It can be a bit dangerous to cut metal with an angle grinder. There are a ton of things that can go wrong and that will go wrong if you don’t follow the proper steps when using an angle grinder.
If you aren’t sure what an angle grinder is and what it is used for you can read on “What is an angle grinder” here.
How to use an angle grinder and cut metal safely.
Step by step guide
- First of all, you should wear the correct PPE (personal protective equipment).
- Safety goggles and/or face shield
- Safety shoes. Steel toe shoes made from a hard, rugged material. Avoid soft materials, because they can catch on fire.
- Heat-resistant overalls or jeans. Avoid short pants, sweat pants, or any pants made from thin material.
- Try to avoid loose-fitting gloves, this can compromise your grip on the angle grinder
- Check your grinder before cutting.
- Make sure the guard is in place
- Disk is safely secured
- Wires aren’t damaged
- Make sure you have the piece you want to cut secured to a sturdy work table.
- Also check that the correct wheels are used with the grinder. The rpms match and don’t ever use the wrong size wheels for the grinder. E.g 4.5 inch wheels on a 7 inch grinder.
- Stand with your two feet apart, make sure you are also standing on sturdy ground, or are securely fixed to one position.
- Hold out the grinder in front of yourself with both hands fixed on it. One hand at the bottom and another on the top/front handle.
- When you start to cut.
- Move the grinder slowly towards the material
- Do not apply too much pressure
- Do not press the wheel against the material before switching on the grinder.
- Read in how to cut any profile.
- The sparks should be flying toward you. It might seem like they shouldn’t, but you have more control over the grinder.
- Try to let the sparks pass between your legs or pass one of your sides. Also, look out that the sparks don’t ricochet against something and hit you in return.
- Make sure there is no one around you or surround yourself with welding screens to create a safe area
- Clean out your work area, and remove any tripping hazards or flammable liquid/ material around you when grinding.
- After using it and you want to remove the disk. I made a full and comprehensive guide on removing a disk in any situation here.
What you should look out for when cutting metal with an angle grinder.
A couple of things can go wrong when cutting metals. Making mistakes is very dangerous and should be avoided at all costs.
The main things that can go wrong when cutting metals are:
- Slowing down the rotation of the grinder, struggling to cut
- Getting stuck between the metal while cutting
- Light to harsh kickback
Why are you struggling to cut with an angle grinder?
This is mainly caused in one of two ways that are easily avoided and should be taken into consideration when using an angle grinder.
- Firstly the piece of metal you are cutting is too thick or hard for the grinder you are using to handle
- Secondly, you might be applying too much force to the grinder.
Both of these should be avoided because you can burn out the armature on the grinder and you will be wasting your time. Rather use the right size grinder for the job.
Sizing chart for which size grinder to use for the thickness of the steel
Angle grinder size | Low carbon steel | High carbon or Stainless steel |
4.5 inch – 115 mm | 1.6 – 3mm | 1.6 – 2mm |
5 inch – 125 mm | 1.6 – 4mm | 1.6 – 3mm |
6 inch – 150 mm | 1.6 – 6mm | 1.6 – 4mm |
7 inch – 180 mm | 2 – 8mm | 2 – 6mm |
9 inch – 230mm | 3 – 12mm | 3 – 10mm |
Please note this is just a guideline and you should use your discretion when working with power tools.
If you are looking to cut out odd shapes or very thick metal you should consider an oxy-acetylene cutting torch or a plasma cutter.
Just remember, you can not cut stainless steel with an oxy-based cutting torch because it has a very high heat capacity and melting point.
How to avoid getting the cutting wheel of an angle grinder stuck.
Avoid this by keeping the grinder firm and sturdy while you are cutting. Keep your eyes on what you are doing constantly and follow my steps on how to cut and hold an angle grinder for cutting.
Light pitching and swaying are the main reasons why the cutting wheel will get stuck between the metal that you are cutting. Heavy pitching and swaying will result in harsh kickback.
How to avoid kickback on a grinder
Best way to avoid getting any sort of kickback with an angle grinder is to start by using the angle grinder in the correct way.
- Proper posture and grip.
- Securing the piece that you want to cut correctly.
- Cutting slowly.
- Check the top of the article for the proper usage guide that I personally follow.
Disk after kickback
What can cause your grinder to kickback?
Sudden stopping of the rotating wheel causes kickback. For example, While cutting a piece of angle iron, the piece starts to sag with the cutting of it. This in turn will “bite” the cutting wheel and result in a sudden and violent kickback that will hurt and damage the grinder.
I have had this happen to me and it is painful, to say the least. I remember being shocked, angry, and scared at the same time. Also struggling to get the broken wheel off the grinder is stressful. Because the sudden stop tightens the wheel a lot.
The wheel can even shatter when this happens and can result in very painful injuries. I have personally never had this happen, but I always spend the extra buck to get high-quality wheels that will rather chip than shatter. Also just avoid cheap wheels because they don’t last as long and can even shatter while just spinning.
You should make sure the wheels you have, match with the grinder’s rpm. Don’t ever put a 2000 rpm wheel in a grinder that runs at 3000rpm, you will have a bad time.
What blade do I need to cut metal with an angle grinder?
Cutting wheels/discs are the only wheels you should use to cut metal with. You will see that the cutting wheels will have a thin flat appearance to them. Just make sure you are using high-quality wheels and you have the correct wheel size that matches the grinder’s size. You will also need to know how so follow my steps at the top of this article.
Dangerous of an cutting wheel in an angle grinder
An angle grinder is a high-power tool with an extremely fast spinning wheel that can cut through metal, concrete, and most hard objects. So the amount of damage it can do to your body is a lot and can result in severe injuries. That is why I recommend following this article for the best knowledge and advice from a trained professional. Also, check out what are angle grinders used for.
