Metalworking offers challenges every day. There are times when a fabricator might need to grind a rough weld, remove casting marks, chamfer or even round in small or tight spaces – all in one day. With the right tools and accessories and a little elbow grease, they can effectively remove excess weld material or create a seamless transition to get the job done right.
Different applications and the level of finishing the user requires determine which tool and abrasives are the best matches for the projects fabricators are working on. They may need to use a flat head angle grinder or fillet weld grinder/finisher to reach far and narrow spaces. Perhaps they need to grind in small angles or square places, so a band file may be the best bet. Maybe it’s just a matter of removing sharp burrs in a tight spot where a die grinder can easily do the job.
So, which tool should be used? While it depends on the application, there’s more to it than just pinpointing a certain tool. The process can become complicated once the many variations of each tool are presented. Understanding the options, however, can reduce the challenge of knowing what to use and when.
Angle and fillet options
As an example, flat head angle grinders come in a variety of styles. There are many choices based on power or paddle switch versus lock-on switch. There is a flat head angle grinder for every level of need, anywhere from a straightforward compact version to more power for quick removal or a flat head angle grinder with unique safety features. There is even one specifically designed to process stainless steel.
Overall, a flat head angle grinder can get into a long narrow space as tight as 2 5/8 in. high or 39 degrees. When it comes to producing a smooth, finished weld in a tight angled area, it’s the quickest approach.
Metabo offers a variety of compact 5-in. flat head angle grinders. Just as a range of models are available, a range of abrasive types can be used with flat head angle grinders. For example, there are specialty curved convex wheels for heat-sensitive materials for precise cleaning and for uniform finishing of weld seams as well as grinding wheels, cutting wheels and knotted wire wheels.
Fillet weld grinder/finishers are similar to a flat head grinder in that they can fit into long narrow spaces. The most noticeable difference between the two is a fillet weld grinder/finisher that has an extended neck and head that can be swiveled without the use of tools. This tool is used to clean the most common type of weld, a fillet weld, sometimes also known as a T joint.
Fillet weld grinders are well-suited for difficult-to-reach welding seams. And, they are also good for working around weld seams on pipes or even stainless steel stairs and railings, providing a larger radius to maneuver.
When it comes to accessories, unitized abrasive wheels clean and polish fillet welds. These wheels are made of compressed nylon on a fiberglass disc, specifically created to handle deburring and finishing applications, significantly reducing the number of working stages required.
Die grinders and files
Die grinders are perfect for smaller, more targeted areas that the user might want to smooth out, chamfer or round. They are also ideal for working the inside or outside of a pipe for weld preparation. Accessories that allow for even greater flexibility when working with this tool include a flexible shaft that allows the user to work inside narrow pipes where a regular die grinder may not be able to fit.
Similar to flat head angle grinders, Metabo offers a large variety of die grinder configurations. Besides the type of switch, the difference in power choice will depend on the application and material with which the user will be working. Variable-speed die grinders also allow all kinds of materials to be worked – from plastic and glass to hard metals. Lower settings allow more accurate grinding, as well.
Although a band file, with its flat rotating band abrasive, might sound like a simple tool, it’s essentially a mini belt sander that can step in when a grinder is too big.
Typically, band files are useful for deburring, burnishing and grinding down weld beads or spot welds quickly and easily. They’re also helpful at getting into square-shaped pipe for cleaning. Band files work well on internal and external surfaces. Metabo’s band files have a head that swivels 270 degrees and can be changed without any tools, making it not only easy to use but ergonomic for the user.
The sanding belt width on these tools ranges from 1/4 in. to 3/4 in., allowing the band file access to the tightest locations while avoiding damaging adjacent work areas. A band file is a must-have tool for anyone that welds or does weld clean up in close spaces and wants to get a more even finish.
A variety of accessories can be used with flat head grinders, fillet weld grinder/finishers, die grinders and mini belt sanders – a tool for every stage of the finishing process. When choosing an accessory, pairing Metabo accessories with Metabo tools optimizes output. Metabo accessories are specifically designed to fit their counterpart power tools seamlessly.
Tool safety features
When it comes to safety, grinding metal presents its own challenges, but using the proper power tools and accessories can help eliminate some concerns. In that regard, Metabo developed a variety of safety features that help manage and control the tool while protecting the user and extending the life of the tool, as well.
As an example, a safety clutch and brake combined with soft-start overload protection and paddle switches enhance operator safety and reduce the risk and severity of injuries.
Metabo flat head angle grinders and fillet weld grinder/finishers also come with a wealth of safety features. These tools have a VibraTech handle, which can reduce hand/arm vibration by up to 60 percent while increasing tool life considerably.
The flat head grinders have a tool-less adjustable burst-proof guard with seven stops, and the WEPBF flat head grinder in particular includes a mechanical safety brake that stops the grinding wheel from spinning in less than 2 sec. or stops thin cutting wheels in 1 sec., significantly reducing the likelihood of injuries.
Most of Metabo’s die grinders are equipped with power interruption protection, electronic overload protection and soft startup. There are also choices such as a non-locking paddle or a slide-locking switch, depending on the user’s preference. For something more durable than a flap wheel, carbide burrs are a good option. Carbide burrs are great for smoothing rough steel or aluminum edges over smaller surfaces, and they will last a long time without breaking or chipping.
Finally, band files have detachable dust filters that protect the motor from coarse particles. Overload protection is also available to keep the motor from overheating. Electronic soft start delivers better control and ease into the work. Metabo band files include restart protection, preventing unintentional startup if the power source is interrupted.
Outside of general power tool safety, fabricators should always wear proper PPE when working with power tools. This includes protective clothing and gear, such as safety glasses, a face shield (or both) as well as gloves and hearing protection.
If the worker is uncertain of what PPE rules they need to follow, they should check with their employer for requirements. Metabo also offers free power tool safety training to its customers with the company’s mobile safety training/jobsite trailers.