Small Batch Manufacturing

Article
Zach Robertson

21 days ago by zachrobertson

Recently I have become obsessed with the idea of manufacturing niche products at home in a style similar to industrial manufacturing. Traditionally when you make something at home it is a one-off object that is hard to duplicate precisely, but small batch manufacturing aims to allow an average person the ability to produce a custom object reliably at home. There are many reasons you might want to do this, for me the main two are being able to make replacement parts to mass produced items for repairs, and the ability to create entirely new products either as a business or a utility for personal use.

There are also many tools you could use for this task but for me the most exciting one to make physical objects with has been a 3D printer. With a 3D printer you can reliably make an object over and over again very consistently and it’s very cheap compared to other methods. The reason for this is the material you traditionally use, the two most popular forms of 3D printing are FDM printing which can use a variety of plastics (More on this in a future article) and plastic composites or SLA printing which uses a resin that hardens when exposes to UV light. The advantage to using plastic or resin is the cost, with the main drawback being the strength of the parts and the aesthetics (3D printing will always produce artifacts and limit the shapes you can create). If the strength of surface finish of the parts you are making is very important than all hope is not lost, with the variety of CNC machines available there are many ways to make wood and metal parts with the same precision and repeatability as a 3D printer.

These tools only account for physical objects though, what about electronics? We thankfully live in an age where there is a consumer electronic device to fit any need, from the raspberry pi to the innumerable microcontrollers that exist, there is always some electronic hardware that will meet your requirements. The hard parts is deciding on the most cost effective device and having the ability to program it to do what you want it to do (I suggest you brush up on your C/C++). There is also the route of designing your own circuit boards and microcontrollers and this can be very effective at making your project smaller and more application specific. Another very exciting innovation in this area is the Index an open-source pick-and-place machine for assembling custom circuit boards, which is something I will be looking into in the future.

As an example of small batch manufacturing, here is a dash cam I made with a 3D printed case and hook for mounting on the rear view mirror of your car. Its has two ESP-32 Cam boards that have a camera module, Bluetooth/Bluetooth low energy module and WiFi module being controlled by an ESP-32 microcontroller. Each ESP-32 Cam board was its own LiPo battery and charge controller, they are both wired to a single USB-C port for charging with a two way toggle switch to control the power. When you turn it on the cameras start recording and save this video to their SD cards. They also start their own WiFi network so you can connect a phone or computer to them and view a live feed of the cameras. The firmware for the boards was written in C++ by myself and compiled using the compiler supplied by Espressif (The company who designed the ESP-32 microcontroller). The end goal for this was to have a companion Android/IOS app that you could connect the cameras with and instead of recording to just the SD cards on the cameras it would save to your phone (being overwritten every time you start a new ride unless you save it manually is there was an incident) so that there is a better chance of maintaining the video if an accident were to break the camera or your phone or if some bad actor was trying to manipulate/destroy the footage. The main point of this was not to have a dash camera for accidents but one for when you are stopped by police that is automatically recording and backing up the footage even if the cameras are tapered with. My vision was to make this dash cam cheap, open source, and easy to manufacture at home so many more people would have the opportunity to protect themselves while on the road.

Dash Cam

Thanks for reading
Zach

PS. The dash cam is still a work in progress (a slow one at that), but it will be done one day and when it is I will post about it, don’t worry ;)