Posted on Nov 20, 2020
A question we get asked often is “How do I select the right Mig gun?”. With so many different ratings, specialities, designs and types, it can be confusing. We touched on this briefly in our Mig Welding Questions answered post, and today we are going to go into a bit more detail.
Where To Start
It’s important to understand how exactly your operators will be welding – the applications and how frequently they will need to be welding. Is it a few minutes here and there, or is it sustained consistent activity?
The Amperage Question
It is often thought that bigger is better, and so welders use guns at a higher amperage than their application requires “just to be safe”. In reality, this is often unnecessary. For example, you may purchase a 300A Mig gun when the majority of your applications only require 275A. However, most operators are realistically only welding for a maximum of 50% of their time. Therefore a lower amperage gun with a rating of 200-250 Amps could very easily handle the demands without exceeding the duty cycle in even a 275 Amperage application. In this scenario, the higher amperage welding gun is not going to perform any better than the lower amperage. So, why not opt for the smaller gun.
Another key point is that although a Mig gun may be called, for example, a 350A, it could very well have a different duty cycle from another brand of 350A gun. So, it is always worth comparing duty cycle between models – you may find that the lower amperage gun easily meets your needs.
And That Leads Us On To Size
Generally the higher the amperage, the larger the Mig gun. Larger guns are heavier, bulky and less manoeuvrable. So it’s an important consideration, especially as this increased size leads to increased operator discomfort and fatigue and therefore has a knock-on effect on productivity.
While it might not always be your first consideration, the weight of a torch is important, particularly when considering the impact of static load on the body. Static load, or static effort, occurs when muscles are kept still and tense, for example when welding. Holding the arm elevated or extended in any direction for any period of time, which increases pressure on muscles, tissues, tendons and ligaments, as well as reducing blood flow. Awkward positions (for example welding in small gaps or at difficult angles) can also increase static load.
Static load also leads to fatigue at a much quicker rate, plus recovery takes up to 10 times longer than from more dynamic work. So, it is clear that weight matters, not just because it makes the job a little bit harder, but also because it has a very real impact on the health of the operator.
While some static load is unavoidable, additional weight worsens the effects, and so weight and comfort is really something that should be a major factor. It is also important to note when selecting your Mig gun if you do need to go for a high amperage torch, that different brands vary in weight, so a 400A Mig gun in one style may be heavier and bulkier than another. Plus some designs such as our Suregrip BZL range [LINK] feature an ergonomic shape, enabling the welder to keep hold of the gun without having to grip tightly, further reducing static effort.
Know Your Angles
Welding in uncomfortable angles for long periods of time will increase the static load on muscles, so positioning the job to make the work as easily accessible and comfortable as possible is important before you even start welding.
Smaller, lighter torches are inherently more manoeuvrable, and there are a whole host of clever features designed to make guns more ergonomic. Our Mig guns feature a knuckle joint where the cable and handle join enabling movement of the torch independent of the cable, making them much more flexible.
Use the right consumables for the job
Selecting the right consumables is a whole other topic, but there are a wide range of different types, with designs to make specific tasks easier, for example improving visibility or access.
Overall, it is important to understand the needs of the welders and the task at hand in order to select the right Mig gun. Keeping operators comfortable is key to maximizing productivity, and by selecting the right Mig gun for the job you can ensure that you are getting the best possible performance.
At Parker Torchology we offer a wide range of different styles and amperages of Mig guns, all carefully designed to ensure maximum comfort and productivity. View our Mig Range