Learn What Did and Didn’t Work In this Prototyping Post-Mortem

[Tommy] is a one-man-shop making electronic musical things, but that’s not what this post is about. This post is about the outstanding prototyping post-mortem he wrote up about his attempt to turn his Four-Step Octaved Sequencer into a viable product. [Tommy] had originally made a hand-soldered one-off whose performance belied its simple innards, and decided to try to turn it into a product. Short version: he says that someday there will be some kind of sequencer product like it available from him, “[B]ut it won’t be this one. This one will go on my shelf as a reminder of how far I’ve come.”

The unit works, looks great, has a simple parts list, and the bill of materials is low in cost. So what’s the problem? What happened is that through prototyping, [Tommy] learned that his design will need many changes before it can be used to create a product, and he wrote up everything he learned during the process. Embedded below is a demo of the prototype that shows off how it works and what it can do, and it helps give context to the lessons [Tommy] shares.

Continue reading “Learn What Did and Didn’t Work In this Prototyping Post-Mortem”

Erika Earl: Manufacturing Hacks

Many of us will have casually eyed up the idea of turning a project into a product. Perhaps we’ve considered making a kit from it, or even taking it further into manufacture. But building a single device on the bench is an extremely different matter from having a run of the same devices built by someone else, and in doing so there are a host of pitfalls waiting for the unwary.

[Erika Earl] is the Director of Hardware Engineering at Slate Digital, and has a lengthy background in the professional audio industry. Her job involves working with her team to bring high-quality electronic products to market that do not have the vast production runs of a major consumer electronic brand, so she has a lot of experience when it comes to turning a hacked-together prototype into a polished final device. Her talk at the 2017 Hackaday Superconference: Manufacturing Hacks: Mistakes Will Move You Forward examined what it takes to go through this process, and brought her special insights on the matter to a Hackaday audience.

She started her talk by looking at design for manufacture, how while coming up with prototypes is easy, the most successful products are those that have had the ability to manufacture as a consideration from the start of the design process. Starting with the selection of components, carrying through to the prototype stage, and through design reviews before manufacture, everything must be seen through the lens of anyone, anywhere, being able to build it.

At the selection of components for the Bill of Materials level, she made the point that high quality certified components can be the key to a product’s success or failure, contributing not only to reliability but also to it achieving certification. In her particular field, she often deals with components that can be close enough to the cutting edge to be prototypes in their own right. She mentioned the certification angle in particular in the context of exporting a product, as in that case there is often a need to be able to prove that all components used to meet a particular specification.

When it comes to the prototype stage, she made the point that documentation is the key. Coming back to the earlier sentence about anyone anywhere being able to build the product, that can only be achieved if all possible stages of manufacture are defined. She mentioned an example of a product in which the prototypes had had PCB fixing screws tightened by hand; when the factory started using electric screwdrivers the result was damaged PCBs and broken tracks.

The design review should look at everything learned through the prototype stage, and examine everything supplied to the manufacturer to allow them to complete their work. She describes finding support documentation containing a poorly hand-drawn schematic, and seeing an electronic assembly in which a piece of gum had been used to secure something. She also made the point that another function at this point is to ensure that the product is affordable to produce. If any parts or procedures are likely to cost too much, they should be re-examined.

After the talk itself as described above there is a Q&A session where she reveals how persistent and cheeky she sometimes has to be to secure sample parts as a small-scale manufacturer and delivers some insights into persuading a manufacturer to produce prototypes at a sensible price. And yes, like most people who have tried their hand at this, she’s had the nightmare of entire runs of prototype boards returned with a component fitted incorrectly.

The talk is embedded in its entirety below the break, and represents an extremely interesting watch for anyone starting on the road to manufacturing, particularly in the electronic world. If this describes you, take a look!

Continue reading “Erika Earl: Manufacturing Hacks”

Sacrificial Bridge Avoids 3D Printed Supports

[Tommy] shares a simple 3D printing design tip that will be self-evident to some, but a bit of a revelation to others: the concept of a sacrificial bridge to avoid awkward support structures. In the picture shown, the black 3D print has small bridges and each bridge has a hole. The purpose of these bits is to hold a hex nut captive in the area under the bridge; a bolt goes in through the round hole in the top.

