Introduction: Self-Balancing Clock
A few days ago I published an INSTRUCTABLE where I addressed the topic Resonance and proposed a device to deal with the topic during experimental activities. One of the examples I cited was about a child on a swing and how the oscillations were maintained by applying this phenomenon. In the swing the oscillations are mainly maintained by external actions (someone pushes) or the same person rocks by changing the position of some part of the body every certain regular interval of time. While working on that project, I came up with the following idea: The Mechanical Clocks also change the geometric arrangement of their mass during operation, will they be able to rock in a similar way as a child does on a swing? The previous idea motivated me to develop this project.
In this INSTRUCTABLE I propose the steps for building a Self-Balancing Clock. I think that with the proposed steps, it will be quite simple to be built. Other creative applications can also be derived from the ideas discussed. Hope you like it!
608RS Bearing extracted from a Fidget Spinner
2 x 6mm Wood sheets or Plexiglass Sheets
CNC Router with 1.5mm Endmill, Laser Cutter or 3D Printer
50g Weight or another weight could work (Coins etc).
Clock Mechanism and battery
M8 Bolt and Nut 30mm long
4 x M8 Washers (12mm external diameter)
Permanent black marker
Step 1: Extract a Bearing From the Fidget Spinner
After several tests with other bearings, I decided to use the ones used in Fidget Spinners. These bearings are designed to have minimal friction. They have excessive gaps (they look worn) and do not include lubricating greases. Each Spinner has four bearings, please select the one in the center. With a non-metallic hammer or with the handle of a screwdriver, hit the bearing until it comes out of its cavity. Check that it rolls with low friction and do not add any lubricant to it.
Step 2: Cut the Pieces on the CNC
In this step, all the pieces that will form the Clock assembly must be cut. With a 1.5mm EndMill cutter run the G-Code files included in your CNC machine. Verify that your machine has a working area of at least 200mm width (X coordinate) by 300mm depth (Y coordinate). Declare the coordinate origin at the bottom left of the 6mm thick Wood Sheet.
Additionally, the files are included in DXF format, with them you can also cut the pieces in a Laser Cutter, you could even print the vector drawings on paper in an ink printer, glue these sheets of paper to the Wood sheets and using classic tools cut them.
STL files will also help you reproduce the parts on a 3D printer, in case that is your best option.
Step 3: Sand, Highlight and Paint the Pieces
The two pieces that make up the Support must be glued before undertaking this step. It is not absolutely essential, but I consider it appropriate before painting since the applied paint could interfere with the coupling.
With a permanent black marker highlight all the marks on the watch face and scale. Try as much as possible not to paint other areas than these. Wait a few minutes and using the sander, sand the pieces until only the desired areas are highlighted in black and there are no ridges. Optionally, paint the pieces with varnish and let them dry for 12 hours.
Step 4: Mechanically Assemble the Components of the SELF-BALANCING CLOCK
Insert the bearing into the hole of the Support first and apply a small amount of Super Glue, just to lock it in place. DO NOT ALLOW GLUE TO ENTER THE BEARING INSIDE. Then, glue the Screw Bezel to the hexagon and allow it to dry. Through the central hole of the Balance Arm place the screw and washers as shown in the image. Insert this assembly through the Bearing on the Bracket. With the remaining washer and nut secure the entire assembly. DO NOT OVER TIGHTEN THE JOINT.
Also, attach the Clock Mechanism to the Balancing Arm by inserting it through the hole and fixing it with its nut. Verify that the base of the Clock Mechanism is parallel to the Arm.
Step 5: Prepare the Weighing Pan
I recommend sticking the weight of 50g in a fixed position on the Weighing Pan, this will make it easier to balance the Clock horizontally when you put the hands in the 12:00 position. Cut three ropes approximately 15 cm in length and tie each one at the ends, so that when you insert them through each hole of the Weighing Pan they do not come off.
Step 6: Add Extra Weight to the Minute Hand
In an ideal super-low friction system, it would not have been necessary to add extra weight to the hands of the Clock Mechanism. In order for the imbalance to be perceived, around 1g of extra mass should be added to the minute hand, distributed in a pattern similar to the one shown in the image. Small nuts or bits of metal could be used for this purpose. Glue them with Super Glue and allow the joint to dry. You can try adding extra weight to the Hour hand as well. Check that they do not interfere with the movement of the remaining hands and that the extra weight has not been exceeded.
DO NOT ADD EXTRA WEIGHT TO THE SECONDARY NEEDLE.
WHILE FURTHER THE EXTRA WEIGHTS OF THE CENTER OF THE NEEDLE ROTATION AXIS ARE PLACED, THE DEVIATION OF THE BALANCE ARM WILL BE GREATER DURING OPERATION, HOWEVER, IT MAY ATTEMPT WITH THE PERFORMANCE OF THE CLOCK (STOP OPERATING).
Step 7: Final Assembly and Calibration
Place the hands on the Clock Mechanism and set the time 12:00, moving the rear adjusting wheel. Place the Clock battery with a small piece of electrical tape or cardboard in one of its electrical contacts to prevent the Clock Mechanism from starting. Now insert the three threads holding the weighing pan through one of the holes in the Balance Arm (where the position of the Balance Arm is best adjusted to the horizontal position). It may be necessary to add extra weight until the arm is horizontal. Verify that the whole set can be freely balanced. Remove the insulation from the electric battery and insert it back into the Clock.
This step concludes the construction of this project. I hope you liked it and start making your own version. Can you imagine building a much bigger one with much stronger Clock mechanisms and larger displacements? Wow! I'd also like one like that, I'll also think about it.
Don't forget to check out my other projects. I will be aware of your comments and suggestions. Good luck!
Participated in the
2 years ago
What a great idea! Thank you for sharing your work :-)
Reply 2 years ago
I'm glad you liked it. Thanks for your comment.