So, he told me to come get the darn thing out of his garage... Big Ole Arn!

[Gregory of Sherwood Forest]

You guys may have read my inquisitive posts as I searched for a larger lathe, trying to figure out whether or not to buy vintage, or spring for a new $3k lathe. Well, today the decision was pretty much removed and I should be able to sleep better now (eye roll here).

Most of you know that I buy, restore, and sell old WW hand tools as a hobby. Mostly local, because I like the new owners to try it out and be happy with their purchases, or be able to return them to me if they ever have issues. Well, I got a call this morning from a gentleman who has purchased several old tools from me. He asked if I knew anyone who wanted a big old lathe he's had collecting dust. Of course, I told him that I've been looking for awhile for myself and he said that perhaps we could arrange a deal. I drove over to see what he had, and I got excited pretty quick.

It's a General 260. In pretty darn incredible shape, too.





I was pretty eager, but I tried to keep the excitement out of my voice as I asked him what he wanted for it. His response was, "I want it the hell out of my shop building!" I laughed because I just thought he was being funny, but he assured me that he just wanted it gone.




And then he started telling me more.... All the tooling, vintage Buck Bros turning tools, 4", 8" and 12" faceplates, spur centers, live centers, adapters, and then he showed me the outboard ways, banjo and toolrest (I bolted them on for the picture). Additionally, he has upgraded the motor to a 1.5HP single phase, but also gave me the 1HP 3-phase motor that was on it when he acquired it. Also, he told me to go to the back of the shop and try to dig out the copying attachment that was back there somewhere. Found it, dragged it out and it appears to be almost entirely intact. I may need to find a manual for it online somewhere to be sure.

Pics of the 3phase motor and copy attachment:





(Okay, I can't get the copy attachment pic to show up. I'll try that one later...)


At this point, I was incredulous. You could have knocked me over with a feather.

I told him that I had to give him something for all this, and he said he'd take a jointer plane, if I had one available. So, he'll be visiting me this weekend and I'll be letting him choose one of my several #7's or #8's, and probably talk him into taking a few more things as well. There's no way I'm going to let him go without lots of goodies.

So, we did fire it up while I was there, just to check it all out before transport. The centers aligned perfectly. We ran it for about 10 minutes and there was no heat buildup in the headstock or bearings. Speed range control is perfect. It's all clean and I couldn't find anything wrong at all. Runs pretty darn quiet, too. About the same as my Jet Mini lathe.

Dang. I'm still stunned.


He even let me use his enclosed trailer so I could get it out of his shop today, instead of having to wait a couple more days when I could get back there with another trailer.


Now, I'm going to try it out a few times before I decide on changes I'll be making to it. I really, REALLY want to get full variable speed on it so I can get down to 50-100RPM's for turning large platters. Don't know yet if I'll need a larger 3 phase motor in the 2 - 3 HP range, and run it off a VFD. I WANT that low range, though, regardless of how I have to get it. You folks can feel free to give me some advice. The PowerTool forum has helped me tons so far.

[David Delo]

Congrats on finding such a warhorse of a machine. Hope you get a few hundred thousand more miles out of it.

[AnthonyYak]

It's the wrong color!!
 

These drives are great with the 3 phase motor

https://www.automationdirect.com/adc/Sho...-_575_VAC)

[Gregory of Sherwood Forest]

I've checked those out, and seem like a fantastic option, but I've heard stories about how difficult they can be to get programmed correctly.

What do you think? Should I get a 2-3 HP motor for it, or roll with the 1HP that I just got with it??

[iclark]

I've checked those out, and seem like a fantastic option, but I've heard stories about how difficult they can be to get programmed correctly.

What do you think? Should I get a 2-3 HP motor for it, or roll with the 1HP that I just got with it??

Congrats on the addition to the shop.

Use the 1HP,  but buy a VFD rated for driving a 3HP motor.

You may find that the torque at the lower speed with the Reeve's drive set at ~1/4 speed is all that you need (at least while you are getting used to turning larger stuff).

You already know this, but...
those chisels are tool steel. Getting them too hot during sharpening will pull their temper. Blue is bad.

What are the turning size specs on that beauty and the spindle size? I am guessing that the 12" faceplate is for outboard only.

Are both spindles drilled for a knock-out bar? I did not see one in the tray. If you need to make one, brass or bronze rods are you friend.

[Gregory of Sherwood Forest]

Thanks, I'm pretty happy to have it.

Let's see if I can address all your comments;

Will 1HP really be enough for turning a 2-3 ft diameter platter?? I've bogged down a 1hp on a 2ft platter before using a roughing gouge pretty easily.

I've turned large items before, but just had to use other folks' lathes or the ones at the guild.

I have lots of lathe tools already, the ones in the pic just came with it. I have Sorby, Record, and lots more both HSS and carbide. I sharpen using my Tormek and also with CBN wheels on a 1725 grinder. No issues with heat...

