You would want to buy a 3 phase lathe, and then add a VFD if it is not available as a factory option. You can read through the post below which gives some details of how to do it. See post #89 for the last set of updated documents. This basically applies to the PM-1236T, 1340GT and there is a separate posting that applies to the 1440GT. PM/QMT offers two 1440 lathe models with factory VFD's, I wold recommend going with a factory VFD for the PM-1440-2SM-V or PM-1440BV if you are looking at mainland China lathes in that size. As I mentioned, I think the former PM-1440-2SM-V has many nice new features, but a number of other people have previously bought the PM-1440BV and I haven't heard of any issues/concerns with it. The 1340GT would be my recommendation in a Taiwanese made lathe with higher build quality, but they will all turn metal to the same accuracy.
The basic VFD install using the factory 3 phase motor is probably going to run in the $800-1K when you are all said and done. What I call the basic VFD conversion works well, but only recommended for new lathes where the contactors have not been used. It also requires basic knowledge of electrical wiring. A few people have bought the single phase models of the lathe because they where available, but there are very few 3 phase motors that will fit the motor space, and figure another $400-600 for a 3 phase motor. All of this has been previously posted if you do a search in this forum.
If you are just starting out, I do not recommend buying a used lathe, unless you are very mechanically inclined and do not mind spending a lot of time and money restoring it. The other recommendation as tailstock4 mentioned, pay a bit more up front, do not scrimp, i.e. buy once - cry once. If you buy poor/cheap equipment, chances are you will be unhappy and eventually replace it down the line, it will cost you more in the long run.
Lathes also require a lot of additional accessories to make them functional, and you need to include a substantial budget for the additional tooling and chucks. I would figure at least another $2-4K in additional costs. Decent chucks is important, the PM-1440-2SM-V comes with a Set-True type of 3J scroll chuck (the typical generic Chinese chucks that come with the less expensive lathes usually become door stoppers), I would add the PM 4J Taiwanese independent 8", and also the PM Set-True type collet chuck (either 5C or ER40, David Best has a white paper on the pros/cons of each) which is used for smaller diameter stock. The PM/QMT chucks offer very good quality at a reasonable price. If you go with say Bison, TMX, PBA or similar higher end chucks it will cost you 2-3X more. Cheap chucks, are just that, so don't complain when you have issues with them. Last but not least do not buy cheap turning tools, or sets, you will only be disappointed. David Best has written a book which demystifies the topic, and outlines recommendations on indexable tooling, it will pay for itself with your first indexable tooling purchase.
Many individuals buy the PM1340GT lathe as a 3 phase machine with the intent to convert it over to a VFD system, the usual VFD that is used is the Hitachi WJ200-015SF. Unfortunately the conversion often requires a somewhat complex and costly conversion process to optimize many of the VFD...
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I know I have read that the motor area is a tight fit, but is it possible with some extra work? My lathe is up against a wall so I cant really look right now. I want to do a 3ph conversion but also want more power at the same time. With the larger stock I've been turning lately i am constantly...
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