Building one of something is tremendously easy. If you’re making one of something, you can cover the insides with hot glue, keep everything held together with duct tape, and mess around with it enough that it mostly works most of the time. Building more than one of something is another matter entirely. This is the thought behind DFM, or Design For Manufacturing. [Nick Sayer] is an experienced seller on Tindie and he’s put together enough kits to learn the ins and outs, rights and wrongs of building not one, but an inventory of things. Check out this last talk of the 2015 Hackaday SuperConference, then join us below for a bit more on the subject.
[Nick]’s hobby come business is called Geppetto Electronics, where he manufactures everything from battery eliminator boards for Apple’s Magic Trackpad to replacement electronics for the ubiquitous AA-powered quartz clock movements that make time go slightly wonky. He has the street cred and has produced enough random electronic doodads to know what he’s talking about, and while [Nick]’s talk only covers the basics, there are a lot of good tips.
This is not a talk about sitting at a kitchen table with a soldering iron, reels of parts, and a stack of boards. When it comes to production, [Nick] reaches out to assemblers, and that means pick and place machines. To do this you must know how assembly works. Assemblers charge by the size of the Bill Of Materials, placement count, and board/panel count. The best thing that will help any project is minimizing the size of the BOM – for most circuits, you might be able to get away with completely ignoring the difference between a 220Ω and 330Ω resistor. If you can, that’s two items on the BOM that just became one. Remember resistors in series, too.
When you order a stack of boards from Seeed, DirtyPCBs, or OSHPark, an envelope comes in the mail with your boards neatly stacked on top of each other. This is not what you want if you’re making hundreds of things. You’ll need to panelize them, and that means following the assembler’s instructions. There will be a maximum size, and you’ll need to put v-grooves or tabs in there so you can separate them later.
These are just a few tips [Nick] has picked up over the years, but by his own admission it’s not a complete accounting of the entirety of DFM. That’s fine – it was only a 15-minute talk. [Nick] did point out one of the old EEVblog videos that covers DFM in much more depth. Still, a great talk of what to do and what not to do when building an inventory and not just a project.