Lathe’s Tool Holder Holds A Rotary Tool

January 20, 2019 by 20 Comments

What is better than a tool? Two. What is better than two? Two tools tooling together. [tintek33] wanted a rotary tool to become an attachment on his mini lathe, the video is also below the break. Fortunately, Dremels and Proxxons are built to receive accessories, or in this case, become one. Even if the exact measurements do not apply to your specific hardware, we get to see the meat of the procedure from concept to use.

We start with where the rotary tool should be and get an idea of what type of bracket will be necessary. The design phase examines the important dimensions with a sketch and then a CAD mock-up. Suitably thick material is selected, and the steps for pulling the tool from the raw stock are shown with enough detail to replicate everything yet there is no wasted time in this video. That is important if you are making a quick decision as to whether or not this is worth your hard work. Once the brace is fully functional and tested, it is anodized for the “summer ocean” blue color to make it easy to spot in the tool heap. Some complex cuts are made and shown close-up.

Thank you [jafinch78] for your comment on Take a Mini Lathe for a Spin and check out [tintek33] using his mini lathe to make a hydraulic cylinder for an RC snow plow.

Continue reading “Lathe’s Tool Holder Holds A Rotary Tool” →

Radio Telescopes Horn In With GNU Radio

January 20, 2019 by 26 Comments

Who doesn’t like to look up at the night sky? But if you are into radio, there’s a whole different way to look using radio telescopes. [John Makous] spoke at the GNU Radio Conference about how he’s worked to make a radio telescope (PDF) that is practical for even younger students to build and operate.

The only real high tech part of this build is the low noise amplifier (LNA) and the project is in reach of a typical teacher who might not be an expert on electronics. It uses things like paint thinner cans and lumber. [John] also built some blocks in GNU Radio that made it easy for other teachers to process the data from a telescope. As he put it, “This is the kind of nerdy stuff I like to do.” We can relate.

The telescope is made to pick up the 21 cm band to detect neutral hydrogen from the Milky Way. It can map the hydrogen in the galaxy and also measure the rotational speed of the galaxy using Doppler shift. Not bad for an upcycled paint thinner can. These are cheap enough, you can even build a fleet of them.

This would be a great project for anyone interested in radio telescopes or space. However, it is particularly set up for classroom use. Students can flex their skills in math, engineering, programming, and — of course — astronomy and physics.

Continue reading “Radio Telescopes Horn In With GNU Radio” →

CNC Mill Repairs IPhone 7

January 20, 2019 by 39 Comments

Modern smartphones are highly integrated devices, bringing immense computing power into the palm of one’s hand. This portable computing power and connectivity has both changed society in innumerable ways, and also tends to lead to said powerful computers ending up dropped on the ground or into toilets. Repairs are often limited to screen replacement or exchanging broken modules, but it’s possible to go much further.

The phone is an iPhone 7, which a service center reported had issues with the CPU, and the only fix was a full mainboard replacement. [The Kardi Lab] weren’t fussed, however, and got to work. The mainboard is installed in a CNC fixture, and the A10 CPU is delicately milled away, layer by layer. A scalpel and hot air gun are then used for some further cleanup of the solder pads. Some conductivity testing to various pads is then carried out, for reasons that aren’t entirely clear.

At this point, a spare A10 CPU is sourced, and a stencil is used to apply solder paste or balls – it is not immediately obvious which. The new chip is then reflowed on to the mainboard, and the phone reassembled. The device is then powered on and shown to be functional.

It’s an impressive repair, and shows that modern electronics isn’t so impossible to fix – as long as you have the right tools to hand. The smart thing is, by using the CNC machine with a pre-baked program, it greatly reduces the labor required in the removal stage, making the repair much more cost-effective. The team are particularly helpful, linking to the tools used to pull off the repair in the video description. We’ve seen similar hacks, too – such as upgrading an iPhone’s memory.  Video after the break.

[Thanks to Nikolai for the tip!]

Continue reading “CNC Mill Repairs IPhone 7” →

Cloning Knobs For Vintage Testing Equipment

January 20, 2019 by 12 Comments

Knobs! Shiny candy-colored knobs! The last stand of skeuomorphism is smart light switches! Everyone loves knobs, but when you’re dealing with vintage equipment with a missing knob, the odds of replacing it are slim to none. That’s what happened to [Wesley Treat] when he picked up a vintage Philco tube tester. The tester looked great, but a single knob for a rotary switch was missing. What to do? Clone some knobs! You only need some resin and a little bit of silicone.

