# Purchasing a Monarch 10EE Round Dial



## vettebob (Aug 23, 2013)

I found a monarch that has been partially dis assembled it was used in it's previous life to turn motor commutators. Minimum owner will take is $1000
It has taper attachment, 3 and 4 as well as dog chuck and collet closer and collets. Advice appreciated. here are some pics I'm driving 700 miles in the morning to look at it.  Bob


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## DMS (Aug 24, 2013)

If the drivetrain is in good shape, it looks like all the pieces to the carriage/apron are there. For a $1000, would be a good deal if it's not beat to hell. For a 700 mile trip, I hope it works out for you


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## Cal Haines (Aug 24, 2013)

vettebob said:


> I found a monarch that has been partially dis assembled it was used in it's previous life to turn motor commutators. Minimum owner will take is $1000
> It has taper attachment, 3 and 4 as well as dog chuck and collet closer and collets. Advice appreciated. here are some pics I'm driving 700 miles in the morning to look at it.  Bob


Obviously you recognize that there's a lot of work involved in putting this old girl back together.  That said, $1000 is OK for what's in the pictures.  If worst comes to worst, you can sell the tooling, part it out and come out OK.

This was an ELSR (Electric LeadScrew Reverse) machine.  That’s a sought-after option.

What I'm not seeing in the photos:

Feedrod 
Cross-feed dial 
Taper attachment draw-bar  
Apron sump (oil pan) 
Apron pump 
ELSR control rod and related stops and levers 
Collet closer draw-tube 
If you're missing something like the cross-feed dial, you would have a real problem.  I don't know if you'll see this before you finish there, but you'll want to take your time and make sure that you get ALL the parts and have an agreement that the seller will look for any missing parts that he may have once you get her home.

On the plus side, it's well tooled

3-jaw chuck 
4-jaw chuck 
5" dog drive plate 
10" face plate 
Steady rest 
Follower rest 
Collet nose and about 40 collets 
The above is worth at least $700, depending on condition.  Check the backs of the chucks and the bottoms of the rests, if they are stamped with the machine’s serial number you have original tooling (it's unusual to see original tooling and a full set says a lot about the kind of care the machine had over the decades).  The machine’s serial number should be on a rectangular plate on the base, under the tailstock end and is also stamped on the right end of the tailstock flat way.

Don't worry about the motor/generator drive.  They are very reliable and robust.  What problems they have tend to be minor.  I've helped a lot of guys get them running.

Good luck and have a safe trip!

_Cal_


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## RWL (Aug 25, 2013)

I'd want to know why it was apart. A machine in pieces is worth slightly more than the scrap metal value in my book since you don't know that all the pieces are there.


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## vettebob (Aug 26, 2013)

Here's my update   I am the new owner of a 10 EE  It is going to take me a while to sort everything that came with the lathe. It appears to be complete.
The previous owner purchased the lathe from a company that was bought out. He had plans to restore the lathe and even ordered the manual by serial # from Monarch. He got divorced and is selling his house with workshop and is moving back to New York. That being said only the apron and crosslide and the elsr switch cover were removed. It looks like the motor generator was rebuilt not to long ago. This Lathe appears to be complete with every possible accessory except for a toolholder and Turret. I will post pics as I unload and sort everything. My first goal is to reinstall the elsr and see if the lathe runs I think my friend has 3 phase power in his shop.

The ways saddle and cross slide are all worn the spindle turns very smoothly with the belts removed.   Robert


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## drs23 (Aug 26, 2013)

vettebob said:


> Here's my update   I am the new owner of a 10 EE  It is going to take me a while to sort everything that came with the lathe. It appears to be complete.
> The previous owner purchased the lathe from a company that was bought out. He had plans to restore the lathe and even ordered the manual by serial # from Monarch. He got divorced and is selling his house with workshop and is moving back to New York. That being said only the apron and crosslide and the elsr switch cover were removed. It looks like the motor generator was rebuilt not to long ago. This Lathe appears to be complete with every possible accessory except for a toolholder and Turret. I will post pics as I unload and sort everything. My first goal is to reinstall the elsr and see if the lathe runs I think my friend has 3 phase power in his shop.
> 
> The ways saddle and cross slide are all worn the spindle turns very smoothly with the belts removed.   Robert



Bob are you planning a restoration project or "just get it running a make chips"? Just asking because I love following the resto threads and seeing the before and after pics!

Thanks for sharing.


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## Cal Haines (Aug 26, 2013)

Robert,

I'm glad to hear that you bought the lathe.  I hate to see a 10EE go to the scrap yard.

What's the serial number and build date?

_Cal_


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## RWL (Aug 26, 2013)

vettebob said:


> The ways saddle and cross slide are all worn the spindle turns very smoothly with the belts removed.   Robert



Don't forget the scraping class that Richard King is running in PA in December.  It sounds like the machine would benefit from it.


