HOW TO GUIDES

How to Remove an Angle Grinder Disc [Easy Way]

There are several ways to remove an angle grinder disc, depending on the tools you have. The simplest method is to use the included factory keys. However, if you bought your used angle grinder and the keys are missing, there are other ways to remove an angle grinder disc without a tool.

So how do I change an Angle Grinder Disc ?

According to the instruction manual, replacing the disc on the grinder should be done as follows:

  1. Unplug the power cord from the outlet.
  1. Press the spindle rotation lock button.
  1. While holding the grinder stop button, unscrew the flange nut using an open-end wrench.
  1. Turn the key for angle grinder in the direction of rotation of the disc. If it is difficult to press the button with one hand and use the key as the second, ask someone close to help you.
  1. Remove the old disc from the spindle shaft. Install a new disk. Fix it with a nut by hand or with the same universal wrench.
  1. At this moment, you need to hold the stopper with your other hand. Do not tighten the nut strongly.
  1. Connect the grinder to the spindle shaft for 30 seconds at maximum speed. If the disc rotates freely, without beating, without touching the protective casing, you can start working.

Now I’m going to explain you step by step instruction how to do this procedure!

TIP!
Attention! Before starting to remove the disc, make sure that the angle grinder is disconnected from the power supply!

How to Remove an Angle Grinder Disc Step by Step

How to Remove an Angle Grinder Disc

Step 1. Disconnect the power

Warning: If you do not turn off the power, you may injure yourself. Make sure that the power is completely off before proceeding to the next step.

To avoid injury from accidental use, it is important to disconnect the power source from your angle grinder. For a corded angle grinder, make sure it is unplugged from the wall outlet.

If you have a cordless angle grinder, remove the battery from the tool. Removing the battery will also make the tool lighter and easier to handle when changing the angle grinding disc.

Remove the Angle Grinder disc with factory keys

Step 2. Remove the Angle Grinder Disc

Removing the Angle Grinder disc with factory keys

press the spindle lock button

Your new grinder comes with two separate keys that look like flat wrenches. One wrench will look like a normal wrench, while the other will look like a two prong fork. Insert the pins into the two holes that appear in the drive bolt between the disc and the angle grinder motor.

Use the adjustable wrench to attach the bolt to the bottom of the disc. Turn the hook wrench in the opposite direction of the rotor direction arrow, located on the bottom, while using the adjustable wrench to prevent the rotor from turning.

use the key to remove the disc

There may also be a button on your side grinder that will hold the disc in place. Turn the nut until the disc comes off the tool.

remove the disc from the angle grinder

Removing the Angle Grinder disc with improvised keys

Securely attach the clamp handles to the bolt holding the disc to the lock nut bolt. Use the jaws to prevent the disc from rotating, and insert the screwdriver into one of the holes between the disc and the angle grinder motor, intended for the claws of the wrench.

Pull the screwdriver in the opposite direction to the arrow on the disc. If it does not come off immediately, use a hammer to force the screwdriver to turn.

Removing the Angle Grinder disc without keys

Using the palm of your hand, slide the disc in the direction opposite to the arrow on the disc. This should loosen the nut enough to remove it with your fingers.

If that doesn’t work, you can use pliers to break the old disc into pieces, giving you better access to the drive bolt and retaining nut.

TIP!
Remember each time you change the disc to coat the screw thread with grease.
You can also use penetrating oil during the unscrewing operation if a dry crust has formed.

Step 3. Install a new Angle Grinder disc

Place your new grinding disc on the drive bolt in the same way as the old one on the drive bolt. 

It is important to use a disc made for your particular make and model of angle grinder. If you are not sure, take the old disc to your hardware store and ask an employee.

Finally, hand-tighten the new disc in the opposite direction from which you removed the old disc. 

Your angle grinder should now work properly. If you need to replace the grinder motor after installing a new disc, you can easily do it now.

How do you remove an angle grinder disc without a tool?

Method 1. Use a gas wrench to remove the angle grinder disc

Grasp the nut with an adjustable pipe wrench and loosen it carefully, without applying great force. Disadvantage: you can crush the lock nut, break the rotation lock.

Method 2. Make a homemade key for the angle grinder.

To do this, you need a long nail (at least 100 mm). It is necessary to cut off the hat, the point and give the nail a U-shaped.

It should be bent in such a way that the “tool” stands fall into the flange holes. If the nut is tightened tightly, insert any metal bar between the posts of the nail and, grasping it with both hands, rotate the structure in the direction of the circle’s movement.

At this time, you need to press and hold the spindle lock button. The method is safe, but it takes time and additional tools – a hacksaw, a vice, a hammer.

Method 3. Tapping the disc with a chisel.

Before changing the disc, you can treat the spindle shaft with WD-40 fluid and wait at least 15 minutes.

Then place the tip of a thin chisel at an angle to the hole of the flange nut and gently tap the entire surface of the hole with a metal hammer.

Sooner or later, thanks to mild tapping, the nut will be removed, and it will be possible to unscrew it manually.

The disadvantage of this method is that you can damage the holes and spoil the flange.

Method 4. Heat the nut of the angle grinder

If it is difficult to unscrew the angle grinder nut by hand, you can heat it up a little with a gas burner or autogenous welding machine.

