Process Notes: Building an Enormous Lathe

We've had a good run, but my lathe and I are coming to the end. 

If you've watched any of my turning videos, you've seen my Harbor Freight 32706. Brand new, this lathe costs less than $300 and that's a stunning value. The 32706 has a 3/4 horse motor, 12 inches of swing, and a cast iron bed. It's pretty insane that they can offer this machine at such a rock-bottom price.

But all good things must end and my lathe is no exception. It's size is good for the price, but it's small by professional standards. I have a lot of projects in mind that need more swing for larger diameter pieces. The motor is also under-powered and it gets alarmingly hot when I turn anything big. I will surely burn it out soon. The lowest speed is way too fast. The sheet-metal stand is flimsy. It vibrates a lot. The cam-locks are wearing out. 

I've ridden this horse as far as she'll go. 

Time to get a new horse!

But then we get to the issue of money. Really good lathes are breathtakingly expensive. If cost were no object, I'd get the Robust American Beauty.

As you can see, this precision monster offers size and construction that most turners can only dream of. With this lathe, I could turn a bowl from a granite boulder. 

But the price clocks in at OVER $8000, so this dream fades pretty fast. 

On the more sane end of the spectrum is the Grizzly GO766, which is a surprisingly big and powerful machine. 

It's not the American Beauty, but it's light-years ahead of my current lathe and the price is a far more modest $2000 (or a little bit less). For what you get, 2 grand is damn affordable. 

But not for me. I make YouTube videos for a living and $2000 is a FORTUNE in my world. So how am I going to get a new lathe? 

I'm going to build it. 

I know it sounds crazy at first. I've built a lathe before (you all saw the videos) and it came out pretty good, but building the kind of lathe I want would be a HUGE project. Too huge. The parts alone would break the bank. 

Or that's what I thought until I started looking around the shop. Turns out, I already own a lot of the parts. I've got a 1-inch steel spindle. It's already bored for a MT2 taper and threaded at both ends. That's a major part right there. The gentleman who gave it to me also included a set of very pricey flange-bearings. So, I've got the precision parts covered. 

I've also got a tailstock ram, several tool-rests, pulleys, lumber for a stout stand, and a number of other odds and ends that will come in handy. I  have a functioning lathe, so I can turn things like hand-wheels, crank-handles, and pulleys. 

I still need the bed and I don't feel like trying to fabricate that. Any lathe of the size and power I want requires a beefy cast iron bed. Nothing less will do. 

But then I was browsing around Craigslist and I found this: 

Hello, gorgeous! 

This bed comes from a vintage metal lathe. It's 60 inches long, 6 inches wide and weighs as much as a small car.  The guy listing it only wants $50 for it. At that price, I'm not even going to haggle. Oh, did I mention that he's throwing in the motor that came with the original lathe? Hitch the mules to the wagon; I'm going to pick that thing up!

Once I saw this bed, the whole thing kind of fell into place. After a few hours in Sketchup, I had this: 

It's pretty straight-forward. The bed is the foundation of the whole thing. I'll weld-up a headstock from rectangular tubing and install the spindle. 

The tailstock can be fabricated from plate-steel and I'll turn a crank and a jam-wheel on my current lathe. 

I already own all the steel and my blacksmithing club includes two certified welders. They're happy to help. 

The final lathe will have 20 inches of swing, 40 inches between centers, and will accept all modern accessories like chucks and centers. This machine might be homemade, but it won't have a lot of compromises. 

The motor that I'm getting is likely to be an under-powered relic and it's single-phase AC, so speed will be an issue. I can make a big counter-shaft arrangement (I've done it before) but that's just a temporary solution. What I really need is variable speed. Oh, and torque; just a ludicrous amount of torque. 

Luckily both 3-Phase and DC motors have gotten cheap. I can probably get a 1.5 hp 3 phase motor off ebay for about $150, shipped. I can also get a Variable Frequency Drive for about $75. That will get me back to single phase power and give me infinitely variable speed with essentially no loss of torque. And that might really be all the money I have to spend. 

$225 for a lathe of the size and power I want? Now that's a deal I can afford. 

I'm sure it won't be as easy as I think, but whatever goes wrong, I'll just make a video about it. That will actually make me money. 

Stay tuned for updates. 

Wish me luck.