Frame for lathe and mill

[cejm78]

On cejm78 Said:

I have been talking to Peter Symonds at Inverter Drive Supermarket. Somebody recommended him, as he knows a lot about Warco machines.

Whilst my lathe is a 440v machine, the motor can be rewired to 240v without the need for VFD.

I have read on here that a 3 phase machine gives a nicer finish compared to a 1 phase machine. As it is only a hobby lathe, I don’t think it will make much difference to me.

For the time being, I will rewire the motor to 240v. If, in time, the finish becomes an issue I can always rewire it back to 440v and install a VFD.

Did you supply Peter with the wiring diagram that I mentioned in this post?
It may of course be that Warco have changed something, but I’m struggling to work out how to run the lathe off single phase 220v

Looking at mine won’t help, as that’s single phase from new.

Warco GH1330 question.

Bill

[BazyleParticipant @bazyle]

There might have been a misunderstanding about not needing a VFD. There are VFDs for 240v 3phase and more expensive ones for 440v 3 phase.  A modern 440v motor can normally be converted to 240v quite easily (therefore likely to be so for a Warco machine) but it will still need a 240VFD. Amateurs rarely want the expense of a 440VFD. An industrial user might want the speed control of a VFD but accept the extra cost to keep all their machines ‘standard’ or to readily move the VFD to other machines.

[Bazyle]

On Bazyle Said:

There might have been a misunderstanding about not needing a VFD. There are VFDs for 240v 3phase and more expensive ones for 440v 3 phase.  A modern 440v motor can normally be converted to 240v quite easily (therefore likely to be so for a Warco machine) but it will still need a 240VFD. Amateurs rarely want the expense of a 440VFD. An industrial user might want the speed control of a VFD but accept the extra cost to keep all their machines ‘standard’ or to readily move the VFD to other machines.

This is part of the reason I referred back to the wiring diagram.
Assuming it’s still correct, the three phase 440v version of the lathe uses contactors/relays etc. so the switching and safety cutouts etc will stop the motor whilst still under load. Many VFDs don’t like that on a regular basis.
There’s also the machine lamp and the coolant pump motor.
It’s not as simple as just adding a 220-220v VFD as the control circuitry will need re-wiring too, in order to prevent detaching the motor under load.
It may be easier to use some sort of a 3 phase supply box, be it Transwave or something from Machine Mart.

Bill

[duncan webster 1Participant @duncanwebster1]

Or just buy a package. VFD and pendant control box from Newton Tesla. Connect to the motor, plug in and go.

 

[Howard LewisParticipant @howardlewis46836]

A suitable motor on a 3 phase supply will produce a better finish, because it runs more smoothly than a single phase motor, (each winding gets 3 impulses per rev, rather than just one).

A V F D varies the motor speed because it varies the frequency of the impulses.

A lathe, because it moves a tool across the rotating metal actually produces a helix.

On a finishing cut, it might only be 0.001″ (0.025 mm) deep, and 250 /inch (0.0393 mm pitch) but it will be a very shallow, fine pitch, helix.

A tool with a minute radius on the nose will make the finish even better

H T H

Howard

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