Using spool gun to weld thin or aluminum materials is becoming more and more popular. More and more mig machines on the market support spool gun, which has gradually become the standard configuration of mig welder. A spool gun is a hand-held device that feeds a small spool of welding wire directly into the weld joint. This technique is ideal for welding thin materials or aluminum.
Using a spool gun in your welding projects can be challenging, especially if you are a beginner. However, with the right techniques and tips, you can improve your welding skills and achieve excellent results. In this article, we will discuss some tips for using a spool gun in your welding projects.
Spool gun is a combination of MIG welding gun and wire spool with small motor which are compacted in one tool called spool gun. This tool is mainly designed for welding soft wires like aluminum welding to decrease welding wire kinks that may happen during welding using traditional welding gun. In addition to aluminum welding, the spool gun can be used also for stainless steel and mild steel welding. In this blog we will go deeply into explaining the important issues to be taken into consideration during welding using spool gun.
Are spool guns standardized?
Till now, each manufacturer has his own standard spool gun that has become compatible with his MIG welding machines but may or may not compatible with other welding machines of other manufacturers. So, before buying your spool gun, be sure that the spool gun is compatible with your welding machine.
How to install your welding spool gun?
- The welding torch connects to the welding power source torch euro fitting, the wire feed on the welding machine should be disabled to stop wire being pushed into the spool on gun torch. The electronic module (part of the torch lead near the euro connector) has a single pole black socket fitted which needs a connection the welding earth (negative). This connection can be made using the 4mm plug or simply a wire under the screw. The wire can be attached directly to the work piece or welding clamp or directly onto the negative output socket on the power source, this can even be an unused inductance terminal etc.
- A spool of wire can now be fitted to the torch; the end of the wire must be straight and must be guided through the tube and through the rollers, which are lifted by pressing down the red knob near the spool. The rollers can be accessed by carefully removing the clear plastic cover with a screwdriver but this is not normally needed unless the rollers are to be changed. The roller pressure is adjustable by a screw in a recess just in front of the red knob, this must be set up to give optimum wire feeding, (turn anticlockwise to increase pressure).
- There is an adjustable break to stop over run of the wire spool and snags that normally follow, this break is adjusted by the screw in the center of the spool and should be set to give enough braking to stop the reel at the finish of a weld and not over run, do not set too tight. The position of the spool can be changed by loosening slightly the Allen head screw near the rollers, after turning to position re-tighten the screw gently.
- Welding can now be carried out using the torch like a conventional MIG torch, the speed of the wire is set by the knob on the bottom of the torch, welding voltage is set on the welding power source as normal. Adjust the rollers pressure if necessary to make sure the feed is consistent and not slipping, do not increase pressure too much otherwise there will be unnecessary wear of drive parts etc.
What are the main settings when using spool guns?
There are some of few factors that should be taken into consideration when starting welding by using spool gun:
- Voltage and wire feed speed: voltage and wire feed speed adjustments are the first step when using spool guns to avoid excessive spatters in case of using higher voltages and to avoid un stable arcs in case of using lower voltages.
- Filler metal and shielding gas selection: you have to select the proper filler metal that fit to the base metal in addition to selecting the proper shielding gas with the suitable flow rate where in case of using higher flow rates, the weld will cool down and it became difficult to get a stable rigid arc. The purity of shielding gases is very important to have sound welds, so keep in mind to deal with known and licensed buyers and to get shielding gases with certifications showing purity and quality.
- Stick out distance: you have to select the proper stick out distance to avoid stuttering arc that may result from using short stick out or improper wire feeding speed and also the proper stick out will keep your torch tip clean from any weld metal that may happen due to burn back of welding filler wire.
You have to keep your eyes open to adjust your settings of MIG welder continuously to keep your arc stable and rigid.
What are the main problems with using spool guns in welding?
Spools guns have some problems however they are problem-free wire feeding, especially for the soft filler wires like aluminum. These problems include:
- Weight of spool gun: in manual welding, the weld torch is hand-held which become heavy on the welder during welding resulting in un comfortable experience due to muscle stain and some times injuries.
- Accessibility: the large size of spool guns especially with the T shape hinder the welder from reaching some points during welding.
- Maintenance: the spool guns are liable to drop at site many times as usual with welders but in our case (spool guns), the drop will cause damage to spool rollers which become difficult to maintain and if maintained, it will cost more than the traditional welding guns.
The important Tips You should know
Choose the Right Spool Gun for Your Welder
One of the essential things to consider when using a spool gun is choosing the right one for your welder. Spool guns come in different sizes and specifications, so it's essential to choose the one that matches your welder's specifications. Make sure to check the manufacturer's recommendations for your welder and choose a spool gun that matches the wire feed speed and voltage requirements.
Select the Right Wire Size
Choosing the right wire size is critical for achieving excellent welding results. When using a spool gun, it's essential to choose the correct wire size for the material you are welding. If the wire is too thick or too thin, it can affect the weld quality and create a weak joint. Check the manufacturer's recommendations for the wire size and type that matches the material you are welding.
Keep the Welding Area Clean
Before you start welding, it's crucial to properly prepare the welding area. Clean the area to remove any dirt, debris, or oil that may affect the weld quality. Use a wire brush or sandpaper to clean the area and ensure that the joint is properly fit. Proper preparation of the welding area will ensure that the spool gun's wire feed is smooth and uninterrupted.
Adjust the Wire Speed and Voltage
The wire feed speed and voltage are two critical parameters that affect the weld quality when using a spool gun. The wire feed speed controls the amount of wire that feeds into the weld joint, while the voltage controls the heat generated by the welder. Adjusting the wire feed speed and voltage can help you achieve the correct penetration and prevent burn-through.
Use the Correct Technique
Using the correct welding technique is essential for achieving a strong and durable weld joint. When using a spool gun, it's essential to maintain a consistent travel speed and keep the spool gun at a consistent angle. The recommended angle is usually between 10 and 15 degrees. Use a push or drag technique, depending on the material you are welding.
Use the Right Shielding Gas
The shielding gas is an essential component of the welding process. It helps protect the weld pool from atmospheric contamination and improves the weld quality. When using a spool gun, it's crucial to use the correct shielding gas for the material you are welding. Argon or a mixture of argon and helium is usually recommended for aluminum welding.
Conclusion
Spool gun is the proper solution to avoid wire feeding issues which essentially happen with soft filler wire like in aluminum welding but this tool has some draw backs to be taken into consideration that is why you can get the best result by optimizing all of the above factors and adjust your gun to fit to all the required welds.