Casting Turbines For A World Speed Record Motorcycle

November 8, 2015 by Brian Benchoff 24 Comments

[Anders] is going to beat the land speed record for a turbine-powered motorcycle. It’s a project he’s been working on for years now, and just this week, he put the finishing touches on the latest part of the build. He successfully cast the compressor for a gas turbine engine that’s twice as powerful as the one he has now.

This compressor piece was first 3D printed, and this print was used as a positive for a sand – or more specifically petrobond – mold. The material used in the casting is aluminum, fluxed and degassed, and with a relatively simple process, [Anders] came away with a very nice looking cast that only needs a little bit of milling, lathing, and welding to complete the part.

In the interests of accuracy, and just to make sure there’s no confusion, this ‘jet’ engine is actually a gas turbine, of which there are many configurations and uses. The proper nomenclature for this engine is a ‘turboshaft’ because the power is directed to a shaft which drives something else. This is not a new build; we’ve been covering [Anders]’ build for the better part of two years now, and although [Anders] intends to break the world record at the Bonneville salt flats eventually, he won’t be beating the ultimate land speed record – that title goes to a car – and he won’t be beating the speed record for all motorcycles. Instead, [Anders] plans to break the record for experimental propulsion motorcycles, or motorcycles powered by electric motors, steam, jet engines, or in this case, ‘turboshafts’.

It should also be noted that [Anders] frequently does not wear hearing or eye protection when testing his gas turbine engine. That is an exceedingly bad idea, and something that should not be attempted by anyone.

As an additional note for safety, in the video below of [Anders] pouring aluminum into his mold, the ground looks wet. This is terrifically dangerous, and steam explosions can kill and maim even innocent bystanders. This is not something that should be attempted by anyone, but we do thank [Anders] for sharing his project with us.

Continue reading “Casting Turbines For A World Speed Record Motorcycle” →

Slide Rules Were The Original Personal Computers

November 5, 2015 by Al Williams 67 Comments

Unless you are above a certain age, the only time you may have seen a slide rule (or a slip stick, as we sometimes called them) is in the movies. You might have missed it, but slide rules show up in Titanic, This Island Earth, and Apollo 13. If you are a fan of the original Star Trek, Mr. Spock was seen using Jeppesen CSG-1 and B-1 slide rules in several episodes. But there was a time that it was common to see an engineer with a stick hanging from his belt, instead of a calculator or a cell phone. A Pickett brand slide rule flew to the moon with the astronauts and a K&E made the atomic bomb possible.

Slide rules are a neat piece of math and history. They aren’t prone to destruction by EMP in the upcoming apocalypse (which may or may not include zombies). Like a lot of things in life, when it comes to slide rules bigger is definitely better, but before I tell you about the 5 foot slide rule in my collection, let’s talk about slide rules in general.
Continue reading “Slide Rules Were The Original Personal Computers” →

Programmable Logic: Build Yourself A CPLD Module

October 28, 2015 by Bil Herd 80 Comments

A Complex Programmable Logic Device (CPLD) is a great piece of hardware to have in your repertoire. As its name implies, you can program these chips to serve the logic functions you need. This might be replacing an obsolete chip, or maybe just a way to learn and try different techniques. What better way to learn than to get your hands on a CPLD and give it a try?

I created a CPLD module with the intent of being able to plug it into lots of things including solderless breadboards, but I screwed up. It seems that the plugin space available on a solderless breadboard is 1.1”, I had made the footprint 1” wide leaving no room for a row of wires on both sides. Duh.

But let me back up and show more about what I’m doing , I wanted to make a programmable piece of logic that could be built as a kit one could easily solder at home, could be programmed in-circuit, and could work at 3.3 or 5 volts.

To implement an easily solderable kit I went with an older CPLD part that also has 3.3v and 5v versions that will maintain its programming regardless of power. The logic itself is a CPLD IC from the Altera Max family with two versions that fit the board with either 32 or 64 macrocells. A macrocell is the basic logic building block and it is programmed with logic “terms” and then interconnected to other macrocells through a programmable interconnect.

Continue reading “Programmable Logic: Build Yourself A CPLD Module” →

El Cheapo Electric Screwdriver

October 26, 2015 by Anool Mahidharia 28 Comments

If you have a few hobby servos lying around, here’s a hack that let’s you recycle them and put them to good use. [Kedar Nimbalkar] took a micro servo and converted it into an electric screwdriver. It is simple enough to deserve a short video showing how he did it.