Readers familiar with 3D printing will see right away that printing the bridges might be a problem. When a printer gets to the first layer of the bridge, it will be trying to lay filament in empty space. By itself this is not usually a problem as long as a bridge is short, flat, and featureless. Unfortunately this bridge has a hole in it, and that hole means the printer will be trying to draw circles in mid-air, rather than simply stretching filament point-to-point across a gap. One solution would be to add a small amount of support structure, but that just moves the problem. Removing small supports from enclosed spaces can be a real hassle.

To solve this [Tommy] added what he calls a “sacrificial bridge”, shown as blue in the CAD image. He essentially gives the hole a flat bottom, so that the printer first lays down a thin but solid bridge as a foundation. Then, the portion with the round hole is printed on top of that. With this small design change, the print becomes much more reliable with no support structure required.

There is a bit of post-work involved since each hole needs to be drilled out to punch through the thin sacrificial bridge underneath, but it definitely beats digging out little bits of support structure instead.

Nick Sayer: Making 10ⁿ Isn’t The Same As Building One

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.

Continue reading “Nick Sayer: Making 10ⁿ Isn’t The Same As Building One”

[Bunnie Huang’s] Hardware Talks Top Your Watch List

When [Bunnie] talks, we listen. He is a fount of product engineering knowledge, having seen many of his own products through from concept to market, and frequently helping others do the same. Of course having the knowledge is one thing, but he is also an accomplished speaker who knows what is important and how to share it in a way which is meaningful to others. The latest example of this is a pair of Engineering Talks he gave at Highway 1.

It’ll take you less than twenty minutes to get through the two videos. The first focuses on documentation for manufacturing. What do you need to include on a bill of materials sent to the factory? [Bunnie] has a set of gotchas which illustrate how vital this is. He also discusses how to handle design changes once the manufacturing wheels are already in motion. The second clip covers how Design for Manufacture relates to the actual cost of a production run. We hope there are more of these clips in the publishing pipeline so we’re keeping our eye on this channel.

The two videos are embedded below and at the time of writing had just a couple dozen views each and only one comment between the two of them. It seems sacrilege to say this, but we agree with that YouTube comment; these videos are gold.

Want to check out one of [Bunnie’s] latest projects? It’s a radio-based interactive badge.

Continue reading “[Bunnie Huang’s] Hardware Talks Top Your Watch List”

Oomlout’s guide to kitting


The team at oomlout has continued to post all the methods they use in their manufacturing process. This time around it’s the kitting process: how they actually packaged 30 identical SERB kits in an efficient fashion. We covered their wire cutting bot before, but they’ve got other dedicated machines like a sticker cutter. The stickers are used to remove all the cut acrylic pieces from the laser cutter as one unit. They’ve got some other tricks like using a scale to count bolt quantities, and an egg timer to keep track of the laser cutting. All of their envelopes are printed using a parallel port inkjet that has been modified to work with any thickness paper.

We love when hackers bother to post this much detail about their process. One of our favorites is [ladyada]’s full rundown of how the Minty Boost was created.

A history of SparkFun prototypes


If you haven’t checked out SparkFun Electronics’ prototype collection yet, you’re missing out. They unearthed many of their old prototypes and published them to show what kind of mistakes could be made. You’ll see plenty of errors and get hints on what to look for while developing your own hardware. This pairs well with their Design for Manufacture post. Along with the pile of broken board iterations, they also walk through how the company developed. Finally, they specifically cover the individual iterations of the BlueSMiRF.

One of the interesting modules in the gallery that never saw full release was the SparkFun Toys line pictured above. The individual units used the standoffs as the power and data bus. The four posts were arranged so they could only be connected in one orientation: power, ground, TX, and RX. It’s an interesting idea that seems like it might be worth exploring further. SparkFun says that it worked fine, but didn’t feel they had the resources to market it to the intended audience.