What (old) CNC lathe to buy as a starter

Hi, I have a small fabrication and machine shop, and have had to turn away recent jobs at the shop that need even modest quantities of a turned part due to the inefficiency of manually making each one. I have gotten my toes wet successfully with an Arclight Dynamics CNC plasma table and an old (1995) Fadal VMC15, and have been looking to add a CNC lathe if the right deal comes along. I am not looking for massive production quantities or speed - just a way to make multiples of parts more readily. I have seen a number of older but still in use 8-10" chuck machines at auctions going for well under 5K (max target price). I need some input on which brands are still well supported for parts and firmware, and which operating languages are good choices. I use solidworks / HSM works to operate the VMC, so that will be my desired program for the lathe as well. I understand the obvious limitations of older machines in terms of wear or backlash effecting accuracy, parts availability challenges, and cruder operating systems. If nothing else, a list of features or machines to avoid would be a tremendous help. Thanks!

In a very similar spot and I'm seeking a Mazak Quickturn or an Okuma LB-15.

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IMO it is much more important to evaluate each potential machine on the condition they are in. I'd far prefer an off-brand in decent shape with all its documentation over a thrashed big name machine missing its documentation.

Why did you turn away the jobs? Why not outsource the turning parts ?


Anyway on topic. I got an old okuma lb 15. And Iove that machine.

They are very strong and you can get them for cheapish compared to the work you can make with a good one.

Mine is from 1984 with the old osp 5000 and igf conversation. And that control is a million times better than a new Haas or fanuc if you ask me [emoji1787]

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This job was only turned parts. Six different parts in stainless in quantities of 2-20 units with some complex curved features. All parts less than inch diameter and up to 12" long. Customer 800 miles away needed the parts in five days and he was providing the material. He already had a reasonable bid from a shop where he lives... was just shopping a better price.

Even if this were a local job on a normal time frame, the curves were a killer. Multiple hand ground HSS form tools would be my only option... and in stainless on those dimensions I did not see a successful outcome, especially in multiple units. I want to be able to do jobs like this with curved features... hence the search for a cnc lathe. Thanks for the tip on the okuma.

Cole2534 said:

In a very similar spot and I'm seeking a Mazak Quickturn or an Okuma LB-15.

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One think to keep in mind when considering a Mazak is the older controls like a T-2 and T-32 had G-code programming as an option, meaning not all machines had that ability. If you have a budget of $5k, then these older controls are likely the Mazaks in that price range. If you are the type of person who insists on programming using a CAM system, an old Mazak may not suit you.

Me personally, I love my 33 year old Mazaks and the Mazatrol control. My machines have the G-code option and I NEVER use it. G-code seems absolutely archaic compared to the ease of use with Mazatrol.

Okuma lc20 CNC lathe - tools - by owner - sale

Offer a grand for this one. Probably be surprised what it will do.

I have an okuma-howa just like it and it looked just as ugly. $30 spray paint job and it looks like new again. Perfect shape otherwise.

Hi Tatertots:
For the type of shop you are describing, and for the class of work you want to be able to do, I would be looking for a "Teach" or "Toolroom" lathe ...something like the Haas TL1 toolroom lathe, but not necessarily a Haas.
Romi made one that's well regarded, so did Milltronics, so did Haas, and on and on.

The reason is their versatility:
You can set up a 3 jaw chuck or a 4 jaw chuck or a collet chuck easily.
They are manual chucks but for what you want to do...so what.
You can mount a gang setup on the cross slide; you can go with a Multifix toolpost or you can buy an aftermarket turret like a Dorian or Sauter.
You can do chucker work or turn between centers and you usually have respectable swing and respectable center distance.
You can hump in as big a workpiece as you can swing but you can also make piddler parts; just not super efficiently.
You can rig up a bar feeder or a bar puller and do limited production.
You can cobble up homebrew live tools more easily.

The less desirable things:
Typically they have no balls; no rigidity and no horsepower compared to the same capacity turning center.
You will get soaked if you run any amount of coolant.
Your shop will become a pigpen with shit and chips everywhere because the older ones have no enclosure.
They don't survive well in full-on production because nothing is very well protected; not the ballscrews, not the slides
They are a jack of all trades / master of none kind of machine so you will do nothing really well by modern turning standards but you will be able to do a lot of variety, better and faster than you can with a manual machine.

From what you describe as your shop conditions and goals, that's where I'd start.
Cheers

Marcus
Implant Mechanix • Design & Innovation > HOME
Vancouver Wire EDM -- Wire EDM Machining

Not sure what your definition of old is. Personally I would prefer Fanuc controlled machines. Pretty sure around here they have the largest knowledge base. Secondly, the availability of parts goes back 40 years, there are still people selling late 70's vintage 3T series boards on E-bay. Thirdly, Fanuc probably has the largest network of non factory board repair specialists and techs. A lot of support people specialize in different generations of the controller, and have simulators to do accurate testing of components.

Another vote for an older Mazak with Mazatrol. I have an '89 QT8 with T32-2 control, love mazatrol for the simple parts I do. Parts, parameters and manuals are available from Mazak (not cheap, but available). Also there are lots of people on this forum who can give you advice. I'd just advise getting one that has been decently maintained and doesn't have missing way covers or messed up ball screws. Mine was pretty abused and I had to spend more than the purchase price getting it up and running, but I'm happy with it now.

I spotted that Okuma LC20 earlier when searching, and its reasonably close to home. Was surprised by the weight. I have access to a proper trailer, but even if they could load it I am not sure I could get it unloaded at my place... Rough terrain forklift in the #15k load range can be rented here but at a price per day higher than I might offer for the lathe. Everyone loves the bigger stuff until moving day!

I would look for Mori Seiki SL lathes. Avoid anything with a Yasnac control, later ones had fanuc 0m controls, lots of SL's with Fanuc 6T controls out there. If the box ways are good then you'll have a very good machine

Tatertots said:

I spotted that Okuma LC20 earlier when searching, and its reasonably close to home. Was surprised by the weight. I have access to a proper trailer, but even if they could load it I am not sure I could get it unloaded at my place... Rough terrain forklift in the #15k load range can be rented here but at a price per day higher than I might offer for the lathe. Everyone loves the bigger stuff until moving day!

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Most old Japanese lathes are way over 5 metric tons


These machines are build to last

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