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Pinewood Derby Timer

PDT Pages

Main Page
Shield PCB
Timer Builds
PDT Arduino Uno


The Pinewood Derby Timer (PDT) is an Arduino based track timer. The robust and flexible design allow the PDT to be easily constructed and modified to meet your specific needs. Features of the PDT include:

- Easily expandable from 1 to 6 lanes
- Supports (optional) solenoid start gate circuit
- Supports (optional) lane place/time digital displays
- Works standalone or can be interfaced to software running on a PC
- Supports lane masking, start gate status check, force end of race

Interfacing the PDT to software running on a PC allows races to be managed and allows you to record and archive car run times as you test and tune your Pinewood Derby car(s). Currently compatible with the following software:

- Free PD Test/Tune/Track (PDT3) software utility (see below)
- The popular Grand Prix Race Manager software


This PD Timer zipfile contains the timer code (Arduino sketch), hardware schematics and user documentation. The individual items can also be downloaded:

- hardware schematics
- timer code (Arduino sketch)
- user documentation.

The PDT3 setup program will install the PD Test/Tune/Track utility software.

The original version (revision 1) of PDT can be downloaded here: PD Timer - revision 1.


The Arduino based timer is both flexible and affordable. Components for the base configuration (no displays, supporting only one lane) will cost approximately $30. Finish sensors/LEDs for additional lanes will run approximately $1-3 per lane. An implementation of the timer is shown in the picture below:

PDT timer custom PCB shield

Bare Shield PCBs Available for Purchase - visit the Shield PCB page for more information.

An implementation of the PDT on a two lane BestTrack is shown below:

Start System (Optional)

The optional start gate circuit utilizes a solenoid to remotely trigger (via software or a trigger switch) the start gate of the Pinewood Derby track. Components for this system will run approximately $10 (not including a DC power supply for the solenoid). The following picture shows one installed on a BestTrack track:

PDT solenoid start system

Lane Place/Time Display (Optional)

The optional lane place/time displays utilize a LED driver and 7 segment LED displays to show the finish place (1st, 2nd, 3rd, etc.) and time for each lane. The display and driver board cost approximately $10 per lane, one is shown in the photo below:

PDT solenoid start system

PD Test/Tune/Track Software Utility

The PD Test/Tune/Track (PDT3) utility is a software program that fully interfaces with the PDT and allows you to record, analyze and archive car run times during the testing and tuning process of building a Pinewood Derby car. The main screen of the PDT3 utility is shown below:

PDT3 utility screenshot

Refer to the user documentation for full configuration and usage instructions.


The timer code (Arduino sketch) and hardware schematics are licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ or send a letter to Creative Commons, 444 Castro Street, Suite 900, Mountain View, California, 94041, USA.

Last updated: 28 February 2013