The process of copying little bits of plastic or bakelite is fairly standard and well-tread territory. Go to Michaels or Hobby Lobby, grab some silicone and resin, make a box, put your parts down, cover them in silicone, remove the parts, then put resin in. For simple parts, and parts with flat bottoms like knobs, this works great. However, there’s something weird about the knob on this old Philco tube tester. Firstly, it doesn’t fit a standard 1/4″ shaft — it’s a bit bigger. There’s also no set screw. Instead, this knob has a stamped spring aligning it with the flat part of the D-shaft in this rotary switch. This means a copy of this knob wouldn’t be useful to anyone else, and that no other knob would work with this tube tester.

However, a bit of clever engineering would make a copy of this knob fit the existing switch. Once the resin was cured, [Wesley] drilled out the hole, then sanded a dowel down to fit into the flat of the D-shaft. It took a little kergiggering, but the knob eventually fit onto one of the rotary switches. Not bad for a few bucks in silicone and resin.

You can check out the entire build process below.

Continue reading “Cloning Knobs For Vintage Testing Equipment” →

Epsom Salts Restores Lead Acid Battery

January 20, 2019 by 21 Comments

Despite a lot of advances in battery technology, lead acid batteries are still used in many applications due to cost and their ability to provide a lot of surge current. But they don’t last forever. However, [AvE] shows that in some cases a failed battery can be restored with — of all things — epsom salts. If it makes you feel funny to use the stuff grandpa soaks in when he has a backache, you can call it magnesium sulfate.

You can find a complete explanation in the video below (which includes [AvE’s] very colorful language), but fundamentally, the magnesium sulfate dissolves lead sulfate build-up on the battery plates. The fix is usually temporary because this build-up occurs with other failure mechanisms like plate material shedding and collecting at the bottom of the battery. Obviously, epsom salt can’t repair damaged plates or do any other magic cure.

Continue reading “Epsom Salts Restores Lead Acid Battery” →

Strobe For Wood Turning Makes Inspection Easy

January 19, 2019 by 44 Comments

The lathe is a simple enough tool to understand, but requires much practice to truly master. During the turning process, it’s often necessary to inspect the workpiece. This generally necessitates stopping the lathe, waiting for everything to spin down, and then starting again. This can be a major time sink when added up across the full scope of a project. However, the magic of strobes can help.

The basics of [Darcy]’s project will be familiar to any hacker who has worked with rotating machinery before. The rotational speed of the lathe is measured, in this case using a reed switch and a magnet. This signal is fed to a microcontroller, which controls the strobing of an LED lamp. By synchronizing the flashes to the speed of the lathe, it’s possible to view the workpiece as if it were standing still. By adjusting the offset of the flashes to the position of the lathe, it’s also possible to rotate this view to see the entire workpiece – all while the lathe remains spinning.

Further photos and videos are available in the Reddit thread. [Darcy] reports that despite his best efforts, he couldn’t quite find a business case for producing the hardware commercially, but the idea was too useful to leave languishing in a notebook. We’d love to hear your ideas on how this could improve turning projects, so be sure to let us know in the comments. If you’re just getting started with turning, it might be worth cutting a test bar to make sure your rig is up to snuff.

Always Have A Square To Spare

January 19, 2019 by 24 Comments

Some aspects of humanity affect all of us at some point in our lives. Whether it’s getting caught in the rain without an umbrella, getting a flat tire on the way to work, or upgrading a Linux package which somehow breaks the entire installation, some experiences are truly universal. Among these is pulling a few squares of toilet paper off the roll, only to have the entire roll unravel with an overly aggressive pull. It’s possible to employ a little technology so that none of us have to go through this hassle again, though.

[William Holden] and [Eric Strebel] have decided to tackle this problem with an innovative bearing of sorts that replaces a typical toilet paper holder. Embedded in the mechanism is a set of magnetic discs which provide a higher resistance than a normal roll holder would. Slowly pulling out squares of paper is possible, but like a non-Newtonian fluid becomes solid when a higher force is applied, the magnets will provide enough resistance when a higher speed tug is performed on the toilet paper. This causes the paper to tear rather than unspool the whole roll, and also allows the user to operate the toilet paper one-handed.

This is a great solution to a problem we’ve all faced but probably forgot about a minute after we experienced it. And, it also holds your cell phone to keep it from falling in the toilet! If you’d like to check out their Kickstarter, they are trying to raise money to bring the product to market. And, if you want to upgrade your toilet paper dispenser even further, there’s also an IoT device for it as well, of course.

Continue reading “Always Have A Square To Spare” →