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Wanted: A Simple Lap Counter

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  • Wanted: A Simple Lap Counter

    I picked up a small used Max Trax oval. It came with light sensors hooked up to a printer cable. I assume that's for a Trackmate-type system and needs an overhead light source.

    What I'd rather have is just a simple lap counter with no overhead bridge. Is there any such product out there that could be readily adapted to the MaxTrax?

  • #2
    Speak to Trackmate, as there are non-bridge hardware options, and what he does is bullet-proof and easy to use.
    Last edited by NicoRosberg.; 06-25-2017, 02:16 AM.


    • #3
      If you don't want to have a light bridge your options are to use dead strips or magnetic reed switches. It would be difficult to add dead strips to a Max Trax unless you were willing to buy a new section with the dead strips built in. It can be tricky to get reed switches to work with T-Jet type cars, but it can be done. If you have a computer with a printer or series port you can connect either type directly to those, with dead strips you would also need some resistors wired in series. If your computer only has USB ports things get more complicated. You could either get an Arduino Uno board, that has a USB output, and connect the sensors to the board. The more expensive option is to get a Trackmate interface board, the newer type has a USB output. An added advantage to using the Trackmate board is that it has connections for a track power relay and a pause control, features that would be useful if you would ever want to run races on your track. The board needs its own power supply. The board also would work with Ultimate Racer and Race Coordinator software.
      If you were to reconsider using a light bridge Trackmate sells one to fit a MaxTrax.


      • #4
        A very reliable method for triggering a lap counter is called a 'dead strip'. It is a short section of track where the power conductors are isolated from the rest of the track -- no power.

        The power conductors for each lane are wired up to an electronic lap counter. When a car passes over the dead strip it completes the circuit between the two power conductors, which signals the lap counter to record a lap.

        Dead strips are usually located on long straightaways so the cars can coast across them without any issues.

        Often one set of power conductors are wired together ('commoned') to a single terminal on the lap counter, while the rest are wired to individual terminals.

        I have used dead strips on all of my tracks. For HO cars a dead strip 4 inches long (10cm) works very well.

        Finding a lap counter that is suitable for use with a dead strip may require some research. But since dead strips have been in use since the very first days of slot racing, they are out there.

        I own a vintage 4-lane TrikTrax lap counter, which was designed for use with a dead strip. Unfortunately they are no longer made, but are considered one of the best non-computer-based lap counters ever produced. The TrikTrax units have two operating modes -- lap counting and lap timing. Lap timing is to a thousandth of a second -- you don't need anything better than that!

        On rare occasion TrikTrax units can be found for sale used. A used TrikTrax is a good investment. They seem to last forever, and are always sought after.

        If you choose to go the computer route, there are ways to set up computers to work with dead strips. I can't advise you there, however, since I have never set one up. There are other folks on this forum who have, and should be able to give you advice.

        Ed Bianchi

        PS - Way back at the dawn of time Aurora made an electric two-lane lap counter for use with a dead strip. It used solenoids to ratchet numbered wheels to count laps. In this case the 'dead strip' was powered -- when a car completed the circuit there had to be enough current to operate the solenoid. I added some extra power by wiring a 6-volt battery in series, so the car would not slow down over the 'dead strip'.

        Those Aurora units were not very reliable. Some might still be around, but I would not recommend them for use these days.
        Last edited by HO RacePro; 06-25-2017, 01:03 PM.


        • #5
          I have a Max-Trax 6 lane layout with dead strip and a Trix-Trax counter/timer which has always been
          very reliable.


          • #6
            Trackmate works with dead-strips, and they will make them.


            • #7
              My MaxTrax has dead strips. You can connect those to a computer with serial or printer ports, but certain precautions must be taken or you could burn out a port. I also used a TrikTrax counter and that worked great, the necessary circuitry is built into the unit. The drawback to a TrikTrax (besides being out of production for years) is that it can't manage races like a computer based system does. If you only have a computer with USB ports life gets more complicated. Trackmate has a dead strip option that includes extra parts that keep track power away from your electronics and short circuits from burning out your ports.
              Here is an article with more information on dead strips:


              • #8
                My request was for a simple lap counter. In my book, that means closer to the old Aurora counter than anything related to a computer.
                The Trik Trax is closer, but the last one on the market went for $325.
                Where is that fat guy in the basement the POTUS talked about? Couldn't he be building a simple digital lap counter? Or how about a dead strip adapter for the AFX digital lap counter?

                Speaking of dead strips, MaxTrax does make one for $130. My bargain track was only $200. I'd like to keep it a bargain.
                To that end, does anyone know how the rails are held in MaxTrax? Is it as simple as the colored plastic piece holding the rail in place by a press fit in the groove?


                • #9
                  This may be more in the line of what you thinking... This shows a timer, but the same could be done with a lap counter...RM



                  • #10
                    Oh if Hornby only made ARC for Micro...


                    • #11
                      You always have the option to roll your own. How about US$17.50 per lane, plus your own skull sweat, mounting and wiring?


                      It takes at least 10 volts DC to trip this counter -- you have to provide that. Also, since this unit can count up to 40 counts per second, you may need to 'debounce' the input so it doesn't count more than one lap per pass over the dead strip. Could be done by adding an electromechanical relay or a capacitor/resistor delay into the circuit.

                      Sound complicated? Here's your chance to expand your skill set!

                      Ed Bianchi
                      Last edited by HO RacePro; 06-26-2017, 04:06 AM.


                      • #12
                        Sorry about that! I assumed that you wanted to use the sensors that were already built into the track if possible. The easiest thing to do is to download a cell phone/tablet app. You would have to make a bracket to hold the cell phone, possibly by adapting a selfie stick.

                        The latest MaxTrax have T shaped slots for the rails. The rails are L shaped and are held in place by the plastic tubing that also serves as the color coding, like so:

                        The older track uses plain rails, I don't know if it was also glued in place, but the rails on my track have never pulled up.


                        • #13
                          For a simple lap counter, we took 2 of those overhead afx lap counters and cut one leg off each, and hot glued them to the table. Only counts up to 50 though...


                          • #14
                            A MaxTrax is much wider than standard plastic HO track, getting the AFX counters to work would probably involve more cutting and splicing.
                            If you are racing you need a lap counter, but if you are practicing or trying to tune your cars a lap timer is nice to have. Computer based systems can do both functions at once, the TrikTrax toggles between counting and timing.
                            Last edited by RichD; 06-27-2017, 09:39 AM.


                            • #15
                              dead section
                              works great, does not matter about track width.

                              with a computer system. you only need about an inch, the old 3" concept is not needed.

                              That is based on my testing. I even tried 1/2 inch with issues