The Price Of Domestic Just In Time Manufacturing

Hardware is hard, manufacturing only happens in China, accurate pricing is a dark art. Facts which are Known To Be True. And all things which can be hard to conquer as an independent hardware company, especially if you want to subvert the tropes. You may have heard of [Spencer Wright] via his superb mailing list The Prepared, but he has also been selling an unusual FM radio as Centerline Labs for a few years. Two years ago they relaunched their product, and last year the price was bumped up by a third. Why? Well, the answer involves more than just a hand wave about tariffs.

The Public Radio is a single-station FM radio in a mason jar. It’s a seemingly simple single purpose hardware product. No big mechanical assemblies, no complex packaging, not even any tangential accessories to include. In some sense it’s an archetypically atomic hardware product. So what changed? A normal product is manufactured in bulk, tested and packaged, then stored in a warehouse ready to ship. But TPR is factory programmed to a specific radio station, so unless Centerline wanted one SKU for each possible radio station (there are 300) this doesn’t work. The solution was domestic (US) just in time manufacturing. When a customer hits the buy button, a unit is programmed, tested, packed, and shipped.

As with any business, there is a lot more to things than that! The post gives the reader a fascinating look at all the math related to Centerline Labs’ pricing and expenses; in other words, what makes the business tick (or not) including discussion of the pricing tradeoffs between manufacturing different components in Asia. I won’t spoil the logical path that led to the pricing change, go check out the post for more detail on every part. 

We love hearing about the cottage hardware world. Got any stories? Drop them in the comments!

Raspberry Preserve – A BitTorrent Sync Client In A Mason Jar

[Matt Reed] used a few off-the-shelf parts and built a Raspberry-Pi based BitTorrent Sync client to help backup files. What makes it stand out is the idea of using a Mason Jar as the enclosure and the nice build finish. Mason Jars have long been used to preserve food. [Matt] wanted to use the Mason Jar to help preserve family memories.

Basically, he just stuffed a Raspberry Pi inside a jar with some LED’s and put BitTorrent Sync on it. He started off with a nice, square piece of wood and mounted the lid on it. Holes were drilled to fix the four LED’s and faux crystal drawer pull knobs. The Pi was connected to power and Ethernet and the LED’s wired up. The software is quite straightforward – just install BitTorrent Sync on the Raspberry Pi. He wrote a Node.js script to constantly check if BitTorrent Sync is transferring any data, and if it is, blink the LED’s so it looks cool. If no data is being transferred, the LED’s just glow solid red. Once it is plugged into power and connected to the internet, any photo or video (or any file for that matter) that is put inside a special folder called “Preserve” on any of his devices, gets sync’ed and copied to the “Raspberry Preserve” – preserved for posterity.

Laminated Wooden Case Brings A Dropped Coffee Grinder Back From The Junk Heap


Instead of giving it up for dead, [Suprise Pink Mist] fabricated a replacement case for the motor and blade of his broken coffee grinder. The original enclosure was made of plastic, which didn’t survive being dropped. There isn’t an image of what those plastic parts looked like, but we have to think they were nowhere near as neat as the replacement.

The first step was to cut a set of plywood discs to the approximate outside dimensions. Since the base of the motor has several different diameters each disc had a void cut out of its center to match. The image to the right shows the motor sitting upside down next to the stacked plywood. The black electrical tape seals around the mason jar ring which was a perfect friction fit with the original bowl of the grinder. Once everything was glued together the outside edges were flattened on a belt sander and the mason jar was screwed in place to house the beans during grinding.

[via Reddit]

Firefly Cap Has No Battery And Is Meant For Indoor Light Harvesting

[Michael Ossman] wrote in to show off his newest project. He calls it the Firefly cap, which we think is something of a play on words. You can see that it serves as the cap of a Mason jar, but it also uses a supercap instead of a rechargeable battery.

Posts about firelfly jars go way back. And [Michael] mentions that a similar firefly project was his first embedded project. The concept uses LEDs suspended in a jar. When a light detector senses the target level of darkness, the lights inside begin to twinkle like their insect namesakes.

We like this design for two reasons. It’s aimed at collecting light in an indoor environment so you don’t have to worry about placing it in the sun. And it uses a super capacitor instead of a battery so this should truly keep going and going without wearing out the energy storage components. We also like the fact that although this is a Kickstarter project, everything you need to build your own is already available at the Github repository.

DIY Vaporizer

Here’s a DIY vaporizer build. It uses a 30 watt Radio Shack soldering iron as a heat source that is regulated with a common dimmer switch. This is done by removing the soldering tip and replacing it with threaded rod attached to a brass pipe fitting assembly. This is housed inside of a Mason jar with a copper pipe for air intake and another for output. Not surprisingly the creator tipped us off anonymously, saying that this a “smoking accessory”. A bit of searching and we came across this Wikipedia article about a Volcano Vaporizer which sheds light on what one is used for.

We don’t condone using illicit substances. But even more so, we’re skeptical about breathing through this thing because of the warning that [Anon] included about noxious vapors put off by the epoxy putty when it heats up. Still, it’s an interesting build so we though we’d share.