I don't recall the spindle size, but I think it's 1.25", and yes, the 12" faceplate is for outboard only. It'll fit inboard with the gab bed removed, but barely.

I have lots of brass rod as I also have a metal lathe and make lots of brass parts. I'll keep a rod near this lathe for use as a knock out. I didn't notice one in the tool bin, but I could have missed it in all my excitement. There's a lot that came with it. Both spindles are hollow.

[Grey Mountain]

Second opinion.
You suck.
Big time.

GM

[MichaelMouse]

Allow me to echo Grey Mountain. 

Is 1 horsepower enough for a 2-3' platter?  It's a matter of torque, and having a clean downhill cut.  Betting the belt would slip before you bogged a healthy motor.  RPM is about your safety more than anything else, but depending on configuration, you should be alright if the minimum is, as 260-1 http://www.vintagemachinery.org/pubs/363/920.pdf shows 410 rpm with a 3450 motor.  A 1725 would halve that.  With the Nova, turning at 180 makes it seem like I need to shave again after every 10 revs, and IIRC, outboard on the old Delta countered to 300 handled 2' and made me comfortable.  I did help myself out by using the bandsaw, however.  Strongly suggest you do the same.

At 3', you probably won't be able to cut well at all, due to the 6" increase in leverage of the larger radius.  Belt would slip pretty well, I would think.

[TDKPE]

It takes relatively little power to cut, even a heavy one, on a lathe.  But at such a large diameter, you need a lot of torque at the spindle.  The typical VFD operates at constant-torque below synchronous speed (or 60Hz), and at constant-power above that (torque drops off as frequency increases above 60Hz).  But an induction motor will only put out so much torque at rated speed, which is greater than its rated torque (power over speed), but still limited.  So slowing it down with a VFD will make it slow, but won't increase the torque at the spindle beyond what the motor can do, as increased by the existing belt drive reduction ratio.

One way to increase the available torque is to use a higher hp motor.  That's why typical VFD-driven lathes have higher hp ratings than the same lathe with Reeves or step pulley drives.

Another way is to use a 6-pole motor, which is typically rated 1140 rpm at full load.  Such a motor will deliver 1.5 times the output torque as a 4-pole (1725 usually) motor of the same power rating.  So a 1.5 hp 6-pole motor will act like a 2.25 hp 4-pole motor as far as shaft output torque goes, and it'll go 2/3 as fast at synchronous speed.

There are plenty of 1.5 hp 6-pole 230/460V three-phase NEMA frame motors on ebay, mostly for cheap, as there isn't much of a market for them.  Here's a 3 hp motor, which will have the torque of a 4.5 hp 4-pole motor, but it might be too big to fit, and the shaft is likely too large, too.  There aren't many 6-pole motors out there over 1.5 hp (tons of them in industry - just not on ebay), but there are some.

http://www.ebay.com/itm/Brook-Crompton-1...Swr7ZW7Dyb

Oooh, here's a 2 hp Baldor (vented, though, so blow it out with air every once in a while), 1140 rpm, 230/460V.  http://www.ebay.com/itm/Baldor-Industria...SwARZXpNEs

The 2 hp will output the torque of a 3 hp below synchronous speed, and will have a lower max speed than a 4-pole motor.  I used to use a 1/2 hp 6-pole single-phase motor on my little Delta 1460 lathe with 4-speed (standard) belt drive, until I went to a VFD.  The top speed of the standard setup was unnecessary, and the bottom speed was too high for lots of stuff, so the 6-pole was a good replacement motor, but it was still too fast for some of the odd stuff I wanted to try, like goofy natural-edge stumps with a small turned pocket (way out of balance), and things like running a sanding disc at really low speed for HDPE sanding.

Or just look for a used 2 or 3 hp 4-pole motor, which is common as dirt.  Try local motor shops, too - sometimes a motor doesn't get picked up after repair, and they want to recoup their costs.

[Gregory of Sherwood Forest]

Is wiring a 6 pole motor easy enough? Would I still be able to use it with a VFD?

I followed your links, and the prices are affordable. I don't mind sinking a few hundred in this to get it performing exactly like I want, after all, I have nothing out of pocket so far. I'm really looking forward to doing large platters and I don't want to be limited. From what I've trried in the past on other lathe's, I'd really like to get good torque and speeds as low as 50 RPM.

I'll also be looking for an outboard rest stand, Powermatic sells them for $300 or so, but I may be able to have one welded up for me, too. I still haven't dug into the box of tools that came with this. I was busy finishing other items off the HoneyDo list today, and picking up some jewelry for LOML for Mother's Day. After all, she's a keeper. Her response when I brought this home was, "What are you going to make for me with that?".


So, feel free to make exact recommendations. What motor would pair well with which VFD?