He starts by opening up a 9G micro servo and removing the electronics. All that’s needed is the DC motor and the gears. The two motor wires go directly to the battery via a polarity reversal switch to allow the motor to turn in both directions. The servo horn is cut to size so that it is a tight fit inside the screwdriver socket. A liberal amount of glue is used to make sure it stays in place. The horn is then attached to the modified servo, ready to take interchangeable bits. One last mod before closing up the servo is to convert it to continuous rotation by cutting off the stopper in the drive gear.

He built the power supply from scratch, using a 18650 Li-Po battery, a 5V USB charger, a DPDT switch to allow direction control and a push button to actuate the screw driver. A pair of LED’s connected back to back serve as direction indicators as well as some local illumination.

There’s lot’s of scope to improvise and do everything differently, but the basic premise of using unused servos for a handy electric screwdriver is pretty neat.

Continue reading “El Cheapo Electric Screwdriver” →

DIY Powder Coating

October 25, 2015 by Brian Benchoff 65 Comments

If you don’t yet have a toaster oven you can’t use with food, here’s yet another reason: DIY powder coating. Powder coating is much harder and more durable than paint – a property imbued to it by the fact that it’s baked on to a part. [Thomas] had a go at powder coating some skateboard trucks, and with the right tools, found the process downright easy.

[Thomas] only needed a few things to powder coat his parts, the first and most important being a powder coat gun. A few years ago, Craftsman produced a powder coat gun that’s still available on Amazon and eBay for about $50. Powders are plentiful and cheap in small quantities. The only other tools needed were an N95 or better respirator, some high temperature tape for masking off the part and a toaster oven. If you want to coat big parts, there are DIY oven options for that.

After the part was sandblasted down to bare metal, [Thomas] masked off all the holes and threads of the part with polyimide tape. Any tape that’s capable of withstanding high temperatures will do, and most of us have a roll of Kapton sitting next to a 3D printer, anyway.

The part is coated with powder via an electrostatic charge, and this means attaching a ground lead from the gun to the part. After that, it’s just filling the gun with powder, putting it in the oven set at 450°F, and letting the powder liquefy.

In the video below, you can see [Thomas] sandblasting, powdering, and baking a set of aluminum skateboard trucks using his method. Compared to other methods of finishing metal parts – anodizing or plating, for instance, powder coating is remarkably easy and something anyone can do in a garage.

Thanks [Tyler] for sending this one in.

Continue reading “DIY Powder Coating” →

A Small, 1000W Induction Heater

October 23, 2015 by Brian Benchoff 100 Comments

[Proto G] built a small, desktop induction heater that is capable of making small castings, melting small amounts of metal, and functioning as one of the best solder pots we’ve ever seen.

The induction heater is built from a custom Zero Voltage Switching (ZVS) driver and powered by a small 48V, 1000W power supply. While this makes for an exceptionally small induction heater, it’s still very capable. In the video below, it only takes a few seconds to heat a screwdriver up to a temperature that will melt solder.

While an induction heating machine is essentially useless for irons unless you have a few antique, unpowered, blowtorch-powered soldering irons, it does make for a great solder pot. [Proto G] replaced the working coil in his induction heater with litz wire. The actual solder pot is made out of steel conduit wrapped with aerogel-infused fiberglass insulation. Compared to his old solder pot, this machine heats up instantly, and is more than capable of wetting a few wire connections.

The future plan for this inductive heater is to make a few more attachments for different metals, and a [Proto G] has a few aerogel blankets he could use to make some small metal castings.

Continue reading “A Small, 1000W Induction Heater” →

Upgrading Rigol’s More Expensive Oscilloscopes

October 22, 2015 by Brian Benchoff 27 Comments

[mosaicmerc] over on hackaday.io has upgraded his Rigol DS2072A oscilloscope to a DS2302A, turning an $800 oscilloscope into one that sells for $2500, with all the bandwidth, storage depth, and options of the more expensive model.

Rigol o-scopes have a long and storied history of unlocking, hacking, and upgrading. The original hack that put Rigol on the map was the DS1052E upgrade that turned a 50MHz scope into a 100MHz scope. The latest low-end Rigol scope, the 1054Z can be unlocked in software to become an 1104Z with 100MHz of bandwidth, SPI, I2C, and RS232 decoders, twice the storage depth, and more triggers. It appears Rigol’s engineers are designing their products to capitalize on the hacker’s proclivity to buy their tools to get the ‘free’ upgrade. This, of course, sounds just slightly insane, but no one seems to mind.

The process of upgrading the Rigol DS2072A scope is documented over on the EEVBlog, and requires only a USB cable and a computer with the Labview Runtime Engine installed. It’s literally as simple as pressing a few buttons; a far cry from the previous keygen method that was also engineered over on the EEVBlog.