
This is something that happens to me all the time: I tend to lose stuff right when I need it. So I often need to improvise to get the job done. One thing that I often lose is the wrench that you use to unlock the blade of the angle grinder. Or maybe you are more precise than me, but you happened to get a second-hand grinder and the spanners are missing, or you got the tool from a friend and he forgot to lend you the key.
Whatever the case may be, don’t worry: in this article, I’m going to walk you through the answer to the following question: How do I change an angle grinder disc without the appropriate tool?
The quick answer is the following: You need something that mimics the tool’s action: you can use a hammer and a chisel, a couple of bolts and pliers, or even your bare hand. In the latter case, be careful: wear a pair of gloves to prevent cutting your hand.
Now, I’m gonna explain to you in detail how to get the job done in all these possible ways. If you are a beginner and you stumbled upon this article, I will also tell you how to remove the blade of the grinder with the appropriate wrench.
1. Unplug the power source

The first and most important thing you need to do is to disconnect the power source of your angle grinder. This is to prevent accidental ignitions of the angle grinder that may cause you an injury. If you have a corded angle grinder, unplug it from the wall outlet; if you have a cordless angle grinder, you should remove the batteries from the tool.
Now, you may think that this is just a waste of time, that you’re not that dumb to cut yourself while doing such a simple task. Well, I think that is better to be safe than sorry, and wasting those 30 seconds to unplug the grinder is better than getting a brutal cut on your hand. So please, make sure that the power is completely off before continuing to the next step.
Now, I’m gonna explain to you some possible ways to change your grinder’s blade without the appropriate wrench.
2. How to remove an angle grinder disc without the tool
Now, I’m gonna show you three possible solutions to get the job done. After that, I’m going to teach you how to do it with the factory spanners. So, if you are a beginner, that’s the section for you.
Solution 1
The first way to do it is to mimic the wrench action with something else: for example, you can use a couple of bolts and a pair of pliers. First, you need to find two bolts that fit into the grinder locking nut that holds the disc, then you grip them with the pliers and rotate it counterclockwise. While doing this, you need to lock the grinder’s wheel using the lock button which is situated on the top of the angle grinder, behind the disc. Keep the button pushed to block the disc.
You can create your adjustable wrench from this strategy: take the bolts and weld them on some old pliers. This way, you are going to have a pair of spanners that go with different sized grinders.
Another tool you can use for the job is a pair of vise grips: you lock them around the grinder locking nut and rotate them counterclockwise to unlock the disc. Remember to keep the lock button pushed while rotating.
Solution 2

However, the lock button might be stuck. I saw some very old grinders that didn’t even have one. In this case, you can remove the disc by using a hammer and a chisel. To do this, you need to put the tip of the chisel inside one of the holes of the locking nut. Remember to incline the chisel to a certain angle: you need to mimic the rotation of the disc.
After that, hit the chisel with the hammer so that the nut would rotate counterclockwise: you might need a couple of hits to unlock the disc.
Be careful with this method: using a chisel, there’s a high chance of damaging the holes of the grinder locking nut. You should use this method only if you have no other alternative.
Solution 3
This is the last resort: you are going to use your bare hands for this one. Well, not exactly bare: you should do this only after wearing a pair of good gloves. Otherwise, you are gonna cut your hand for sure.
The instructions are the following: while holding the lock button on the top of the grinder, you need to strike the disc with the palm of your hand in the direction opposite to the grinder’s rotation. This should get the nut loose enough so that you can remove the disc with your hands.
Here’s a very well made video showing you how to remove the disc with your hands:
While using this technique, there’s a risk of breaking the disc (especially if it’s very worn out). In that case, you need to remove the piece of the disc still attached to the drive bolt with one of the methods I showed you above.
How to remove an angle grinder disc the appropriate way
Now that I’ve shown you how to remove an angle grinder disc without the tool, I’m going to tell you how to do it with the appropriate tool. You are going to use a wrench that looks like a two-pronged fork (sorry, it’s almost dinner time when I’m writing this…). Those 2 prongs come with a knob each: that’s the part you have to insert into the grinder locking nut’s holes. Then, you simply rotate the wrench in the direction opposite to the grinder’s rotation (while holding the lock button down to keep the disc still). Turn the nut until the disc is loose enough to be removed by hand. Easy, right?
However, there’s a problem you could run into. Maybe you have more than one angle grinder: if you are like me, you got at least a couple of grinders: a small one to do the small cuts and the quick grinding, and a bigger one, to do the heavy-duty work. And of course, the grinder locking nut size depends on the size of the grinder. So, you might end up with a bunch of spanners, and you will never pick up the right one first try, trust me.
To avoid this, there’s a quick trick: put one of the wrench’s knobs inside a hole of the grinder nut, and then use the side of the nut as a lever to unlock the disc. That’s a simple application of the principle of the lever that will save you some time (and make you look smart if your wife is around).
Alternatively, get yourself an adjustable pin wrench like this one:That way you can easily adjust the pin’s clearance to fit your angle grinder.
3. Put on a new disc

After you have loosened the locking nut, you can remove the disc with ease. Most of the job is done. Get a new disc, and put it in the drive bolt. Then lock it in position with the locking nut. Make sure that you are using an appropriate disc for your angle grinder model. If you are not sure, take the old disc to your local store and ask an employee.
To tighten it, rotate the nut in the opposite direction than before using one of the techniques you learned above. For example, hit the nut with the hammer and the chisel in the direction of rotation after tightening it by hand. To be honest, hand-tightening the nut and then giving the disc a spin with your hand is more than sufficient. The blade is going to tighten itself when you turn the angle grinder on for the first time.
That’s it, your angle grinder should work just fine now.
Conclusions
In this article, you learned that changing your angle grinder blade without the appropriate tool is not a big deal. There are several ways to do it, and if you ask a handyman, he will probably give you some other options. The last thing I want to tell you is to always put your safety first. That’s the reason why I put so much emphasis on unplugging the grinder and in using a good pair of gloves to loosen the grinding wheel with your bare hand.
If you don’t feel safe with the tips I wrote about, you could buy a wrench key. Just make sure that it fits your angle grinder. The best way to avoid buying the wrong wrench is to get an adjustable one: this way, you could use it for all your grinders, from small to big ones. There are a lot of cheap choices on Amazon. If you feel like it, you could even build one yourself, as I showed you in one of the paragraphs above.
That’s it, see you in the next article!