Cordless Drill Cut in Half - Cross-section Display Piece by Hand

If you obsess over the mechanics of everyday items, this project is for you.

I found a broken brushless Milwaukee drill in the trash. I took it home to repair it, but noticed it was in very poor condition. It was wrapped in Milwaukee tape, so I assume it was sent to be repaired and returned due to prohibitive repair costs, then discarded.

I sat on it for a while but couldn't bring myself to throw it away. Then the eureka moment struck. If it's not worth repairing - so be it!

I must credit Mikeasaurus. Almost a decade ago he published a book about cutting everyday items with a waterjet machine. I'm fairly sure the idea has been sitting in the back of my mind, as I came across it back in the day. Doing so by hand, however, is a serious challenge.

This Instructable has been entered in the Visualize it contest. I am a student, studying Mechatronics.

Watch the #shorts video!

Tools (affiliate links)

1. Angle grinder / eBay
2. Belt sander / eBay
3. Torx bit set / eBay
4. Various hand tools

Materials & Consumables

1. A broken brushless cordless drill (out of luck? Try Facebook Marketplace / eBay)
2. A stand / make your own
3. Clear silicone adhesive
4. CA glue / eBay
5. Spray lubricant

I had found it originally with chuck assembly disassembled, and did quick work of the rest, separating the rotor, stator, speed controller, circuit board (heat sink) and other various parts. I cut most of the wires as well.

Take special notice of the orientation of every part to avoid attempting to adjust parts during reassembly which could turn others out of the proper alignment.

The secret to cutting round parts is to cut less than halfway through, so they remain intact. This is especially true of the chuck, which contains tons of small parts. I was very careful to avoid going too far, as reassembling it may not be possible onece it's split apart. I lost a bunch of tiny bearing balls, but decided to deal with that later.

I was concerned about the wires in the stator unwinding while cutting, so I put a few drops of CA glue between them.

Gearboxes are packed with many small gears that can be unpredictable. I didn't cut very deep into it. In hindsight, it would look best if the casing were cut with the individual gears being left intact. I'm not sure how that could be done.

I left the PCB intact. I like the contrast between the gold coating on the green PCB and the rest of the drill.

Cutting different parts to different depths gives it an awesome 3D look.

Grind the parts to their final shape, making sure not to go too far - keep everything intact!

This is the chance to bring bolts and other threaded parts precisely to their cross sections (which is just mesmerising, in my opinion).

Avoid grinding any solder joints as they may contain lead.

Cutting the rotor was a challenge that ultimately failed. It's constructed of thin steel layers with strong neodymium magnets in between.

The steel layers warp and fall apart from the grinding wheel, the magnets melt and attract metal dust, making a mess, and the bearing is too small to be cut properly.

Luckily, since I destroyed only half, I flipped it around to hide the failure.

I degreased and washed the housing and parts, reassembled it, and glued everything in place as well as two of the bearing balls in the chuck. I gave the steel parts a thin coat of oil to prevent rust.

I cut away part of the trigger housing carefully to expose the mechanism inside while ensuring its structural integrity. It can still be pressed normally!

I didn't have a battery, so it needed a stand to stay upright since it's very top-heavy. I bolted a small steel plate to the bottom. Since I keep it on display above eye level, it won't be visible, but I gave it a coat of spray paint for good measure. If yours has a battery, it's best to open it carefully and dispose the cells safely.

I genuinely didn't expect it to turn out this good!

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