Which CNC lathe should I get?

Hello, I need to make custom water fittings with threads and also make quick disconnect couplings.
Which CNC lathe will be best for this? I'm on a tight budget around $5K.

I hope I can find a used CNC lathe, that'll work out from the box without repairing.

Thanks.

It's not really a matter of best, it's a matter of what machine will do the job.

You have to consider:
Spindle horsepower
Work envelope
Spindle bore
What material types you will be machining
What power you have available
Is live tooling required
and a bunch of other stuff I am forgetting

Then once those questions have been answered, you can start looking for a machine that will meet the requirements.

Materials: Plastics, Copper, brass, aluminium and stainless steel.

Power: I have single phase 208V/120V delta wye, but I can also upgrade to 3 phase with 440V/277V delta wye which could take 2 weeks.

Live tooling is required but not necessary.

OK, pretty much the full range of materials. Sounds like you have adequate power.

Work envelope / spindle bore required (expected size of parts)?

I looked through your threads on The Hobby Machinist and now I understand what you are doing.

I really don't think that a CNC lathe is what you want, at least not yet. Maybe a CNC/manual lathe. But those lathes really don't exist in a usable form, there are some that have cranks attached to the stepper motors, but no manual threading capability or other normal functions. You would have to start out with a manual lathe and add the CNC hardware to it. That little 1224 Jet would make a great base for a CNC/manual lathe, and a perfect size for your needs. I would build it to change between manual and CNC with a flip of a switch, keeping all of the original functionality intact. This would allow you to do manual machining as needed for prototyping and still use the CNC threading flexibility when needed.

All of this could be done within your budget.

I don't know if you are using any CAD software but I like Fusion 360, which also has built in CAM software with pretty good turning functionality, and it will generate any thread profile you want. It's still free to startups, hobbyists and students.

Quote:

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Originally Posted by Jim Dawson

I looked through your threads on The Hobby Machinist and now I understand what you are doing.

I really don't think that a CNC lathe is what you want, at least not yet. Maybe a CNC/manual lathe. But those lathes really don't exist in a usable form, there are some that have cranks attached to the stepper motors, but no manual threading capability or other normal functions. You would have to start out with a manual lathe and add the CNC hardware to it. That little 1224 Jet would make a great base for a CNC/manual lathe, and a perfect size for your needs. I would build it to change between manual and CNC with a flip of a switch, keeping all of the original functionality intact. This would allow you to do manual machining as needed for prototyping and still use the CNC threading flexibility when needed.

All of this could be done within your budget.

I don't know if you are using any CAD software but I like Fusion 360, which also has built in CAM software with pretty good turning functionality, and it will generate any thread profile you want. It's still free to startups, hobbyists and students.

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Thank you for the helpful information.

For some reason it is extremely difficult to find any literature or information about the engineering and design for quick connect couplings.

Would you happen to know any good books (yes, please plenty of books) that has wealth of information about the proper designing of quick connect couplings?

I'll be using solidworks.

Thanks.

I think there are no books on the subject, it is not really the type of thing that books are written about. There most likely 100's of different styles. I'm sure I have a dozen or so different types in my shop, from lab type connectors to heavy hydraulic, some self sealing on disconnect and some not.

I think your best source of literature is manufacturer catalogs, and it may be possible to find some white papers on the subject.

Quote:

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Originally Posted by Jim Dawson

I think there are no books on the subject, it is not really the type of thing that books are written about. There most likely 100's of different styles. I'm sure I have a dozen or so different types in my shop, from lab type connectors to heavy hydraulic, some self sealing on disconnect and some not.

I think your best source of literature is manufacturer catalogs, and it may be possible to find some white papers on the subject.

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Thank You,

How are these tiny little holes are made into the inner walls of the coupling where the ball bearings fit into?
(I uploaded a picture)

Also do you think I'll be able to make few pieces of quality flat head quick couplers with a precision manual lathe?

Thanks.

In production the holes are most likely drilled with the lathe live tooling, using the C axis for indexing. Most likely done on a Swiss type CNC lathe.

With manual machines, they could be drilled on a milling machine or a drill press using a Spindex, horizontal rotary table, or spacer.

No reason you couldn't make those on just about any manual lathe, just requires a bit of practice to learn the needed skills.

On the expensive commercial 3, 4, 5 axis CNC lathes, what kind of motion mechanism is used for tool head to move along the x, y and z axis, does the industry use ball screws, lead screw or micro stepped belts used in 3D printers for motion along the axis?

Thanks

Quote:

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Originally Posted by rajhlinux

On the expensive commercial 3, 4, 5 axis CNC lathes, what kind of motion mechanism is used for tool head to move along the x, y and z axis, does the industry use ball screws, lead screw or micro stepped belts used in 3D printers for motion along the axis?

Thanks

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High precision ball screws.

Quote:

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Originally Posted by Jim Dawson

High precision ball screws.

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Thank You.