You need to unscrew the flange with gloves so as not to burn yourself. This is the most risky of the proposed methods. You can overheat the bearings and oil in the gearbox of an angle grinder.

How do you unscrew a grinder?

First of all, to prevent the blade from being injured when changing the disc, before proceeding make sure to disconnect the grinder from the wall socket, and then remove the battery to make the tool more manageable. 

Removing the disk basically consists in using the two keys that you will previously find included in the grinder package, and inserting the tips in the holes on the bolt of the unit and then unscrewing it slowly.

How to remove a disc from a grinder if it is broken and tightly clamped with a clamping nut?

Usually the angle grinder disc can be changed without any problems and within just one minute. But what if this no longer works, for example due to stuck or rusted nuts?

In most cases, there are several ways you can use to solve the problem of stuck angle grinder disc or their mounting nuts. Here are some of them:

  • clamp the disc in the vice and loosen the nut
  • cut the nut with a second angle grinder
  • use rust remover
  • use a nail
  • heat up the nut of the angle grinder

Replacing the disc with opposite rotation

This method has several advantages – it can be carried out without a key and with a broken spindle lock. 

Newbies in working with angle grinders mistakenly believe that if the stopper is broken, it is almost impossible to unscrew the nut. However, this is not the case. You don’t even need keys.

The bottom line is that the abrasive wheel needs to be rotated in different directions. Wearing thick gloves, you need to hit the cutting edge of the circle several times. 

This is what you will provide variable movement in different directions. As a rule, a couple of sharp blows are enough so that the nut can be easily unscrewed.

With a nail

For these purposes, a nail of 100 mm is best suited. It should be bent into a U-shape so that the ends fit freely into the holes of the clamping flange. 

The tip and cap are removed. By inserting a nail into the holes, the retainer is unscrewed. If there is not enough hand effort, add a nail or a screwdriver in the form of a lever.

Lubricate the threads with penetrating grease. 

Pour WD-40 liquid on a stuck nut. It penetrates into narrow gaps and threaded connections. After a five-minute break, try to move the nut with a wrench.

We heat the nut with a burner

We heat the seated nut with a portable gas burner. The nut will expand from heating and can be easily unscrewed from the angle grinder.

Cut out the remaining disc with a hacksaw

We break the disk with pliers while it is possible. Remove the protective cover, insert a metal hacksaw into the slot and cut out the remains of the abrasive wheel. 

A delicate and reliable method. Does not require disassembly of the angle grinder and harsh impacts on the tool. 

You must be patient, as the method will take up to an hour. The abrasive quickly erases hacksaw blades, several of them are required. 

Advantage – preservation of the guarantee for angle grinders, there is no risk of breakage.

Tapping the nut

This method is similar to the previous one, only you can use a suitable metal rod or chisel. After fixing the spindle head, tap along the edges of the clamp holes in the direction of movement of the circle. 

Slightly moving the latch off the ground, you can unscrew it by hand. However, the method is not the most harmless for the tool – the mounting holes for a standard key are damaged.

When should I replace my angle grinding disc?

The most common “symptoms” of a angle grinding disc that is worn and needs to be replaced are:

  • Unusual vibrations during cutting.
  • Visible signs of deformation or damage.
  • Slow cutting speed
  • Strange noises while cutting

If you run your fingers along the edge of the disc and it is very smooth, it is a symptom that you need to change it. To the touch it must be rough and therefore abrasive and maintain its cutting property.

Conclusion

The operation of removing the disc from an angle grinder is not difficult at all and there are several ways how to do it, but nevertheless requires some precautions both as regards the disassembly and assembly of the new disc.

The main thing is that when changing a disc on a grinder, do not violate safety precautions and remove the disc with the angle grinder turned off.

Always work with discs in good condition, change your disc if it is too small, damaged or bent. Install it in the right direction, check its tightening, take the opportunity to check the tightening of the housing.

Depending on your work, ventilate your site, equip yourself with protective glasses, earplugs.

How to change a keyless angle grinder disc?

On some models of grinders, you can change the disc without a key. This tool-less change is very fast. You just need to hold down the button opposite to the clamping screw. This will have the effect of blocking the disc. It is then possible to put a new one in place and to come and tighten the clamping nut manually. While keeping the button pressed, it’s up to you to screw your disc to the maximum.

In what direction to mount a diamond disc on a angle grinder?

How to be sure to place your grinder disc in the right direction? 
To help you, see the arrows on the disc. 
Two arrows are there and show you the direction of rotation intended for the disc. 
You just have to place it so that it turns in the right direction once the grinder is running. 
The correspondence between the direction indicated by the arrow and the actual direction of rotation gives you the guarantee that the disc is correctly placed.

Adrian Tapu

Adrian is a seasoned woodworking with over 15 years of experience. He helps both beginners and professionals expand their skills in areas like furniture making, cabinetry, wood joints, tools and techniques. Through his popular blog, Adrian shares woodworking tips, tutorials and plans related to topics such as wood identification, hand tools, power tools and finishing.

Adrian Tapu has 159 posts and counting. See all posts by Adrian Tapu