Bicycle Clock (with Unscrew-able Clock Mechanism)

This project entails creating a bicycle clock with a bike wheel and a quartz clock mechanism, that can also be unscrewed to separate the clock from the wheel. (for full product look at image 1, for unscrewing look at video 4). I used a laser cutter to cut all the parts of the clock (the gear part, the numbers, and the spanner clock hands (images 2 & 3)) and Techsoft 2D to design all the parts. I printed them in acrylic plastic material.

The bike wheel is 62cm in diameter without the tire. The clock mechanism is attached to the clock part that looks like a bike gear with 12 spikes. Each spike represents one hour of the clock, which consequently has transparent acrylic numbers on it. This clock mechanism and gear part can screw on and off of the bike wheel so that you can easily change the battery (watch video 4). The clock hands have silver spanner cutouts glued to them. You can hook the product to the wall simply by hooking it on to the wires of the bike wheel.

Step 1: Designing With Technical Drawings and CAD Files

The first step is to design the parts of the clock through technical drawings and CAD files.

At first, I was going to design my product differently; I was going to put a wood-stained plywood background to the wheel, and instead of a gear part covering the clock mechanism I was going to use a simple circle cut out of plywood with enough space to let the clock hands stick out. This design is illustrated in the first image attached, the technical drawing.

When I changed the design, I made only technical drawings. The second image is a very simplified version of my product, it just shows the basic idea of the product.

The third image shows how the gear part covering the mechanism will look. The gear part was approximately 16cm in diameter.

The fourth image shows how the clock hands will look, inspired by traditional spanner tools. The spanner cutout clock hands will be approximately 8cm in length.

The fifth image is a more detailed CAD file of the second image. It shows how my product will look when all the parts are together. Obviously, I am not laser cutting the bike wheel, but in this CAD file, I showed the bike wheel so that I could visually display how all the parts would work together.

The sixth image is a CAD file of only the parts I will laser cut. It shows the gear part, the numbers for the clock, and the spanner parts that I will attach to the clock hands.

There are also two circular cutouts that were laser cut in 3mm plywood, but these aren't in the CAD files. The size of these depend on the size of the empty gap in the center of your bike wheel, and of the length and size of your screw (more clearly explained in step 4).

Step 2: Getting the Bike Wheel Ready

The bike wheel

I got my bike wheel from one of my dad's old bikes in our garden shed (image 1). The first thing I did is cleaned it with a sponge with soap and water to get all the dirt and leaves off. Then I took the tire off by deflating it and then pulling it off. In images 2 and 3 you can see the bike wheel with the tire taken off. Then, in the middle of the bike wheel where all the metal wires connect to, there was a long screw with other small parts (image 4). I took these all out, which was quite a messy job because there was grease all over them. In image 5 you can see the middle of the bike wheel is empty and you can see through it, this is where all those small parts were before. You can throw all the small parts away except the long screw (I accidentally threw mine away so I had to find an alternative, but its best if you keep it and clean it). Then, your bike is ready to be used as in your product.

Step 3: Gluing the Gear Part With the Numbers

The next step is to print and construct the parts.

Like I mentioned previously, I printed most of the parts of my clock in acrylic plastic material with a laser cutter. I printed a bike gear cut out in black acrylic, clock numbers in transparent acrylic, and the spanner cutouts for the clock hands in silver laminate material (lightweight plastic).

The first thing I did was take a ruler to measure a straight line along one of the spikes of the gear part. This would tell me where '12' would go, and then I could glue the numbers on straight, not slanted and sloppy. I used a whiteboard marker for this (image 1). Then, I glued the clock numbers to the gear part. Each spike is for a different hour of the clock, so I glued them on accordingly. I used epoxy-resin glue to attach the transparent numbers to the bike gear. I let the numbers dry for around an hour to make sure they were stuck on well.

Step 4: How to Screw the Clock Mechanism to the Wheel

To be able to screw the clock mechanism on and off the bike wheel, I needed a long screw and two small circular cutouts that were printed in 3mm plywood. Both circular cutouts fit in the empty gap in the center of the bike wheel but they were different; one of them was to stop the screw from sliding back and forth in the empty gap, the other was to screw onto the clock mechanism. Therefore, the one to stop the screw from sliding has a circular hole, and the one that was to screw the clock mechanism on had a hexagonal hole.

The circular cutout with a hexagonal hole had a hexagonal nut that I glued to the hole (image 2). I glued it with epoxy-resin glue, and let it dry for around one hour. This hexagonal nut fit onto the top of the screw, which meant I screw it on and off. The screw had a circular rim, which is why the other circular cut out needed a circular hole, and the hexagonal nut had a circular hole which screwed on easily to the screw. Then I glued the hexagonal nut + the circular cutout, which were now one piece, to the back of the clock mechanism (image 1). This meant that the screw, with a circular rim, could screw on and off of the hexagonal nut + circular cutout + clock mechanism, which were all now glued together, so that I could change the battery.

The other circular cutout, the one with a circular hole in the middle, was placed between the end of the screw and the beginning of the empty gap in the center of the bike. This was to stop the screw from sliding in the empty gap since the screw was slightly longer than the empty gap. (Images 2 and 3).

Look at video 4 to see how the clock mechanism screws on and off of the bike wheel.

Step 5: Gluing the Clock Hands

Once the clock mechanism could screw onto the bike wheel, and the numbers were glued onto the gear part, all that was left were the clock hands.

Like I mentioned previously, I used a quartz clock mechanism with came with clock hands shown in image 2. Once the clock mechanism + gear part was screwed on to the bike wheel, I could push on the clock hands onto the spindle. (First the shorter hour hand, then the longer minute hand).

Then I used epoxy-resin glue to glue to spanner cutouts onto the clock hands. Obviously, the shorter spanner cut out was glued to the hour hand, and the longer one to the minute hand. When gluing them I had to hold them in place for a few minutes to make sure they didn't slide off. I glued them so that the curved ends of the spanner clock hands surrounded the center of the clock where the spindle came out of (image 1).

However, I started out with relatively long clock hands, as you can see in image 3. These looked better, but they were too heavy and wouldn't let the actual clock hands of the clock mechanism turn, they would weigh them down. So I had to shorten them until they wouldn't cause any problems with the function of the clock.

Step 6: You're Done!

Now you're finished the bike-clock, with an unscrewable clock mechanism. You can add a hook to the back, or use the wires to hook it onto the wall like I did.

Hope you enjoyed and found this product design useful!!

Let me know if you try this idea out :)

- Ana