MIG Gun consumables and the liner play a significant role in gun performance and weld quality. MIG Gun Liners. This might be a new term for those who have just started out with welding or haven’t gathered enough information about your MIG welding gun.
Well, we are here to get you all the required knowledge about these MIG liners. Being very simple to install and execute, this is one of the most influential components of a MIG gun.
A MIG gun liner is either a tube or helically wound wire which acts as a conduit to guide the welding through the MIG gun to the contact tip. The sole role that it plays is to feed the welding wire from the wire feeder to the contact tip via the gun cable.
This significantly affects your gun performance and weld quality. Proactive maintenance is required to optimize the weld performance and reduce operator downtime and rework too.
General feeding problems are known by erratic wire feeding, wire burn-back, and bird-nesting too. Most of the causes of these issues are incorrect drive rolls, clogged liners, improper installation of wire liner, and other liner issues.
Types of MIG gun liners for a welding job
MIG welding liners are divided into several types based on the semi-automatic and robotic applications in the welding industry. Based on personal preference and maintenance possibilities, one can choose the type of liners. The basic three types of liners are – conventional liners, front-loading liners, and spring-loaded front-loading liners.
These gun liners are installed through the back of the gun. They are used in MIG welding units which have only industrial uses. The changeover is a lengthy and tedious process. The cable keeps growing and shrinking with more and more twisting.
These MIG gun liners are installed in the front of the gun. It reduces downtime and helps provide more time-saving advantages. Here the wire does not grow or shrink as the cable begins twisting.
Front-loading liners with a spring-loaded module:
Allows more than 1 inch of the motion of the cable twists and more. If you can trim the liner properly, it can be more forgiving than being incorrect.
Plastic MIG gun liners
There are a bunch of plastic MIG gun liners which are quite inexpensive and more popular among welders than steel or other metallic gun liners. Each type of plastic used makes the liner durable and a better fit for certain types of filler metal. They are as follows:
This is a carbon-filled nylon liner that can be used only in low temperatures and for low-duty air-cooled with a large amount of versatility. It can be used for push-pull operations of smaller gauge aluminum, stainless steel, and silicon-bronze welding wires.
It has a bronze spiral-wound liner attached to the front-end which enables us to use the MIG gun at very high temperatures. The brass jumper also allows a better flow of current and low-melting-point liners to be used in high amperage duty cycles.
These MIG gun liners are made for being used with soft wires and those having poor column strength like aluminum, bronze, and 4000 series aluminum. These liners have smooth interiors and provide stable wire feeding. Polyethylene has a low melting point.
Teflon has a higher melting point than Polyethylene and is ideal to be used in high-temperature applications that have a water-cooled torch and have brass neck liners. Teflon is abrasion-resistant and is can be used for a variety of wires.
Carbon Teflon (CTFE):
These MIG gun liners are suitable for stainless steel applications (ER308, ER309, ER409cb) and so on. It has good temperature and abrasion resistance when compared to other plastic liners.
High-Density Teflon (HD-PTFE):
These liners have a similar melting point as that of carbon Teflon liners providing long lifetime service and efficiency. These liners are compatible with wires ranging from soft to stiff wires.
What are ‘Neck-liners’?
Neck liners are some specially designed tools that extend the life of our wire liners. They are also known as ‘Jump-liners’ and have a small collet that sits in the welding torch itself and is very easy to be replaced if so needed.
The most common issue comes with the failure at the gun’s neck and this can be the best way to save your time. Moreover, using a neck-liner is ecological-friendly and hence is cost-efficient. It is important to match the neck liner size to the wire we use because the neck liner material should be a good fit for the wire.
Installing a MIG gun liner
Replacing the MIG gun liner: (Miller)
Cut, Fit, and Install a New Liner:
Tips to Optimize MIG liner installation:
How does a MIG welding liner become dirty?
Being ignorant and unaware of how your MIG liner is working and getting affected over time will cause a lot of damage to your liner affecting your weld performance and damage to your entire career. Being proactive and considerate at all times can save you a lot of maintenance and repair costs and also save you some useful time.
Liners must be maintained in such a way that they are flexible and rigid at the same time. Bending the cable too much can lead to problems like poor wire feeds, bird-nesting, and dirty liners. Tight bends between the wires increase the friction between the edges and increase the tension to bring the liner out of the gun.
This in turn causes the accumulation of metal fragments in your liner and causes some unintentional and hazardous wear and tear. This happens regularly can cause large debris to be formed in the wire feed causing blockage and poor performance rate.
Make sure your cable/wire after cutting is formed in a straight line. Because if it is found to be curved and twisted, it may cause a shortage of liner causing the liner to have more spaces and unwanted gaps making it viable to a lot of dirt and debris.
How do you clean a MIG welding liner?
Sean Coby is a welder par excellence and well respected among the welding community in Woodbridge, VA. He prides himself to be the fabricator and mechanic in the automotive/ diesel industry for the past more than eight years now. As the chief editor of his https://weldinginfocenter.com, he shares his experience to be safe during welding and to take proactive steps for becoming a successful welder like him.