While it might be tempting to start soldering a circuit together once the design looks good on paper, experience tells us that it’s still good to test it out on a breadboard first to make sure everything works properly. That might be where the process ends for one-off projects, but for large production runs you’re going to need to test all the PCBs after they’re built, too. While you would use a breadboard for prototyping, the platform you’re going to need for quality control is called a “bed of nails“.
This project comes to us by way of [Thom] who has been doing a large production run of circuits meant to drive nixie tubes. After the each board is completed, they are laid on top of a number of pins arranged to mate to various points on the PCB. Without needing to use alligator clamps or anything else labor-intensive to test, this simple jig with all the test points built-in means that each board can be laid on the bed and tested to ensure it works properly. The test bed looks like a bed of nails as well, hence the name.
There are other ways of testing PCBs after production, too, but if your board doesn’t involve any type of processing they might be hard to implement. Nixie tubes are mostly in the “analog” realm so this test setup works well for [Thom]’s needs.
We all maintain this balancing act between the cool things we want, the money we can spend, and our free time. When the pièce de résistance is a couple of orders of magnitude out of our budget, the only question is, “Do I want to spend the time to build my own?” [Nick Charlton] clearly answered “Yes,” and documented the process for his Nautilus speakers. The speaker design was inspired by Bowers & Wilkins and revised from a previous Thingiverse model which is credited.
The sound or acoustic modeling is not what we want to focus on since the original looks like something out of a sci-fi parody. We want to talk about the smart finishing touches that transform a couple of 3D printed shells into enviable centerpieces. The first, and most apparent is the surface. 3D prints from consumer FDM printers are prone to layer lines, and that aesthetic has ceased to be trendy. Textured paint will cover them nicely and requires minimal elbow grease. Besides sand and shells go together naturally. At first glance, the tripod legs holding these speakers seemed like a classy purchase from an upscale furniture store, but they are, in fact, stained wood and ground-down bolts. Nicely done.
A lot of people make the argument that you can’t go wrong buying a tool made in USA, Germany, Japan, Switzerland, etc. They swear that any Chinese tool will be garbage and it’s not worth purchasing them. Now, any discerning mind will say, “Wait a minute, why? China has a huge economy, experienced people, and the ability to use all the scary chemicals that make the best steel. Why would their tools be any better or worse than ours?” It’s a very valid argument. There are lots of Chinese tools that are the best in the world. Most of what we see in our stores are not. So what is the difference. Why does a country who can make the best tools not make the best tools? Surely it isn’t purely cost cutting. Is it cultural? The opinion I wish to put forth is that it’s a matter of design intent communication.
I’ve worked as an engineer in industry. The one common thread between a quality product and a bad product has always been this, ”Is the person who designed the product involved in making the product?” If the person or peoples who imbued the design intent into the original product are actively involved in and working towards the execution of that product, that product has a vastly greater chance of being good. Or in other words: outsourcing doesn’t produce a bad product because the new people making the product don’t care. It makes a bad product because the people who understand the intent behind the product are separated from its execution.
Let’s take the Crescent wrench as an example. Crescent wrenches used to be made in USA. In the past few years they have begun to make them in China. We can spot many visual differences right away. The new Crescent wrench has a different shape, the logo has changed and the stamping for the logo is dodgy, and worse, the tool just doesn’t operate as well as it used to. The jaws aren’t as hard and they wiggle more. What happened? How could Crescent mess up their flagship so badly. Surely they intended just to cut costs, not to reduce quality. This isn’t shameful in itself
What happened to the Crescent wrench is easily explained by anyone who has seen a product from design to execution before. A factory in the USA set out to make a good adjustable wrench. Hundreds of engineers and employees worked in a building to make a good wrench. When their machines didn’t work, they came up with solutions. When their quality was lacking, they implemented better processes. They had a list of trusted suppliers. They could guarantee that the materials that came in would be imbued with their vision and intent when the product came out. The intent and will of all those people built up in one place over time.
Do you think it’s not really possible to get amazing resolution from extruder-based 3D printers? You’re wrong, and this post about the attainable quality of prints on the Ultimaker proves it. The Yoda bust seen above was printed with a layer thickness of 0.02mm. This is a hack in itself because this process actually used two different layer thicknesses. The interior of the print, which you can’t see, but serves as a support mechanism for the object was printed at 0.04mm, with just the visible perimeter printed in the smaller thickness. That trickery is just fine with us if this is the result.
[Dave Durrant] discusses the press the Ultimaker has received, which mostly focused on the relatively fast printing process this hardware uses. But he didn’t think the story of the quality you can get with the device was being told. So he put out a call on the mailing list to send in pictures of high-quality 3D prints and he wasn’t disappointed by the response. You’ll see images of busts, bodies, gears, animals, and art pieces. There’s information about how they were printed, but even those not interested in the particulars will appreciate the macro photography that gives you an up-close look at how far we’ve come with these table-top rapid prototyping machines.
[The Moogle] just got his new Arduino Uno; wow, that was fast. What should have been a happy unboxing turned sour when he took a close look at the board. It seems that it exhibits several examples of sloppy fabrication. The the lower-left image shows unclean board routing, a discolored edge, and a sharp tooth sticking out from the corner. The shield header shown in the upper left is not flush with the board, resulting in a weaker physical union and a crooked connection. There are vias that look like they’re not be centered in the solder mask, and areas where raw copper is exposed.
It saddens us to see this because the original Arduino boards were so well manufactured. Keep in mind that this may be an isolated case, and as of yet the company hasn’t been given the chance to swap out the board for one that has passed a more rigorous quality control inspection. But if you’ve already ordered one of your own, take a close look and make sure you’re satisfied with it upon arrival.
Update #2: [Massimo Banzi], one of the founders of Arduino, took the time to comment on this post. It details the organization’s willingness to remedy situations like [The Moogle] encountered and also links to the recent Arduino blog post.
Take our reader survey. Do it. Do it right now. Do you think we should run more articles on the dietary needs of Llamas? Here is your chance to let us know. We got a lot of great feedback from [Jason]’s post, and now we’re ready for more. We’ve put together 10 quick questions that will help us get a feeling for what you want. We will be choosing 5 participants at random to give free t-shirts (the basic logo one).
Update: While we wait for our survey slave to get the changes made, please just put something in the fields that are mandatory(questions 7-9). Even if you put “no opinion”, we’ll get good info from the rest of the survey.