Due to the build-up of heat, it is strongly recommended that you let the Spot Weld Gun cool after every 10 or 12 spot welds. Use this cool-off time to check panel alignment and to inspect your work. Overheating will damage the Spot Weld Gun and void the warranty.

Just because a weld looks good doesn't mean that its a good weld. A good weld must penetrate through the top layer of metal onto the bottom layer. An ugly weld with a good penetration is better than a good-looking weld with little penetration.

When spot welding, closely watch the puddle which forms beneath the electrode tip. The puddle on the top layer of metal should melt and drop onto the bottom piece. Break the arc by pulling the spot weld gun's trigger all the way up just as this happens.

The key to a good spot weld is to get enough penetration through to the bottom layer so the top and bottom pieces will hold together. This is a function of time (how long you hold the arc) and the thickness of the sheet metal, which will vary from car to car and even location to location on the same car. For example, most fenders are a thinner gauge metal than floorboards. Most older cars use thicker metal than newer cars and most imports use thinner metal than domestic cars.

Experiment on some scrap panels the same thickness as the panels on which you will be working. Remember: holding the arc too long will burn pinholes through the metal and not holding it long enough will produce weak welds.

To test practice your spot welds, clamp the test piece solidly in a vise. Try to peal one panel from the other. It is usually possible to separate the panels, but a good spot weld will rip out of the top panel and the spot weld "button" will remain firmly attached to the bottom panel.

Practice until your spot weld can stand up to this test over and over again before going on to your project.


NOTE: Never allow the electrode to glow more than 1/2 inch above the tip which can overheat the gun. Repeated overheating of the electrode can lead to failure of the Spot Weld Gun's components and will void the warranty.

Poor Electrical Contact: There may be too much resistance between the welding clamp and the work area. Make certain the welder's ground clamp is attached to clean, bare metal as close as possible to your work area.

Welder Amperage Set Too Low: Try increasing your welder's amperage in small steps, do not exceed 60 amps.

The Top Layer Melts, But Does Not Adhere to the Bottom Layer: There is probably a gap or space between the layers of the workpiece - make sure both layers are clean and clamped together firmly.

Both Layers of Metal Melt, Resulting in a Hole in the Workpiece: The amperage on your welder is set too high or you are holding the arc too long. Your Eastwood Spot Weld Gun is designed to work between 40 and 60 amps. The amperage setting on many spot welders may be inaccurate, so start off at 40 amp setting and increase it to 60 amps only if the 40 amp setting proves insufficient.

NOTE: Use only electrodes designed for this unit. Eastwood supplies replacement electrodes (Item-no# 19092) which have the proper makeup for the most efficient operation of your Spot Weld Gun.

Other Suggested Products

#19074 Panel Holding System
Holds panels in alignment while welding. Includes 2 side holders, 10 blind holders, and special removal/installation tool.

#31018 Combination Hole Punch Flanger

Professional-looking repairs with less filler. One side flangers metal for patch-panel replacement. The other side punches 3/16" diameter holes for plug welding.

#31042 Anti Heat Compound

Anti-Heat Compound absorbs excess surface heat. Spread it on with a putty knife to a 3/8" thickness as close to the weld or solder area as possible. This confines the heat to the open area. Great for applications close to windows and rubber/plastic seals.

#19045 Eastwood Stitch Welder

Faster and easier than stick welding, the Eastwood Stitch Welder is super for joining patch panels. Welds steel from 22 to 18 gauge. Works great with the Firepower Fp100 Arc Welder (#19295).