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## vettebob (Aug 26, 2013)

The lathe was manufactured feb 1944 It has a Westinghouse tag on it I'm guessing the original purchaser. The Motor generator looks like a recent rebuild commutators are smooth no ridges or arc pitting everything has new brushes. I reinstalled the elsr . The spindle does have a little play in it, hopefully it can be adjusted out the tach is stuck I'll have to play with it later. All contacts on every relay need burnishing to remove oxidation. This is probably going to turn into a partial restoration. One of the screws for the D1-3 cam lock is missing. Where can I source a camlock kit?
I have some 10 weight spindle oil for my Bridgeport will this work for the spindle bearings? 
My schematic of the power contactor is slightly different than the lathe. I'm working on figuring it out. L1, L2and L3 are the same. L4 wire and a wire piggy backed on to T4 feeds out of the lathe through the same conduit as L1-3. It makes no sense why this was done First pic of contactor. My wiring diagram shows a micro switch in lsr housing (what is that) should go to L4 and a wire should jumper from L1 to L4.


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## vettebob (Aug 26, 2013)

My wiring diagram EE-3320 does not match what is wired.  I figured out why it was wired differently I have a 2 phase motor generator. Now I'm stumped can I make it run off single phase electricity. Robert


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## Chuck K (Aug 26, 2013)

Robert, I don't know what 2 phase is....I'm thinking you mean 3 phase?  No matter what it is, you can make it run.  Mine is 3 phase 440 and I'm running it with my standard residential service.  Congrats on your purchase.  It looks like you have your work cut out for you.  If you happen to have any extra contactor coils in the mix, I would be real interested in buying one from you.  I've been using my machine with only forward spindle rotation for a couple of years now.  Good luck with your project.

Chuck


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## vettebob (Aug 26, 2013)

It is definitely 2 phase power 220 v on the data plate


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## Chuck K (Aug 26, 2013)

I stand corrected.  I googled 2 phase and learned that it does exist although it's not common. I'll be interested to hear about it from someone that knows electrical systems.

Chuck


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## Ray C (Aug 26, 2013)

The following applies to North American electrical systems....

Two phase is not the correct terminology and sometimes, the terms "split phase" or "split leg" is used.  The 220 power that we are familiar with is what comes into our home service panels and it consists of one neutral and two "hot wires".  Somewhere in the neighborhood, there is a transformer with high voltage coming into it.  They put a winding next to the core and it induces 220 volts into the winding.  The two wires from that winding are the two hot wires that enter your house.  If you measure the voltage between those two hot wires, it will read 220 volts.  In the middle of that winding, they put a "center-tap" which is just a wire that connect to the center of the winding.  That wire is the neutral that is brought into your house.  If you measure between the neutral wire and any hot wire, the voltage is 110 but, one with respect to the other is 180[SUP]o[/SUP] out of phase.  Without a significant description of phasor mathematics and something called "complex numbers", it would be very hard for me to describe in other terms why the phase change occurs but, suffice it to say, it does indeed occur.

BTW, the terms 110, 120, 220 and 240 are a little confusing.  110 and 120 are the same really; it's just that the power company is allowed to vary the voltage under different circumstances and it could be somewhere in that range.  The frequency (60 Hz in North America) will not change and if it ever does, there are serious, serious problems going on in at the generation facility -to the extent you will probably see a bright flash coming from the facility.  -Basically, it does not vary and if it does, it happens simultaneously all through North America.  The entire system is synchronized.

Ray




Chuck K said:


> I stand corrected.  I googled 2 phase and learned that it does exist although it's not common. I'll be interested to hear about it from someone that knows electrical systems.
> 
> Chuck


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## Chuck K (Aug 26, 2013)

Ok Ray, I'm kind of an idiot when it comes to electricity.  Are you saying that 2 phase 220 is what I know as single phase 220?  My understanding of 220 single phase consists of 2 hots and a ground. (red, black, and green)

Chuck


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## vettebob (Aug 26, 2013)

Ray it is a 4 wire 2 phase 220 volt motor generator. It is an obsolete power type except in certain places on the east coast. It is completely different from split phase.  Robert


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## Ray C (Aug 26, 2013)

What I'm conveying is that the residential 220 volts that come into our house are technically called "single phase" but sometimes referred to as "split leg" or "split phase".  The originating power on the feed side of transformer is single phase (actually, it is coming from one of the legs of a massive 3 phase transformer that's located at your local power substation) but, through the trick of center-tapping the output side of the transformer, you can split that single phase apart by 180[SUP]o[/SUP].  When it returns to the transformer, it recombines into single phase.  Once again, the mathematics to show this is very time consuming and I consider it a failure on my part to not be able to describe it in understandable terms -and I don't know of anyone whose managed to describe it in non-mathematical terms.

Anyhow, yes, we get 220 single phase (2 hots and a neutral) and it's single phase.  Measuring between the neutral and a hot, you get 110 and measuring between neutral and the other hot you still get 110 but, it's 180[SUP]o[/SUP] OOP with respect to the first one you measured.  You can see this easily with an oscilloscope.

