An Open-Source Turbomolecular Pump Controller

It’s not every project write-up that opens with a sentence like “I had this TURBOVAC 50 turbomolecular pump laying around…”, but then again not every write-up comes from someone with a lab as stuffed full of goodies as that of [Niklas Fauth]. His pump had an expired controller board, so he’s created an open-source controller of his own centred upon an STM32. Intriguingly he mentions its potential use as “I want to do more stuff with sputtering and Ion implantation in the future“, as one does of course.

So given that probably not many Hackaday readers have a turbomolecular pump lying around but quite a few of you will find the subject interesting, what does this project do? Sadly it’s a little more mundane than the pump itself, since a turbomolecular pump is a highly specialised multi-stage turbine, this is a 3-phase motor controller with analogue speed feedback taken from the voltage across a couple of the motor phases. For this reason he makes the point that it’s a fork of his hoverboard motor controller software, the fruits of which we’ve shown you in the past. There isn’t a cut-out timer should the motor not reach full speed in a safe time, but he provides advice as to where to look in the code should that be necessary.

This is by no means the first turbomolecular pump to make it to these pages, in 2016 we brought you one taking inspiration from a Tesla turbine.

The Fab Lab Next Door: DIY Semiconductors

You think you’ve got it going on because you can wire up some eBay modules and make some LEDs blink, or because you designed your own PCB, or maybe even because you’re an RF wizard. Then you see that someone is fabricating semiconductors at home, and you realize there’s always another mountain to climb.

We were mesmerized when we first saw [Sam Zeloof]’s awesome garage-turned-semiconductor fab lab. He says he’s only been acquiring equipment since October of 2016, but in that short time he’s built quite an impressive array of gear; a spin-coating centrifuge, furnaces, tons of lab supplies and toxic chemicals, a turbomolecular vacuum pump, and a vacuum chamber that looks like something from a CERN lab.

[Sam]’s goal is to get set up for thin-film deposition so he can make integrated circuits, but with what he has on hand he’s managed to build a few diodes, some photovoltaic cells, and a couple of MOSFETs. He’s not growing silicon crystals and making his own wafers — yet — but relies on eBay to supply his wafers. The video below is a longish intro to [Sam]’s methods, and his YouTube channel has a video tour of his fab and a few videos on making specific devices.

[Sam] credits [Jeri Ellsworth]’s DIY semiconductor efforts, which we’ve covered before, as inspiration for his fab, and we’re going to be watching to see where he takes it from here. For now, though, we’d better boost the aspiration level of our future projects.

Continue reading “The Fab Lab Next Door: DIY Semiconductors”

Everyman’s Turbomolecular Pump

What can you do with a very good vacuum pump? You can build an electron microscope, x-ray tubes, particle accelerators, thin films, and it can keep your coffee warm. Of course getting your hands on a good vacuum pump involves expert-level scrounging or a lot of money, leading [DeepSOIC] and [Keegan] to a great entry for this year’s Hackaday Prize. It’s the Everyman’s Turbomolecular Pump, a pump based on one of [Nikola Tesla]’s patents. It sucks, and that’s a good thing.

The usual way of sucking the atmosphere out of electron microscopes and vacuum tubes begins with a piston or diaphragm pump. This gets most of the atmosphere out, but there’s still a little bit left. To get the pressure down even lower, an oil diffusion pump (messy, but somewhat cheap) or a turbomolecular pump (clean, awesome, and expensive) is used to suck the last few molecules of atmosphere out.

The turbomolecular pump [DeepSOIC] and [Keegan] are building use multiple spinning discs just like [Tesla]’s 1909 patent. The problem, it seems, is finding a material that can be made into a disc and can survive tens of thousand of rotations per minute. It’s a very, very difficult build, and a mistake in fabricating any of the parts will result in a spectacular rapid disassembly of this turbomolecular pump. The reward, though, would be great. A cheap turbomolecular pump would be a very useful device in any hackerspace, fab lab, or workshop garage.

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Hacklet 100 – The 2016 Hackaday Prize

Welcome to the 100th Hacklet! This has been a huge week for Hackaday, as we launched The 2016 Hackaday Prize. We’ve invited you to change the world. Hackers, makers, and engineers have already answered the call, with nearly 200 entered projects! What better way to celebrate our 100th Hacklet than taking a look at a few of these early entrants?

rarmWe start with [Patrick Joyce] and Raimi’s Arm – Bionic Arm for Kids. Raimi was born with an arm which ends just below the elbow. She’s still a kid – and growing, which means she will quickly grow out of any prosthetic. This has placed bionic arms out of her reach. [Patrick] saw a plea from Raimi’s father for help. 3D printed arms for the disabled are a thing, but [Patrick] couldn’t find one which fit the bill for Raimi. So he’s set out to design one himself. This will be an open source project which anyone with the proper tools can replicate. [Patrick] has already created several test rigs, and is well on the way to building an arm for Raimi and others!

latheNext up is [castvee8] who has entered the 2016 Hackaday Prize with Building Simplified Machinery. Over the years, [Castvee8] has built a few 3D printers and CNC machines. These projects always start with buying the same parts over and over: ground rods, linear bearings, stepper motors, drivers, etc. [Castvee8] is trying to build 3D printed machines which use as few of these vitamins as possible, yet are still strong enough to work in wood, plastic, wax, foam, and other light maker-friendly materials. So far the simple, modular components and electronics have led to a mini mill, mini lathe, and a drill press for things like printed circuit boards. Keeping things low-cost will make these tools accessible to everyone.

turpump[Keegan Reilly] entered Everyman’s turbomolecular pump. Vacuum pumps are great, but everyone knows the real fun starts around 10^-7 Torr. Pulling things down this low requires a specialized pump. Two common designs are oil diffusion pumps and Turbomolecular pumps. Oil diffusion is cheap, but not everyone wants a hot vat of oil bubbling away in their vacuum chamber. Turbomolecular pumps are much cleaner, but very expensive. [Keegan] is attempting to design a low-cost version of a turbomolecular pump. He’s trying to use Tesla’s bladeless turbine design rather than the traditional bladed turbines used in commercial pumps. So far tests using a Dremel tool and paper discs have been promising – nothing has exploded yet!

commongroundFinally, we have [Samuel Bowman] with Seamless IoT Protocol Translation: Common Ground. Love it or hate it, the Internet of Things is going to be here for a while. Every device seems to speak a different language though . Z-wave, Zigbee, LoRa, WiFi, and a host of other protocols, all on different frequencies. Some are frequency hopping, some use mesh networks. [Samuel] is trying to design one device to translate between any of the emerging standards. Common Ground started as a science fair project connecting MQTT to Phillips Hue devices. Once [Samuel] achieved that goal, he realized how much potential there is in a universal translator box. We’re hoping [Samuel] achieves his goals quickly – it seems like new IoT standards are being introduced every day.

New projects are entering the 2016 Hackaday Prize every hour! You can see the full list right here. That’s it for the 100th Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!