Tutorials

Introduction

A cut power cord doesn’t necessarily mean a power tool belongs in the trash. In this case, the cord on my Skil 7-1/4″ circular saw was accidentally cut, so I decided to replace it rather than replace the saw.

This repair required disassembling the handle, replacing the damaged cord, making a new strain relief with my 3D printer, and reconnecting the wiring.

If you don’t feel comfortable doing electrical work, or disassembling a power tool, find a repair center. I should note that if you have any kind of warranty on your item, this repair will likely void that warranty.

The Problem

The problem that required the replacement of the cord was that the cord was inadvertently cut.

The Solution

The solution to this problem was to replace the cord entirely. This required the disassembly of the handle, creating a new strain relief, and connecting the wires inside.

Parts

For this fix, I needed just a few parts:

• New power cord
• New strain relief
• Wago lever nuts or wire nuts

The Fix

Disassembly

To access the inside of the handle, you need to remove these six T-20 Torx screws. You need a long shaft on the Torx bit to access the recessed screws.

In the image above, I took off the black cap that covered the motor, but that is not necessary as all of the connections are in the handle. The two wires that we need to splice are the white and black wires leading up to the switch. While it is possible to cut away the heat shrink and desolder the connection to solder on new wires, I decided to splice the wires instead. That way, if the cord was ever damaged in the future, I just have to connect the new cord to the Wago connectors.

Cutting The Wires.

Use a simple pair of diagonal cutters or flush cutters to snip the white and black wire. I cut mine close to the power cord strain relief so I had plenty of wire to work with.

New Strain Relief

The strain relief is the black conical piece of plastic at the connection point between the cord and the saw. In the case of most strain relief devices, they are molded into the jacket of the power cord, and therefore cannot be reused. One option to replace it is to buy a new cord from Skil, if that is possible (I didn’t check on that). The other option is to make a new strain relief.

I decided to make a new one with my 3D printer. I measured the old strain relief and modeled it in Fusion. My design included a way to install strain relief around an existing cord. My strain relief splits down the middle to get it around the cord. I added two relief grooves that could accommodate zip ties to hold the two halves together. I could have designed it with screws, but that would make it too bulky and it might not fit in the saw.

Part of the function of the strain relief is to make sure the power cord doesn’t pull out and put strain on the wires inside. In order to make sure this new design accomplished that, the diameter of the hole had to be slightly smaller than the diameter of the cord jacket. That would allow it to compress the jacket and lock it in place with friction. This took some trial and error to get right because the hole can’t be too small otherwise the strain relief would not completely close, which it needs to do to fit in the saw.

Wire Connections

I purchased a simple 6 foot extension cord that was flexible. Home improvement stores often carry dedicated power tool replacement cords, but they are more than double the cost. To use a regular extension cord, you just have to cut off the end (NOT the end with the prongs), and strip back the insulation to access the wires.

An extension cord that is durable enough for this application is likely going to have 3 wires (hot, neutral, and ground) as mine did. The Skil Saw does not require a ground wire so after I stripped off the insulation, I simply snipped the ground wire off. I located the best place for the Wago lever nuts to go and then cut the wires to size so they reached but didn’t have too much excess. The handle is a little limited on space.

To make the connection, you need the two-wire Wago connectors or you can use two twist-on wire nuts. I prefer Wagos whenever I can use them because they provide a good connection and are easier to disconnect if the cord needs to be replaced again. Remember when making the connections to connect black to black and white to white!

I positioned the Wagos in two different voids in the handle. Both of the connections couldn’t be in the same void because there wasn’t enough space. It doesn’t matter which one you use, but they will likely need to be separated.

Reassembly

Now that you have made your connections, it is time to reassemble the handle. Make sure the strain relief is situated in the notch. Notice in Figure 6 how I oriented the split on the strain relief to be perpendicular to the split on the handle. This makes reassembly a little easier and helps hold the strain relief together until you zip tie it.

You may have to make some small adjustments to the wires and connectors to get the handle halves to sit back together properly. Once the handle is together, reinstall the screws. These are metal screws going into a plastic housing, so make sure you don’t overtighten them or you could strip the plastic threads.

After the screws were installed and the handle was secured, I added the zip ties to the strain relief to make sure it stayed in place. If you go this route, just make sure the head of the zip tie is on the bottom so you don’t have to worry about scratching yourself every time you use the saw. Now you have a working saw again!

Thanks

Thank you for reading my post. If you find that you gained some knowledge and would like to read more, please consider giving us a like and subscribing. It’s free and it helps us get sponsors for future content. Also if you feel we are worthy of a small donation, you can leave a tip at the button below. Every little bit helps as the projects can be quite costly.