SMT Part Counter Aims To Ease Taking Inventory

[Nick Poole] has an interesting idea for a new tool, one that has the simple goal of making accurate part counts of SMT reels as easy as pulling tape through a device. That device is the BeanCounter, an upcoming small handheld unit of his own design that counts parts as quickly as one can pull tape through a slot. The device is powered by a CR2032 cell and and works with 8 mm wide tapes up to 2 mm in height, which [Nick] says covers most 0805 or smaller sized parts, as well as things like SOT-23 transistors.

Why would one want to make such a task easier? Two compelling reasons for such a tool include: taking inventory of parts on partial reels or cut tape, and creating segments that contain a known number of parts.

The first is handy for obvious reasons, and the second is useful for things like creating kits. In fact, the usefulness of this tool for creating tape segments of fixed length is perhaps not obvious to anyone who hasn’t done it by hand. Sure, one can measure SMT tape with a ruler or a reference mark to yield a segment containing a fixed number of parts, but that involves a lot of handling and doesn’t scale up very well. In fact, the hassle of cutting tape segments accurately and repeatedly is a common pain point, so making the job easier has value.

If you looked at the photos and suspected that the big, 7-segment numeric display is done with clever PCB fabrication options (making segments by shining LEDs through PCB layers, a trick we always like to see) you’re not alone. After all, [Nick] has a lot of experience in getting clever with board fabrication, and eagle-eyed readers may even suspect that the reset and setup buttons on the edge of the tool are created by using flex PCB segments as switches. Want the nitty-gritty details? Visit the GitHub repository for the project and see it all for yourself at the CAD level.

15 thoughts on “SMT Part Counter Aims To Ease Taking Inventory

  1. I can see some merit for this, but in its current form it’s not good enough.
    The most obvious flaw is the display. There is so much light bleeding through to the “off” segments, that I can not even read the numbers in the display in the demonstration video.

    Next improvement is to add some integrated mounting mechanism, so it can easily be fixed to some scissors or other cutting apparatus.

    This also needs some adjustment mechanism to be able to adjust to different tape widths and thicknesses.
    Thickness could be adjustable by sliding two tapers against each other. For the width, I think tape width always is a multiple of 4mm and something with a stop every 4 mm

    I also think (but am not entirely sure) the design can be improved by adding a transparent top to make it easier to see where the parts start in the tape and correlate that with the exact position a bean is counted.

    Yet another idea:
    Add an integrated clamping mechanism. Preferably one that can lock onto the holes. This makes it easier to accurately fix the tape while operating scissors with your other hand.

    I also do not understand why it would be able to count faster in “inventory mode” compared to “dispense mode”. Many microcontrollers have quadrature hardware, that can count into the MHz rates. Also, tape has a hole every 4mm, thus 250 holes per meter. Even counting at 10m per second is a very slow 2.5kHz. The only reason for the ability for not reaching 50kHz or more is sloppy design (either hardware or software).

    Just an idea: Can it count in both directions, depending on the direction the tape was put into it? This is also useful for either left / right -handed operation.

    If you want to go further, (such as for people creating kits) then re-purposing a standard SMT feeder for fully automatic dispensing and cutting tape to size is probably a better option. Especially when combined with the automatic text printer posted a month or so ago.

    1. Also:
      The exposed back with the battery has room for improvement.
      In it’s current form it’s too easily damaged by keys in your pocket or screwdrivers and what not when put in some drawer.

      The “reset” button is also in an awkward position, and forces you to use two hands to operate it. You should be able to reach it with the thumb of the hand you are holding it with. (but also not directy beneath your thumb when holding it)

      Putting the tape direction in the length of the device also makes it more ergonomic to use it.

        1. Paul does provide some constructive feedback that I think would improve the device, but I also get that starting with “it’s not good enough” comes off as cheeky and dismissive of the work that went into this project so far. I definitely agree though that the led display needs at the very least another pcb separator to try and contain light bleed as I also had a hard time reading the display.

          1. Indeed.
            I had no intention of tearing it down, but only to share some thoughts about ways this thing can be improved before it gets to the crowdfunding stage. My choice of words is more a reflection of my general state of mind then of my feelings towards some project.

  2. That’s a very helpful device. This one is nice, small and mobile. Unfortunately lacks some flexibility.
    I designed something like that a while ago: https://imgur.com/a/UIqOP0y
    It’s just a prototype and needs some improvements but still it’s more functional, can handle transparent tapes aswell as different widths and thicknesses. It’s more complicated on the mechanical side tho.

  3. As everyone else said, needs cutter

    Also, while here, why not a target mode where you pick a number to count to? Or a drive output to interface with a simple motor drive?

    Is is possible OLED screen is cheaper than segment displays now?

  4. Cannot wait to get my hands on one of these. I’ll use the hell out of it for counting stray strips with unknown bean quantities, it’s going to make taking inventory so fast. I see the merit to adding a cutter, but I’m quite glad this doesn’t include it. It’s doing one thing, and doing one thing well: counting. Killer job Nick, super stoked for this one!

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