Wire Harness Wrapping Mashine

Wire management used to be a mess, but not anymore. This tool is simple, super quick to use, and it’s powered by a cordless drill battery.

How I did it - you can check by looking DIY video or you can follow up instructions below.

For this project you will need:

Materials:

1. 5mm PVC sheet
2. Plywood 18mm (or similar)
3. 20T idler pulleys (with and without teeth): Link here
4. Timing Belt Pulley for motor 60T: Link here
5. Timing Belt (length according your setup): Link here
6. Motor 12V 319rpm: Link here
7. Speed controller: Link here
8. Pedal switch: Link here
9. CA glue
10. 3D printed 12V battery holder: Link here

Tools:

1. Drill, drill press and bits
2. Palm router with 6mm bit
3. any other various bits and bobs which helps to get job done in the workshop

I started with a 6mm PVC sheet and drilled a 3mm hole in the center. That same drill bit was used to guide the palm router with a circle-cutting jig. I’ve used this method many times before, and it always gives me a clean, perfectly round cut. It's quick, reliable, and saves a ton of time compared to other shaping methods.

I flipped the jig and clamped it to the workbench. That same 3mm drill bit now centers the inner cut. This time, we’re cutting out the inside of the circle. Once that’s done, I bring the piece over to the table saw to cut a straight slot. That slot transforms the disc into a ‘C’ shape. It might seem odd now, but trust me, you’ll see why this step is important very soon.

Now I moved on to building the base from 18mm plywood. I drilled the center hole using a drill press to ensure it was perfectly aligned and perpendicular to the surface. For the outer shape, I used the same palm router setup from earlier. A few small marks allowed me to reposition the jig to carve the inner circle accurately. I used a spiral router bit again here - it gives that smooth, clean edge that looks almost finished straight off the tool. To complete the match with the PVC disc, I made the same kind of ‘C’ shaped slot on the table saw. This part of the base is what supports the main structure, so it needs to be exact. Each cut and edge matters here to make sure everything lines up and runs smoothly later. Precision at this stage is key to avoiding problems down the road, especially when everything starts spinning.

Now things started getting interesting - time to mount the moving parts. I carefully marked and drilled holes to install the pulleys. For shafts, I used M5 hex bolts. Each one got a washer on one side and two nuts on the other. Normally, one nut is enough, but I needed some extra spacing from the plywood, so I added a second. It’s pretty satisfying to see it all line up - solid and precise.

I used 20T idler pulleys: three silver with teeth and four black without. Assembly order matters here: install all four toothless pulleys first, then add the PVC disc, and finally the silver pulleys. These will guide the GT2 timing belt.

Once the belt was temporarily placed, I added the final 60T pulley.

Placement is everything here - the pulley needs just the right amount of belt tension. So I marked everything carefully. You’ll notice the hole for this pulley is much larger than the shaft itself. That’s because I’ll be mounting a DC geared motor here, and the pulley connects directly to it. The motor needs to sit deep in the plywood, so I drilled a large center hole and three smaller ones for mounting screws. I also countersunk them for a flush, clean look.

Now onto assembly - each small pulley bolt gets a nylon nut. It might look like I’m tightening them hard, but they’re actually just snug enough to let the pulleys spin freely, and the nylon keeps the nuts from backing out. The motor slides in from the back and is secured with three M3 bolts. With the motor in place, I attached the 60T pulley along with the timing belt. After adjusting the position, I tightened it down using a grub screw on the side. Mechanically, we’re all set.

Time for a test! I connected a 12V DC power supply, and just like that - smooth, clean rotation. Everything is running perfectly. I’m honestly thrilled because this design doesn’t leave much room for adjustment. All that careful measuring and prep work totally paid off in the end.

To give the machine a stable base, not just sitting on a thin plywood edge, I glued it onto a thicker 18mm plywood platform. On the back, I found the perfect spot to mount the electronics. I used some CA glue to fix four 3D-printed risers in place. These hold the PWM speed controller. It only costs a few bucks, but it gives you precise speed adjustment using a just a knob. Then I designed a battery holder for a 12V Bosch cordless drill battery and 3D printed. After printing, I glued the holder in place with CA glue.

This is the concept - using a cordless drill battery as the power source. It snaps in just like on the tool and clicks firmly in place. For wiring, I used short wires with spade terminals that plug directly into the battery connector. They’re easy to disconnect, which makes battery swaps super simple. A similar setup is used for the motor, where wires are soldered on that end for a clean, solid connection. And finally, I added a foot pedal switch. That’s the last piece in the control setup, giving me hands-free on/off control while keeping both hands on the wire during use.

The speed controller adjusts how fast the motor spins, and the pedal acts as a simple on/off switch. This way, I can hold the wires with both hands and start or stop the machine just by tapping the pedal with my foot - super convenient when you're mid-process and need total control.

The final missing part gets installed here. Secured over a drilled hole using an M6 bolt, a couple of washers, and nuts. I’ll be using cloth electrical tape for wrapping. It sticks really well but still peels off cleanly. To hold the tape roll, I designed and 3D-printed a two-part adapter that sandwiches it from both sides. Now the roll slides right onto the bolt and locks in place with a nut, ready to spin freely when the device runs.

And finally - the wrapping moment we’ve all been waiting for. I stuck the end of the tape down, pressed the foot pedal, and the machine spun up smoothly. All I had to do was guide the wires in and let it wrap. It laid them out cleanly with perfect spacing. I could even pause, add more wires, and keep going. Honestly, I’m stoked with how well it works. What do you think? Can I call it well done? Drop your thoughts in the comments, and I’ll see you next time!