How to Control an Angle Grinder Speed + A DIY Controller

Do you get frightened by the deafening sound of an angle grinder? It’s a natural and logical response because, undoubtedly, they are one of the most fatal power tools. Do you know you can control the speed of an angle grinder even if it doesn’t have this feature?

I know it would be frivolous to write how to control an angle grinder’s speed if it already has a speed-controlling mechanism because it’s not rocket science to figure out how to fidget a control ring or press a magical button with a few numbers written on it.

In this article, you’ll learn how to reduce the speed of an angle grinder to gain more control, efficiency, and safety. This process allows you to use your angle grinder for several applications, such as polishing, sanding, or fine grinding. So, let’s do this.

How to Control the Speed of Angle Grinder

There are three primary methods to control the speed of an angle grinder:

Variable Speed Grinders: These grinders have a built-in speed control dial that allows you to adjust the speed according to the task. They are usually costly, and if you have them, you already know how to change their speed.

After-market Speed Control Devices: If you have an angle grinder without a built-in speed controller, you can still rein it down with after-market devices. You need to plug your grinders into the socket of these devices as you usually do with mains. And you will have the ability to control your grinder’s speeds.

DIY Speed Controller: You can also make your own speed controller. The best part about it is you’ll be free to make it according to your needs.

Now let’s understand Step-by-Step how to use all the above methods to control the speed of our angle grinder.

1. Angle Grinders with Variable Speed Control

It’s self-explanatory and straightforward. If you have a grinder that offers a built-in method to adjust the speed of the grinder, you can easily do it. Just locate the adjust button or ring and follow the manufacturer’s instructions.

2. After-market Speed Control Devices for Angle Grinders

You can purchase an after-market device if your grinder has no built-in speed controller. An SCR (Silicon Controlled Rectifier) is the backbone of these speed controllers. They come with a knob that allows you to adjust the voltage output.

You must insert the plug into the device socket to control your angle grinder’s speed. Moreover, that controller must be connected to the mains.

Now, the power will go through the controller to your angle grinder, which you can adjust.

Also read: How to cut metal with an angle grinder

3. DIY Speed Controller for Angle Grinders

I love DIY stuff and made a speed controller myself. It’s useful not only for controlling the speed of an angle grinder but also for any power tool up to 2500W, which is fantastic.

So how can you make it? Here is the process and required items.

• An SCR voltage regulator
• An AC socket
• An on/off switch
• A casing or housing for our controller body

First, let’s understand the connection of an SCR voltage controller. You must find the input and output written on the controller. As you can see in the above image.

Now, you need to connect the two input wires to the main.

Meanwhile, the output wires will go into the socket through a switch.

That’s it. According to your requirements, you can fit this system into a casing or the main board. In the image below, you can see that I have made an extension board with an SCR voltage controller. You can make your own version.

FAQs

Conclusion

That’s it; we have discussed multiple ways to control our angle grinder’s speed. Please tell me which one you find the most helpful. By limiting the speed of an angle grinder, you can make the most of it, use it for several other purposes, like polishing and sanding. If you have any suggestions or feedback, please comment below. Thanks for reading; until next time, keep crafting!