How To Turn Angle Grinder into Circular Saw

  • By: Monica Shulz

Upcycling your tools to give them a new lease on life is always a great idea! This way, you get to save money on new tools and reduce waste from your workshop.

To help you with this, we’ve created this guide to show you how to turn an old angle grinder into a circular saw. We’ll show you how to salvage the angle grinder’s key parts and put them to new use.

So, let’s get to the workshop and start building.

What You’ll need?

Before you start making the circular saw, you’ll need to gather a few items. They include:

  • An Old Brushed Motor Angle Grinder
  • And Old Corded Drill
  • 1cm Square Metal Pipe
  • 3mm Thick Metal Plate
  • 5mm Thick Metal Plate
  • 4” diameter Circular Saw

Disassemble The Angle Grinder

Place the angle grinder on the workbench, remove the grinder lock nuts and remove the cutting disc. Take a screwdriver and undo the screws on the bottom of the angle grinder.

Remove the screws and undo any other screws holding the bottom of the angle grinder to the body. Next, remove the bottom of the angle grinder.

Go to the head of the angle grinder and remove any screws holding it to the angle grinder’s body. Now, pull out the head of the angle grinder from the body.

It should be connected to the motor’s rotor via a shaft.

Remove The Spindle from The Head

Turn the head of the grinder, so it’s facing you. Using a screwdriver, remove the screws holding the face of the grinder in place.

Once the screws are loose, remove the face of the grinder. Remove everything, including the geared arrangement and the spindle.

Remove The Shaft from The Head

Use a Dremel circular saw to cut out a section from the flange between the angle grinder’s head and the shaft. Once you’ve cut out the section, locate the screws that attach the shaft to the head.

Remove these screws with the screwdriver and separate the shaft from the head of the grinder.

Cut Off The Rotor from The Shaft

Place the shaft in a bench vise and clamp it tight. Using an angle grinder, cut the rotor off from the end of the shaft.

After this, remove the flange from the shaft of the angle grinder.

Re-assemble The Head of The Grinder

Take the head of the grinder and clean it with a wire brush to remove any dirt or rust inside it. Next, place the shaft back in its place and screw it tightly to keep it from falling out.

After you’ve placed the shaft back in, add some lubricating grease to the inside of the grinder’s head. Add some grease to the spindle and geared arrangement you removed earlier.

Place the face of the grinder with the spindles and the gears back in the head. Secure it in place with the correct screws.

Next, slide on the inner and outer lock nut flanges on the shaft.

Cut The Collar for The Circular Saw

Place the corded drill on the workbench. Use a caliper to measure the drill’s neck, the part just below the drill’s chuck.

Take a cylindrical metal pipe with a diameter of 3cm and clamp it on your workbench. Mark out a 2cm long section from the pipe and cut it out.

This will be the collar for the circular saw.

Increase the Size of the Collar

Place the collar in a vice and clamp it tightly. Use an angle grinder to divide the collar at a point on its circumference.

Now, remove the collar from the vise and heat the section directly opposite the cut with a blowtorch. While the section is still hot, gently widen the collar by pulling its ends until it can fit around the neck of the drill.

Fit The Collar on the Drill

Take a long M10 bolt and screw on two M10 nuts. Place the collar back on the workbench and place the bolt with the nuts right between the collar’s gap.

Make sure each nut on the bolt is placed on the end of each gap section on the collar. Now, place the collar back on the neck of the drill.

Place the collar, so the gap on it is facing upwards. Now, place the bolt on it, with each nut resting on the ends of the collar.

Weld the nuts to the ends of the collar. Place another nut on the end of the bolt and tighten it to achieve a tighter fit.

Connect The Grinder Head To The Drill’s Chuck

Use the key to loosen the drill’s chuck. Place the angle grinder’s shaft in between the chuck jaws and tighten the chuck on the shaft.

Make sure the shaft is seated properly before you tighten the chuck.

Cut-Out Supports For The Grinder Head

Measure the distance from the base of the grinder’s head to the collar on the drill’s neck. After this, Place the 10cm square pipe on the workbench.

Add 1cm to the dimension you measured and mark out four sections with this dimension on the profile pipe. Cut them out with an angle grinder.

Drill Screw Holes in The Supports

Take one of the supports you just cut and clamp it in your bench vise with one end facing upwards. Mark a 1cm section at the top and cut along the seams in that section to separate it into four different walls.

You can use the angle grinder or a Dremel cutter for more accuracy. Next, cut off one of the walls, fold one outwards and fold the remaining two inwards.

Drill a hole in the one you folded outwards. The hole should be the same size as the hole on the head of the grinder.

Repeat the same thing for the remaining supports.

Connect The Supports To The Grinder’s Head

Place the support section with the hole under one of the holes on the base of the grinder’s head. Put a bolt through both holes and join them together with a nut.

Make sure you tighten the nuts properly with a spanner, so the supports stay in place. Repeat this process for the rest of the screw holes on the grinder head and the remaining supports.

Weld The supports To The Drill’s Collar

Place the drill on its side and make sure the spindle is facing straight up. Make sure the spindle is at a proper 90° vertical.

Once you’ve done this, take one of the supports connected to the grinder’s head and place it on the collar. Weld both of them together.

Repeat the same process for the remaining supports. However, be careful not to weld any supports to the last nut on the collar’s bolt, as it is only meant for tightening.

Cut Out A Base Plate For The Saw

Take the 3mm thick metal plate and mark a 5cm wide and 25cm long section. Cut out the section from the main plate using an angle grinder.

Next, mark a new hole right in the middle of the blank you just cut. It should be 15cm long and 3cm wide.

Cut out the section you just marked with an angle grinder. Smoothen the edges with the grinder to remove any burrs left on the workpiece.

Add The Saw Blade to The Grinder Head

Remove the top locking flange from the grinder head’s spindle. Place the saw blade on the spindle and balance it on the lower flange.

Place the top locking flange back in place and lock it with the provided tool.

Add The Base Plate to The Saw

Place the drill upside down so that the saw is facing the right. Now, place the base plate over the saw.

If the hole isn’t wide enough for the saw, you can increase it using the angle grinder. Once the base plate can fit comfortably over the blade, ensure it is perfectly level and weld it to the support.

After welding it to the support, you can also weld it to the collar for a sturdier joint. Clean the weld with a wire brush.

Fabricate a Guard For The Saw

Take a 5mm thick, 2cm wide metal plate and cut out a section about 35cm long from it. Place the section in the bench vise and clamp it.

Apply heat to the middle of the section and bend it using a cylindrical metal rod or a mallet. The final section should have a curved shape that can go over the circular saw’s blade.

Add the Guard To The Saw

Now, place the guard you just fabricated over the blade. One end of the guard should be touching the top section of the base plate, and the other should be touching the collar.

Weld the guard to the base plate at the top. Afterward, weld the guard to the collar and the supports at the bottom.

Install The Handle On The Grinder’s Head

Take the handle you removed from the grinder and screw it back into its spot on the grinder’s head. This will make it easier to control the motions of the saw when you’re cutting with it.

Final Product

The upcycling process is complete! Now you have a nifty little circular saw that you can use for cutting wood around your workshop.

Great Job!

If you enjoyed this project, you can find more like it on the Mr. DK DIY channel on YouTube. You can also subscribe to his Facebook page for more updates and DIY recommendations.

Photo by Mr. DK DIY / CC BY 3.0