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Best Angle Grinder for Welding

Best Angle Grinder for Welding

Angle grinders are powerful hand tools that you can do a lot of work with. They are some of the most versatile hand tools for construction work and fabrication shops and they also come in many sizes. I know many of us have already seen or use or even own your angle grinders. But did you know that certain angle grinders are best for certain jobs especially for welding jobs

Here we would be discussing which size is the best angle grinder for welding that could offer you a lot of variety on your metalworking shop. 

As we know, a grinder for welding can be very useful for removing rust, smoothing out welds, grinding grooves, polishing metalwork, and for cutting thin and thick metal. So regardless if you’ll be doing MIG welding or TIG welding, once you start doing your welding project up until you’ll be finishing it, the angle grinder can be used as a preparatory and finishing tool for your project. With its detachable consumable discs, this handy implement can be one of our most reliable tools as a welder.  

Take note that the cutting or grinding replacement discs between metal and masonry are not of the same materials and elements. Consumable discs for metal are made of reinforced abrasive materials while for stone are generally the diamond cutting discs. So which grinder size is best adapted for welding job?

angle grinder size

Available Sizes of Grinders for Welding

There are 5 different sizes for angle grinders and these are the 4½ inch (115mm), 5-inch (125mm), 6 inch (150mm), 7-inch (180mm), and the 9-inch (230mm). Their wattage range from 500 to 2500 watts. The larger the angle grinder, the more wattage the grinder needs and the more it becomes more powerful. But the most common among these are only three and these are the 4.5, 7 and the 9-inch. 

Remember that the size of the grinder is not determined by its length but by the size of the discs it can handle. So if you are looking for the best angle grinder for welding your choice should be based on how you use it, where you use it, and how you can handle it. Obviously, the bigger the angle grinder, the bigger discs it can accommodate and the more powerful the tool can be.

 For every size, there is also certain voltage, wattage and amp ratings and their amp range from 4 to 15. So how would you know which size is better for your welding tasks?

angle grinder
welding bevel
Best Angle Grinder for Welding

The 4.5-Inch Angle Grinder

Experts agree that an angle driver that is more than 7 inches is already considered a large grinder while smaller than 7-inch is seen as a small type grinder. So significantly, the 4.5-inch angle grinder should be a sleek, handy grinder that you can use for light to medium size work. These include grinding, polishing and all other things that the best angle grinder for welding should perform on a light work basis.  So what is the advantage of a small grinder compared to its larger counterparts?

 The 4.5 angle grinder is the best option when it comes to polishing flat metal with narrow surfaces and narrow edges. They are also perfect for cutting on thin metal sheets, cutting up bars up to 2-inch in diameter and refining rough edges made my plasma cutting on thinner metal. 


Because of its handiness, lightweight, and slimmer feature, the 4.5-inch grinder is the favorite grinder for welding for small grinding, smoothing and polishing work. If you are a DIY guy, have a welding shop or home workshop or have small metal projects from time to time, such size could provide you a lot of conveniences. 

You can also use a 4.5-inch angle grinder for home renovations projects like polishing your stainless furniture if you don’t have a buffer polisher. Since you can load a lot of different discs on your small angle grinder while providing you the greatest maneuverability, you can do a lot of things with this size. 

Remember that small angle grinders spin aggressively faster than the larger grinders so don’t use them as polishers for things that are painted such as your cars or bikes. Despite its size, this can load up to 10000 rpm and thus perfect for removing rust, old paint and smoothing out rough surfaces and edges on any metal. 

So if you want to keep the best angle grinder for welding in your home, this size is much more convenient and lighter to use.

The 7-Inch Angle Grinder

This size is already in the heavy-duty but medium-size category. Bigger than the 4.5-inch angle grinder, you can benefit from it if you are working on construction sites where cutting and welding metals are involved. 

The 7-inch angle grinders are also available in various amp ratings and wattage. They are a bit slower than the handy 4.5-inch and could afford up to 8000 rpm. 

Yet, even though they are  not blazing fast spinners, they can cut through thicker metals like 2-inch tubing or flat bars. Such thickness using a small grinder requires that you have to turn the other side of the metal to cut the metal completely while making it difficult to get a straight cut. 

The 7-inch angle grinder can be your best angle grinder for welding if you are running a repair shop, an auto shop, working on metal outside your home or dealing with larger types of metal that need cutting, polishing, smoothing out edges, removing paint or dirt and a lot more. 

And because they are more heavy-duty than the small grinders, they can also last longer considering that you know how to take care of them. 

On the other hand, you can also keep the 7-inch in your garage if you want to get things done much faster especially on bigger grinding work.


The 9-Inch Angle Grinder

If you are into professional metalwork and you frequently need a large, heavy-duty and powerful manual grinding machine, this calls for the use of a 9-inch angle grinder. 

Such size could work well either for heavy concrete jobs or for massive metal grinding work. Yes, the 9-inch angle grinder could be as heavy as 10 pounds that it can hurt your shoulder and arms using it the whole day. But with such a large machine and powerful tool that can pack up to 2000 watts and up to 15 watts of power, it can be the best choice for professional welders, metal fabricators and construction workers. 

Because of the power that it is loaded with, this heavy-duty tool can clean out, de-rust, polish and grind wide surfaced metal in a shorter time. If you are willing to save a lot of manual work hours to your work, you better opt for this type. 

For example, if you had cut a wide sheet of metal about 1.5-inch thick using a plasma cutter that leaves large rough and jagged edges on the cut, the quickest way to smooth up these edges is by using a heavy-duty, large angle grinder like the 9-inch type. And yes, this can deal with the toughest metal. 

With its large disc features and offering a variety of disc consumables for any type of grinding tasks, this should fit your need for heavy-duty work.


angle grinder hire

Choosing the best angle grinder for welding can be quite difficult if you are not sure what size you need for your work. So try to remember that if you only need a handy grinding tool for your home and doing small grinding projects, you don’t need to go far and would prefer for the 4.5-inch size (small). 

However, if you have to deal with larger and bigger metals whether you need to work outside your home or work on metal fabrications or construction sites, it’s either you choose between the 7-inch (medium) or the 9-inch (large) type. So your choice will  largely depend on your need for a grinder that can provide you the versatility, capability, power and handiness you need for your projects.