Angle Grinders Safety Tips: Sometimes the only tool in your arsenal that will make the cut for the job is the angle grinder. It’s a very versatile tool used in woodworking, masonry and metalworking. Its main uses include cutting, sanding, polishing, and grinding down surfaces to a smooth finish. It is, however, one of the most dangerous tools in your workshop and should be treated with utmost care.

We will look at some angle grinder basics, as well as which discs are best suited for which job, and present you with tool hacks and tips that really reinvent the wheel.

Angle Grinders: Tool & Safety Tips


1. Size and power

Size matters when it comes to grinders – the larger the disc, the more powerful the motor will be. Angle grinder discs come in various sizes. The most popular ones range between 4 and 9 inches (approximately 11 – 22 cm). There are several factors to consider when selecting the appropriate size grinder. 

Small Angle Grinders

Angle grinders that take disc sizes of 7 inches or less would fall into this category. If portability and manoeuvrability are top priorities, then small is the way to go. In addition, smaller discs spin faster, making them ideal for cutting and polishing metal. A downside, however, is that smaller discs also tend to overheat much easier.

Generally, a disc with a 4.5-inch diameter will be sufficient for most workshop projects. Angle grinders on the small end of the scale come in various power supply options: corded, cordless and pneumatic.

Medium and Large Angle Grinders

Designed for deep cuts and larger surfaces, these grinders have more powerful engines – generally kicking out 3 horsepower and more! In addition, medium-sized grinders take 7-inch discs, whereas 8 – 9 inches are considered large.

2. Interchangeability

When buying an angle grinder, choose a model that allows for changing between discs, attachments and accessories.

3. Adjustable Guard

Make sure the model you buy has an adjustable guard – this will protect you by deflecting sparks and debris. ALWAYS and ONLY use your angle grinder with the correct guard supplied by the manufacturer.

Angle Grinders: Tool & Safety Tips


Before you begin:

  • Ensure you have all the correct protective workwear at your disposal. This will include Earplugs and Earmuffs, Class 5 Cutting Gloves, Dust Mask, Grinding Face Shield and Safety Goggles. You will also need Clothing that is not easily flammable and strong Safety Boots.
  • IMPORTANT: Never substitute a Grinding Face Shield for a Welder’s Mask, as it obstructs too much visibility and can be a safety hazard.
  • Ensure your work area is safe. Grinding causes sparks, so don’t grind in a flammable area. Always ensure there is a fire extinguisher present close to a workshop exit. Keep a well-stocked comprehensive First Aid Kit close by.
  • Always read the manufacturer’s operation and safety manual before you work with a new tool.
  • Test your grip on the grinder handle and the tool. Give the handle and grinding wheel nut one last securing twist to ensure everything is secure before the grinder is plugged in.
  • Always allow the grinder to reach full speed before applying it to the work area. This not only maintains the motor mechanism of the tool but also prevents kickbacks and serious injuries.

During the duty:

  • Always ensure you are using the correct disc for the intended application. Cutting discs for cutting and grinding discs for grinding. Mixing these up can result in disc deterioration and instant injury.
  • You must only fit the right-sized disc with a hole that matches the spindle flange of your grinder.
  • Always orient the work, so the sparks and debris shooting off the disc are directed downward and away from you. The disc should always spin away from sharp corners and not into them. This prevents the disc from kicking back and causing injury.
  • Always cut in a straight line, and don’t change direction while cutting. Only jigsaws can do this safely, and an angle grinder was not made to be used in this way.
  • Try to keep the grinding position on the wheel at “12 o’clock” for the best results. Try to steer clear of positioning yourself directly behind the grinder during work. You’re doing it wrong if you need to put too much pressure on the grinder to achieve the result. Never grind something on the floor between your legs, as this is an extremely unsafe position.

When the job is done:

  • Been cutting or grinding aluminium? It’s best to bin the disc after the job is done. The disc surface is compromised, and the aluminium residue is left behind on the disc’s surface. So, if you happen to use that disc again on an even slightly rusty surface, an instant dangerous chemical reaction between the rust, aluminium and heat will form a highly flammable substance called Thermate which will burn your whole workshop down.
  • Always unplug the grinder if you are not using it, changing discs or modifying anything on the grinder during work.
  • Always store the grinder in a safe place out of reach of children, with the cord safely tucked away.
  • Ensure damaged discs are thrown out and recycled – and NOT re-used.


  • Always check your disc for its maximum revolutions. The max indicated on the disc must always be higher than the max indicated on the grinder. This prevents disc breakage or potential injury.
  • Always ensure you have fastened the grinding wheel nut correctly. Some discs will require the nut to have the raised side down to fit the disc hole snugly, and others will need the nut to have the recessed side down. Always make sure the disc is adequately fastened before plugging in the grinder.
  • Several modifiable and purchase-ready attachments are available for angle grinders. These range from belt-sanding attachments to mini chainsaw attachments & more (Always consult your model of grinder’s manual).
  • Don’t let your project materials grind you down. Get the perfect sanding, shaping or slicing power tools for your needs at your nearest BUCO. Take a spin to your nearest branch today and find out about the best options for your build from our friendly experts.


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