Take A Mini Lathe For A Spin

December 31, 2018 by 24 Comments

[This Old Tony] is no stranger to quality tools, but he started on a mini lathe. Nostalgia does not stop him from broadcasting his usual brand of snark (actually, it is doubtful that anything short of YouTube going offline will stop that). He rates the lathe’s ability to machine different materials and lets you decide if this is an investment, or a money pit.

Lathe parts range from a chintzy start/stop button assembly that looks like it would be at home on a Power Wheels restoration project to a convenient cam locking mechanism on the tail stock which is an improvement on the lathe with which our narrator learned. We see the speed tested and promptly disproved as marketing hoopla unless you allow for a 40% margin of error. It uses a 500 watt DC motor, so don’t try correcting for mains power frequency differences. The verdict on the lead screw and thread dial is that you get what you pay for and this is demonstrated by painstakingly cutting threads into aluminum. Finally, we see torture tests on cold rolled steel.

Maybe someone from the mini lathe community will stop by with their two-cents. If you appreciate this introduction to lathes, consider [This Old Tony]’s guide to CNC machines or injection molding. But for us, [Quinn Dunki’s] series of machine tools has been a real treat this year.

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Hackaday guide to Lathes

Lathe Headstock Alignment: Cutting A Test Bar

August 7, 2018 by 39 Comments

Let’s say you’ve recently bought a lathe and set it up in your shop. Maybe you’ve even gone and leveled it like a boss. You’re ready to make chips, right? Well, not so fast. As real machinists will tell you, you can use all the levels and lasers and whatever that you want, but the proof is in the cut. Precision leveling gets your machine in the ballpark (machinists have very small ballparks) but the final step to getting a machine to truly perform well is to cut a test bar. This is a surefire way to eliminate any last traces of twist in the bed.

There are two types of test bars. One is for checking headstock-to-ways alignment, which is what we’re doing here. There’s another type used for checking tailstock alignment, but that’s a subject for another day.

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Hackaday guide to Lathes

The Machinists’ Mantra: Level Thy Lathe

July 10, 2018 by 69 Comments

Let’s say you’ve gone and bought yourself a sweet sweet metal lathe. Maybe it’s one of the new price-conscious Asian models, or maybe it’s a lovely old cast iron beast that you found behind a foreclosed machine shop. You followed all the advice for setting it up, and now you’re ready to make chips, right? Well, not so fast. Unlike other big power tools, such as band saws or whatever people use to modify dead trees, machine tools need to be properly level. Not, “Hurr hurr my carpenter’s level says the bubble is in the middle”, but like really level.

This is especially true for lathes, but leveling is actually a proxy for something else. What you’re really doing is getting the entire machine in one plane. Leveling is a primitive way of removing twist from the structure. It may not seem like a huge piece of cast iron could possibly twist, but at very small scales it does! Everything is a spring, and imperceptible twist in the machine will show up as your lathe turning a couple thousandths of taper (cone) when it should be making perfect cylinders. All this is to say, before making chips, level your lathe. Let me show you the way. Continue reading “The Machinists’ Mantra: Level Thy Lathe” →

Hackaday guide to Lathes

Preparing For A Lathe: How To Move 3000 Pounds Of Iron

June 4, 2018 by 91 Comments

You say to yourself, “Self, I want, nay, need a lathe”. Being a good little trooper, you then did all your research, having chosen Import or American, Imperial or Metric, and all your feed options and such. You then pulled the trigger and the machine is en route to your shop. Now what?

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Hackaday guide to Lathes

A Buyer’s Guide To Lathe Options

April 24, 2018 by 59 Comments

Lathes are complicated machines, and buying one requires weighing a lot of options. We’ve already talked about buying new Asian, or old American machines (with apologies to the Germans, British, Swiss, and all the other fine 20th century machine tool making-countries). We also talked about bed length and swing, and you ain’t got nothin’ if you ain’t got that swing. Let’s talk about the feature set now. If you’re buying new, you’ll shop on these details. If you’re buying used, knowing the differences will help you pick a good project machine.

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Turn Your Lathe Into A Shaper

February 20, 2018 by 16 Comments

Ingenuity is the name of the game with manual machine tools. You often have to get creative to use the tools you have to create the part you want. That’s exactly what happened when [John] needed to cut internal splines and keyways using his lathe.

Lathes are usually used to turn metal, but internal keyways and splines are operations often performed with a broach. An older tool called a shaper would be perfect here, but shapers are relatively rare these days — or are they? There are many examples of shaper attachments for lathes. These are human-powered devices that scrape a bit of metal off each pass. The lathe itself is used to keep the workpiece in place and move the tool in a repeatable way.

Rather than create a shaper jig from scratch, [John] decided to use his compound slide as the shaper slide itself. He removed the compound slide lead screw, which allowed the compound to slide freely. He then fabricated a double hinged bar and bolted this to the compound slide. Moving the bar causes the slide to move. Just add a cutting tool, and you’re ready to cut a keyway. Add an indexing plate, and you’re ready to cut a spline. You can see the tool in action after the break.

If you want to learn more about lathes and what goes into them, you can learn how to build one from scratch.

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Mini Lathe Makes Tiny Hydraulic Cylinders For RC Snow Plow

February 18, 2018 by 20 Comments

You can get pretty much any part you need online these days, but some specialty parts are a little hard to come by. So if your needs are esoteric, like tiny hydraulic cylinders for RC snow plows, you might just have to roll your own.

To be honest, we never really knew that realistic working hydraulics on such a small scale were a thing, but [tintek33]’s video below opened our eyes to a new world of miniature mechanicals. You’d think a linear actuator would be a fine stand-in for the hydraulic ram on a tiny snow plow for an RC truck, but apparently no detail is too small to address in painstaking detail. And as with many things in life, the lathe is the way to get there. Every part is scratch-built from raw brass, aluminum and steel on a mini lathe, with the exception of a few operations that were sent over to the mill that could have been done with hand tools in a pinch. The video is longish, so if you’re not into machining you can skip to 16:40 or so and pick the action up at final assembly. The finely finished cylinder is impressively powerful when hooked up to [tintek33]’s hydraulic power pack, and looks great on the plow. He’s got some other videos on his site of the RC snow plow in action that are worth a look, too.

Ready to take the plunge with a lathe but don’t know where to start? We’ve covered the basics of adopting a new lathe before.

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