Homemade Gear Cutting Indexer Blends Art With Engineering

Ordinarily, when we need gears, we pop open a McMaster catalog or head to the KHK website. Some of the more adventurous may even laser cut or 3D print them. But what about machining them yourself?

[Uri Tuchman] set out to do just that. Of course, cutting your own gears isn’t any fun if you didn’t also build the machine that does the cutting, right? And let’s be honest, what’s the point of making the machine in the first place if it doesn’t double as a work of art?

[Uri’s] machine, made from brass and wood, is simple in its premise. It is placed adjacent to a gear cutter, a spinning tool that cuts the correct involute profile that constitutes a gear tooth. The gear-to-be is mounted in the center, atop a hole-filled plate called the dividing plate. The dividing plate can be rotated about its center and translated along linear stages, and a pin drops into each hole on the plate as it moves to index the location of each gear tooth and lock the machine for cutting.

The most impressive part [Uri’s] machine is that it was made almost entirely with hand tools. The most advanced piece of equipment he used in the build is a lathe, and even for those operations he hand-held the cutting tool. The result is an elegant mechanism as beautiful as it is functional — one that would look at home on a workbench in the late 19th century.

[Thanks BaldPower]

Continue reading “Homemade Gear Cutting Indexer Blends Art With Engineering”

Teaching An Old Lathe New Tricks With A Programmable Power Feed

Ask anybody whose spent time standing in front of a mill or lathe and they’ll tell you that some operations can get tedious. When you need to turn down a stainless rod by 1/4″ in 0.030″ increments, you get a lot of time to reflect on why you didn’t just buy the right size stock as you crank the wheel back and forth. That’s where the lead screw comes in — most lathes have a gear-driven lead screw that can be used to actuate the z-axis ( the one which travels parallel to the axis of rotation). It’s no CNC, but this type of gearing makes life easier and it’s been around for a long time.

[Tony Goacher] took this idea a few steps further when he created the Leadscrew Buddy. He coupled a beautiful 1949 Myford lathe with an Arduino, a stepper motor, and a handful of buttons to add some really useful capabilities to the antique machine. By decoupling the lead screw from the lathe’s gearbox and actuating it via a stepper motor, he achieved a much more granular variable feed speed.

If that’s not enough, [Tony] used a rotary encoder to display the cutting tool’s position on a home-built Digital Readout (DRO). The pièce de résistance is a “goto” command. Once [Tony] sets a home position, he can command the z-axis to travel to a set point at a given speed. Not only does this make turning easier, but it makes the process more repeatable and yields a smoother finish on the part.

These features may not seem so alien to those used to working with modern CNC lathes, but to the vast majority of us garage machinists, [Tony]’s implementation is an exciting look at how we can step up our turning game. It also fits nicely within the spectrum of lathe projects we’ve seen here at Hackaday- from the ultra low-tech to the ludicrously-precise.

Continue reading “Teaching An Old Lathe New Tricks With A Programmable Power Feed”

The King Of Machine Tools

The lathe is known as the King of Machine Tools for a reason. There are very few things that you can’t make with one. In fact, people love to utter the old saw that the lathe is the only machine tool that can make itself. While catchy, I think that’s a bit disingenuous. It’s more accurate to say that there are parts in all machine tools that (arguably) only a lathe can make. In that sense, the lathe is the most “fundamental” machine tool. Before you harbor dreams of self-replication, however, know that most of an early lathe would be made by hand scraping the required flat surfaces. So no, a lathe can’t make itself really, but a lathe and a skilled craftsperson with a hand-scraper sure can. In fact, if you’ve read the The Metal Lathe by David J. Gingery, you know that a lathe is instrumental in building itself while you’re still working on it.

We’re taking trip through the machining world with this series of articles. In the previous article we went over the history of machine tools. Let’s cut to the modern chase now and help some interested folks get into the world of hobby machining, shall we? As we saw last time, the first machine tools were lathes, and that’s also where you should start.

Continue reading “The King Of Machine Tools”

The Precision Upon Which Civilizations Are Built

If you’re interested in making things (particularly metal things), you’re on a road that eventually leads to machine tools. Machine tools have a special place in history, because they are basically the difference between subsistence farming and modern civilization. A bold statement, I realize — but the ability to make very precise things is what gave us the industrial revolution, and everything that snowballed afterward. If you want to build a modern life filled with jet airplanes and inexpensive chocolate, start here.

Precision is more than just a desirable property. It’s a product. It has value, there is competition to create it, and our ability to create it as a species has improved over time. When your “precision product” is in the centimeter range, congratulations — you can make catapults and portcullises. Once you get into the millimeter range, guess what? You can make fine millwork in fancy houses, and indoor plumbing. Once you get sub-millimeter, now things get really interesting. It’s time for steam engines and automobiles. Once you get into the micrometer range, well, now we’re talking artificial heart valves and spaceships. Much like materials science, the ability to create precision is the unsung foundation and driving force of our standard of living.

Okay, so assuming I’ve sold you on the value of this product called “precision”, how do we make it? Machine tools are how humans currently get there, despite the dreams of the 3D printer crowd. Yes, drizzled plastic is great and the future is bright, but for right now, subtractive manufacturing is where it’s at when something has to be perfect.

Continue reading “The Precision Upon Which Civilizations Are Built”