New Lathe

I have a PM1440GT which covers 99% of my current needs. My previous home lathe was a 1324 so it was a big step up. I really like my 1440GT but at the current price, if I were looking for a hobby lathe today, I would seriously consider the 1440GS. Lots of features for the price.

If you have the space a 1440 size, IMO, is the sweet spot for a hobby lathe. Having more capacity opens up more opportunities for what type of work you can do. It is not so big that it feels awkward to do small stuff or so small you will be wishing for more.
 
Thank you all for your input. Much to think about. Is a variable speed worth the $ difference?
 
I have the 1440gt also and to me I dont see where a variable speed would be worth a dollar difference.
 
I have a vfd conversion on my 1440gt. I did the vfd conversion for the 3 phase motor, soft start, electronic breaking and the FWD/REV jog feature. While I also have mine setup for variable speed, most of the time I just change gears. The variable speed can come in handy for fine tuning a particular material that prefers a rpm other than the set gear speeds. I have not found that to happen very often. I know others with vfd conversions who do most of their work within a certain rpm range and will set the gear somewhere in the middle and then adjust with the dial. My old lathe was a 1.5 hp variable speed and I found it struggled at lower rpm work. I have no experience with the PM1440BV so it would be good to hear from someone who owns one as to how it performs.
 
I think all motors will struggle when they are slowed significantly using electronic variable speed. My problem with buying a machine that relies on variable speed electronics, sooner or later the electronics will fail. The same electronics will likely not be available. Likely some one will be able to find a fix but it will cost. Gear driven machines will run a very long time W/O failure. If you feel you really need the speeds between what the gears can give you, add a separate variable frequency drive. My lathe (PM1440HD) has 12 spindle speeds from 40rpm to 1800. As a hobbyist, that has met all my needs. My most commonly used speeds are 325, 460 and 650. 1800 is scary fast! Maybe using VS when facing a big part would be ideal but none of the "real," translate professional, machinist that I know have VS on their lathes. Maybe you should try asking Keith Fenner, Oxtool, Thatlazymachinist or Robrenz what they think. They all have heaps of experience.
 
Before you jump into electronic VS on a lathe take a look @ a video by blondihacks.com where she has problems with electronics on her mill. My lathe has 12 spindle speeds (PM1440HD) that have met all my requirements. 40rpm to a scary 1800.
 
Factory VFD machines are usually 2-3 speeds, the motor are often the next size up to handle the RPM extremes. I do find that adjustment on the fly is advantageous for things like boring/drilling where there is a sweet spot. Also when you cut down in diameter you often turn up the speed to maintain SFM. The soft start, slow jog and electronic braking are all worthwhile. Just like using a DRO, died in the wool say it is one more thing to go wrong, those that use them always say I should have done it sooner. Nice to have, but not a must have.

As far as things breaking/longevity, I have yet to see a VFD fail in 10+ years other than the cheap Chinese brands. People are still using VFDs that are 2+ decades old and pretty darn big. They all work pretty much the same, they are controlled by programmed inputs and that isn't going to change in the near future. I will probably be long gone by the time my VFD goes south (the rated service life on the Yaskawa's is something like 27 years). In the mean time I get to enjoy all the benefits of the VFDs. Eventually it will be cheaper to have these mechanical machines electronically controlled and eliminate gearboxes, change gears, etc. to a major degree. My factory VFD mill is a direct single speed belt drive, with just a back gear, all the controls are electronically controlled. Yes, I think VS is worth a small premium, but it is the rest of the machine that is determining the decision.

You can compare numbers, but at the end of the day until you start getting your hands on a machine it is hard to appreciate the differences. You also need to factor in that the lathe accessories can cost almost as much as the machine at the end of the day. You want a D1-4 or D1-5 chuck mount, the latter is required for the larger spindle bore, chucks and back plates are available in both sizes. Most people end up with a 3J scroll, 4J independent and usually some form of collet chuck for smalls. Some lathes come with chucks, the Chinese mainland chucks tend to be poorer quality so you may want to get better chucks. Get a QCTP and a buch of holders. Most of use use a BXA size QCTP, which is a very common size. Bigger machine may need a CXA (next size up), 1236 might fit a BXA. Size matters as to availability of tooling. It is a deep rabbit hole from there, and a long learning curve.

Probably focus on the 1340GT, 1440BV and 1440GS. Capacity wise they are all close, the 1340GT is the most popular. No change gears other than for metric, the Norton gearbox is primitive but has been used for decades. Fit/finish is significantly better, but a few less features. My major concern with the 1340GT was the lack of braking, this was solved with the addition of a VFD that will stop the chuck in 1 second.
 
mksj said:
Just like using a DRO, died in the wool say it is one more thing to go wrong, those that use them always say I should have done it sooner.
Click to expand...

I learned to ignore those folks a long time ago, after having to listen to my grandpa go on and on (and on) about how all this new fangled stuff is junk, won't last, etc., etc, ad nauseam. If folks listened to him we'd have never gotten out of the bronze age. ;)
 
Seems like putting a good VFD on a geared machine would offer the advantages of both. I'm still leery of Chinese electronic controls. So I wouldn't want a machine that relied on them to remain functional over many years. One thing that would be really nice, putting an additional gears on the quick change gear box that converted the lead screw to metric.
 
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