0.5$ : Measuring Tool and Stress Reliever

Hello, Friends!

Let me present a short report on creating a highly budget-friendly tool. Not only is it useful for various tasks, but it can also serve as a stress reliever! And here’s the kicker: making this tool cost me only $0.50.

1. A piece of 4mm thick brass sheet
2. A screw with a coupling nut
3. A miniature bearing
4. Spray paint
5. Quick-drying glue

First, I prepared the blank for lathe processing. To simplify the task, I glued the brass blank to a part I found in my scrap box—something with the right diameter. I used quick-drying glue for attachment. Of course, this isn’t the most professional approach; ideally, I’d have made a custom fixture. However, for a one-off project like this, it wasn’t worth the effort.

Using my vintage lathe, I machined the brass blank to a precise diameter of 47.7 mm, checking constantly with calipers. Achieving the exact diameter was critical. I finished by smoothing out any burrs with a file for a polished, smooth surface.

To enhance the coin’s appearance, I added fine grooves (known as reeding) to its edge. These grooves not only improve the aesthetic appeal but also provide extra grip for various tasks.

(Side note: My lathe makes a lot of noise, but oddly, this doesn’t bother my cat, who loves napping under my desk lamp during these sessions. Perhaps she’s off exploring unseen dimensions...)

Using a homemade tool, I found the exact center of the blank. To ensure clarity, I marked the presumed center with a red marker. Then, I carefully made shallow scratches to confirm the center point.

Next, I prepared for milling by securing the blank to a flat steel plate with quick-drying glue. I’ve tested this method before—it’s more than adequate for precise and stable milling work.

After milling, I removed the cutout, resulting in a 9mm diameter hole. While drilling might have been an option, I didn’t have the correct size bit on hand.

To refine the surface, I sanded the brass with fine-grit sandpaper. Brass is soft and doesn’t show major scratches, making it easy to polish. For hand sanding, I recommend sandpaper with a fabric backing—it’s sturdy and easy to handle.

I inserted a micro-bearing into the hole. Before installation, I removed the manufacturer’s grease from the bearing by rinsing it in gasoline or kerosene.

After pressing in the bearing, I applied matte black paint into the grooves, using paint designed for tough conditions. Any excess paint was wiped away with a cloth dampened in gasoline.

For the finishing step, I installed a brass screw with a coupling nut into the bearing’s central hole. The screw’s height matched the coin’s thickness (4mm), and the nut’s diameter matched the bearing’s inner diameter (5mm). These screws are commonly used for making belts or dog collars, making them easy to source.

The result is a functional tool: a circular ruler for measuring curved distances. This coin-ruler is handy for tasks like sewing patterns or small-scale construction projects. Moreover, it doubles as a fidget coin, a stress-relief toy. Spin it with some force, and it’ll rotate smoothly for a while, thanks to inertia.

The project’s total cost was just $0.50, which went toward quick-drying glue. Everything else was salvaged from materials I already had lying around.

Thank you for your attention. May your creative inspiration always be with you! 😊

Anton Pisarev (A_Craft)