Track timer made from digital watch

abahgetek Saturday, 6/9/2018

Hi… hope you have a nice day,

The idea is looking for fastest car from all my collection, not to much but I have to find the fastest car for real race with my community here, In Bandung, Indonesia.

This is the race

And this is the timer I made. Not a Bom ya...


The basic tutorial from


But I can’t find the electrical part from nearest shop here. So just take the logic and find suitable from my junk stuff.

What we need is

-          Stopwatch, i find from my junk digital watch

-          The sensor  I change with some wire for connector.

-          Reset Button, take from old electric part.

-          Electric wire

The Logic is :

-          Pull out the Start/Stop and Reset from Stopwatch/Digital watch. The Stuffs have similar function is have stopwatch timer. So just connect Start/Stop and Reset button contact to the electric wire with solder or something else. Test It.

-          In my case, wiring is like with the tutorial. From the watch have 3 wire, start/stop, reset and from battery case.

-          passing about resistor, capacitor sensor, ic in the tutorial.

-          Connect the reset wire to the battery wire trough the button take from old part. Test it.

-          Start/Stop Wire connect to battery wire to test it. If success make it parallel for start gate and finish gate. In my case I used power plug from unused computer power supply and phone wire connector to make it portable.

-          Make start gate and finish, on my creation I use plywood for Start gate and replica finish gate from PVC pipe.

-          For Start and finish gate contact, I use wire from spring. Connect with the electric wire.

 This is The Result :







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3DBotMaker 7/20/18

Nice. I've seen that Makezine article. Any footage of it in action?

  • I do not yet take picture on action. Thanks for comment. This timer sometimes error caused by double touch on finish, timer will pause and start again if double touch and the gate to strong if the car not speed enough. This project not continue yet, i dont have time for it right now. I have to find way to solve it. But for next project finish gate i will learn use arduno, like yours maybe. — abahgetek
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