# Clausing Lathe Question



## HighWall (Jan 4, 2016)

Greetings.  I've found these fora to be quite helpful although most of my time has been spent in other areas.

Sadly, my father in law, a master gunsmith, is passing on his Clausing (I believe he said it was a tool room lathe) to me.  It's been lovingly restored and is somewhere in the 12x36 size range.  I'll be able to get the actual model number soon.  There is a TON of tooling that comes with it, so nearly any expense to get it moved into my shop and running reliably would be worth it.  It has a 3 phase motor which he always used with a rotary phase converter.  Electricity isn't my strong suit, but it's like he's using another electric motor to convert the power from single phase to three to keep the lathe motor happy.  I've never felt a lot of confidence in this system, although he used it for decades with notable success.  I'm sure he went that route as an economy, but I understand there may be better solutions now.

I only have single phase power in my shop as well, but if I could get some kind of reliable converter OR change the motor to something that would be more suited to my situation, I'd love to hear about it.  I'm coming from a G4003G which I've had for a few years, but these older tools are a bit different.  I am considering a DRO because that's what I've been most comfortable with, although it may be a little incongruous on a classic like the Clausing.

Perhaps this is a topic that's been beaten to death.  If' that's the case, please forgive me for not making an adequate search.  I expect I'll have more than one or two questions as this process unfolds.


----------



## wa5cab (Jan 5, 2016)

Actually, the standard US residential wiring is single-phase with the pole transformer center-tapped and the center tap grounded to provide two 120 volt and/or one 240 volt circuit.  A Two-phase system (not common any more and was only common in certain servo systems) usually has a phase angle of 90 deg.

Three-phase power sytems have some advantages over single-phase ones.  The main one being that you can run three-phase motors which have advantages over single-phase ones.  However, it is very rare for utility companies in the US to supply three-phase power to residences or to small businesses in single family residential areas.  Mainly because it's both cheaper and they make more money.  

There is nothing wrong with the rotary single to three-phase converter that your father had.  They are or can be if matched to the load more efficient than so-called static converters.  And produce cleaner three-phase power.  If it works, I wouldn't fix it.  If you get ambitious and decide to switch to a VFD (variable frequency drive), you won't have to change the motor(s).


----------



## HighWall (Jan 5, 2016)

Thanks for the information.  I think it's a VFD that I was thinking of.


----------



## Silverbullet (Jan 6, 2016)

Why mess with what's been working for years .if its working run it till it gives you trouble . then I would go with a VFD they are the newest rage but seem to be very good. I had a lathe set up like that many years ago and it seemed like I didn't raise my electric bill more then 10 bucks and I ran it every day back then.


----------



## HighWall (Jan 6, 2016)

That's a good point.  It seemed kinda makeshift to me, but now I see it's a common practice.  My father in law has been notoriously frugal and sometimes made inconvenient choices to save a few dollars.  Nothing wrong with that, but if I'm going to invest a bunch of time learning a new system, I'd like it to be as good as it can be.

That's not to say it's not a great tool.  You know those threads where an owner of a vintage tool restores it to near showroom condition?  That's what this is like.  He lavished much time and skill in the process.


----------



## wa5cab (Jan 7, 2016)

The main reason that the rotary single to 3-phase converters fell out of style was that the static converters (which basically became practical to build through improvements in capacitors during WW-II) are smaller and cheaper and do work well enough to use.  3-phase motors weren't cheap.


----------



## HighWall (Jan 8, 2016)

I've since determined that this lathe is a Clausing 5914 with the VS drive.  The hydraulic system is fully functional, although it does leak a bit.  My father in law says it isn't a problem in working with the lathe as hydraulic fluid is cheap and you just keep it topped up.  If it every becomes a major problem, I'll most likely convert to VFD, but use it as is for the time being.


----------



## Cheeseking (Jan 8, 2016)

Will a vfd reverse the lathe instantly?


----------



## wa5cab (Jan 8, 2016)

No.  Or at least not safely.  In the limit, as the time goes to zero, the instantaneous current should go to infinity.


----------



## JimDawson (Jan 8, 2016)

Cheeseking said:


> Will a vfd reverse the lathe instantly?



Close enough to be practical.  A VFD with a braking resistor should reverse almost as fast as switching a 3 phase motor into reverse, but with better torque control.


----------



## Cheeseking (Jan 8, 2016)

If the vS works the way i remember, the only problem with  hydraulic leak besides bit of a mess would be the speed changing on you due to reeves drive creeping.   I asked about reversing since I like to power tap on mine so capability of reversing on a dime is very handy.   Three phase motor, RPC and geared head work great in this application.   I set lathe to 50 rpm, chuck the tap semi-tight in the drill chuck and leave the lock off.   Works wonderfully and saves a ton of twisting by hand.  Tap usually just slips if something goes bad.   As far as the current load, I agree it does spike.  How could it not right!  It also puts a bit of strain on the gear train abriptly reversing.   I made sure to design my 3phase electrical system stout enough to handle it tho.   Every thing is overkill, NEMA rated, way heavy conductors, fused to the point of ridiculousness,


----------



## Colchester lathe man (Jan 31, 2016)

Hi, If you need any parts or manuals for your Colchester lathe, please let me know. I can help you.
My name is Frank with FDK 3 Company and my phone # is 713-202-3551.

Thanks


----------

