A Simple Clock
Introduction: A Simple Clock
In this coronavirus lockdown, I came back to my hometown. Everything is good here but there was one small problem. There is no clock on my table. I know a table clock sounds a little redundant especially in this era of smartphones and laptops, but it's always good to have one. Also, it is irritating when you are doing some work or watching any series on full screen and have to scroll up or fetch for the phone just to check the time.
My old table clock is kept in my dormitory. I took it last year when I joined college and forgot to buy a new one for home. I thought of making one by myself but I always kept averting it in procrastination. A few days ago, Instructables launched a clock contest and I thought, now would be a good time to make a clock.
About the clock I made, it's a very simple clock that shows time and date. To be honest, I only wanted a time-keeping device that can tell hour and minute but I also included the date as it's good to have it visible. Apart from that, I don't need anything else. All those features like a stopwatch or timer are meaningless for a table clock. Anyway, we can use our mobile phones for those special scenarios when we need them.
How does it work?
There are four 7 segment displays that will work in synchronization to display time. Every 10 seconds, the current date will be displayed for a period of 3 seconds. On the right-hand side, there are three indicators for AM, PM, and date. They are there so that one does not confuse the date with time. A push-button is also present for the date, just in case you want to check it and do not want to wait for it to appear.
Note: At the time of making this Instructable, a very strict lockdown is going on in India (because of Covid19). Only essential commodities are available. Therefore, I am restricted to use things that I have in hand. Spare me for taking shortcuts or for not doing things professionally. I am bounded not by will but by means.
Supplies
* Arduino board (preferably nano or mini)
* RTC module (DS1307)
* 74HC164
* LED strip (I am using 2835 white)
* NPN transistors (BC547) X15
* High current NPN transistor (2N2222) X4
* 1K ohm resistors
* Headers
* Push buttons
Step 1: Print the Parts
This project is heavily dependent on 3D printing. The basic structures as well as the outer casing are made from 3D printed parts. One can surely make it without a 3D printer but it would be a lot hectic and definitely not worth your time.
I have designed all the parts in TinkerCAD software. I am not a design guy and TinkerCAD gives me just enough flexibility to make 3D models. 288
Links to all the files can be found below.
Three things I want to point out here:
1. Print the internal parts/sleeves in a dark or dense filament so that the light cannot wander inside and ruin the look.
2. Try to print the outer casing in the black filament. It looks good. I did not have a black filament so I printed it in Fuschia and colored it with spray paint.
3. Since the outer casing is too large to be printed at once, I have sliced it into two parts. This creates a weak joint in our 3D printed model. Instead of using a 3D printed backplate, I am using a single-piece MDF board for the back, to overcome it. This provides some stability to the side casing. It is just a precautionary thing, not a necessity. I have still provided a design for the backplate.
Point to be noted, sleeves are the extended covers printed to guide the light. They are a bit fragile because they are made from 1mm thick walls. The reason for it being so thin is that they are just providing a boundary to light rays. Apart from that, they don't have any special purpose so it is not wise to spend excessive material on them. Another reason is thinner walls are easier to bend. This property helps in attaching them to the base plate. If they don't fit properly, just slightly bulge them and they will form a perfect fit without deforming the top layer. A thicker wall will cause the entire structure to bulge.
Apart from the right-side panel, no other part needs support. Build plate adhesion is also not required, you may skip it. I printed all my parts without it and they turned out fine. Anyway, it's your call. For joining two side covers, I am using 2 components epoxy. They have a 1mm thick guide plug to properly align them. 215