Thread: New (Old) Sheraton CUB Lathe

Originally Posted by toolman49

In the chip tray of course.
See yuz.

How did i not see that one coming

Originally Posted by Ropetangler

The second option of a Rotary Phase Converter, can be a good call, especially if you have, or plan to get a multitude of 3 phase machines. You only need one of them to run a heap of other machines. The $1600 is probably fair for all new parts, but people have built them for way less than that, - it all depends on how good you are at scrounging the bits. 3 phase motors from scrap yards, often the switched and plugs too, and transformers which started out as welders which could be run on single or 3 phase will be much cheaper than new parts, if obtained as scrap parts, and have been used in the past for projects like yours. There is an old thread in these forums about one such build, I will try to find the link for you.

Wayne I haven't been able to find the thread I was looking for which described the authors build of an RPC with a 415V 3 phase output. In it he used a transformer out of an old welder, -I think it was from a TransArc Tradesman, but am not certain of that. However Greg has done something similar, and I'm sure that he would assist you with some advice on how he built his, if you decide that you might go that way. Regards,
Rob.

If you're in suburbia, there's a good chance 3 phase is already on the street anyway so no expensive transformer (unlike Rob & myself). Your meter box may need upgrading though, but it probably needs it anyway so not a bad thing regardless. That's what I did for my Sydney house.

90A per phase is plenty, 60A is quite adequate.

As I said and Greg also said, if you go the VFD route *none* of the existing lathe wiring is going to be useable. Power cord to VFD, VFD to motor, remote speed control pot to somewhere convenient, on/off buttons on VFD, that's about it. The VFD lets the magic smoke out if you start/stop the motor or plug-reverse it by means other than its controls. Or so people say, I've done it by accident and the unit survived but it was a GEC Ranger 5kW VFD running a pathetic 370 watt motor. The VFD was free, you see...

Initially it'll probably be cheaper to go the VFD path. If you get a serious tool habit, the equation changes. With 415V 3 phase, there's a *lot* more stuff you can buy and just plug in.

PDW

Originally Posted by PDW

, if you go the VFD route *none* of the existing lathe wiring is going to be useable

Now that all depends what you mean by "wiring". All of the control wiring of my mill is still there and in use. The contactors now just run the VSD instead of switching the 3 phase. Now a simple machine(like my shaper) the contactor was 415V so in that case it goes. So it depends whats inside that control box.

Stuart

Originally Posted by Stustoys

Now that all depends what you mean by "wiring". All of the control wiring of my mill is still there and in use. The contactors now just run the VSD instead of switching the 3 phase. Now a simple machine(like my shaper) the contactor was 415V so in that case it goes. So it depends whats inside that control box.

Stuart

Yeah, true, but IMO it's going to be a lot easier to ignore what's there, put the VFD somewhere close to hand, run the cable from the wall outlet to VFD, VFD to motor and just ignore everything that exists. That's what we did when we put a VFD on the lathe at work some years ago. Dead simple to swap back if the machine gets sold or relocated to a place with 415V available.

KISS......

PDW

Bryan,
must be a good lathe if it features on the cover of the first year bible.
Kinda makes it a 'cover lathe'. Did you check if it is also a centrefold

Phil

G'Day Wayne,
Just an old fart thinking aloud, depending on the work you are planning to do and the tooling you intend to use, could you get by with a single phase 240 volt motor ?, I saw a new 4HP motor on Ebay recently for about $150, there would be a fair bit of work rewiring the control gear but it could be a simpler solution (yes I know that single phase motors are not as smooth as 3 phase).
Regards,
Martin