Ray




Chuck K said:


> Ok Ray, I'm kind of an idiot when it comes to electricity.  Are you saying that 2 phase 220 is what I know as single phase 220?  My understanding of 220 single phase consists of 2 hots and a ground. (red, black, and green)
> 
> Chuck



- - - Updated - - -

Four wire 220 is a totally different animal!  I do not think it's available commercially and if it is available, it might be part of a private generation system that is not connected to the North American grid.  It's possible a railway system or some massive industrial complex needs such power and they generate it themselves or, pay the local power company to produce it specially for them.  It is not common at all that I know of but, I am not currently involved in industrial electronics.  My initial pedigree (dual major) was in traditional electrical engineering and physics.

Ray



vettebob said:


> Ray it is a 4 wire 2 phase 220 volt motor generator. It is an obsolete power type except in certain places on the east coast. It is completely different from split phase.  Robert



- - - Updated - - -

One final note...  The neutral wire that comes into your house may or may not be grounded to earth at your house.  It may be grounded to earth at the location of the transformer.  The rules on this vary in different locations and it depends on many things pertaining to the transformer equipment used by your local power company and the distance it's located from your service entrance panel and believe it or not, depends on the soil conditions in your area.  I believe these days, most houses have one (and only one) connection from that neutral wire of your service panel to earth ground.  Having two connections is NEVER a good thing.  -Again, I am not totally familiar with the "rules and ordinances" aspect of commercial wiring.  You need to check with a certified electrician in your area.

Ray


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## Cal Haines (Aug 27, 2013)

Ray,

There is such a thing as 2-phase power.  It's not single phase, i.e. standard household wiring.  It's not 3-phase.  It has two phases, 90 degrees apart, whereas 3-phase has 3 phases, 60 degrees apart.  In the late 1800's 2-phase generators were installed at Niagara Falls and 2-phase power continued in the area until some time in the 1950s.  2-phase systems are usually 4 wire systems.  Engineers figured out fairly early that you could get smoother power and use fewer wires by going to 3 phases.  But by that time there was already an installed base of 2-phase generation, so the system continued.  I've seen one other 2-phase 10EE crop up in the last decade.  Josh, over in the Van Norman & Cincinnati forum, is rebuilding a Cincinnati Toolmaster mill that was originally 2-phase.

According to this, PECO still provides 2-phase service in Philadelphia:
http://en.wikipedia.org/wiki/Two-phase_electric_power


Robert,

A "Scott T" transformer connection can, in theory, be used to run a 2-phase motor from 3-phase.  However, I don't know if it's going to work from a rotary phase converter.  You may be able to find a surplus "Scott T" transformer from a piece of 2-phase equipment that been pulled out of service; check electrical surplus outfits in the Niagara Falls area.  (You would be looking for about a 5kW transformer.)  Is there any chance that the seller has one?

The good news is that with your machine is that a relatively inexpensive solid-state DC drive can be put together to run the original DC spindle motor.  One option is to use a single-quadrant DC drive for the armature and a simple DC supply for the field.  The DC control panel and the big rheostats would continue to be used.  The DC control panel will provide reversing, anti-plugging, dynamic braking and field acceleration functions; the field rheostat would provide field weakening to get the motor above base speed.  There is a gentleman in the UK who's doing just that.

The DC control panel on your machine is the type used on square-dial machines.  You either have a very late model machine or one that's been updated.

The big box on the front of the base, under the tailstock is probably a  rheostat and other wiring for a rapid reverse feature.  I’ve only seen  one other motor-generator 10EE with the feature.  It works with the ELSR  so that the reverse speed can be set higher when threading to speed up  operations.  There is going to be some unusual wiring associated with it  and I do not know of a factory wiring diagram for it.

What is the serial number and build date of the machine?

_Cal_


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## vettebob (Aug 27, 2013)

Cal it was manufactured in February of 1944.  I was thinking about going to a solid state drive to remedy this. The lathe does have the rapid reverse feature. If some one had a motor generator that didn't work I could probably swap in the motor part into mine. The mg was rebuilt in 05 or 06 and the Lathe has sat around for probably the last 4 years. Could you send me a link to the guy going solid state. If I go solid state I want to be able to maintain the elsr features. I thought about the kblc boards but there is probably better out there now days. Robert


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## UncleRuss (Aug 27, 2013)

This is just a educated guess but I would say the MG set is to use 2 phase power to run a standard motor.

Vettbob and Cal Haines are closest to the truth.  Two phase is only available back east and I have read about it but never seen it in use.  Was very popular  or at least used quite a bit in the Ohio PA area in large manufacturing plants.  The National Electric Code has very little to say about it.  I have heard of the Niagara Falls connection in other sources.

Grounding of neutrals.  Neutral conductors are the electrical ground of a system.  The green or bare wire is the equipment ground of a system.  For some time they were allowed to be used for dual use by code such as in ranges, ovens, dryers and such in residential applications.  Since about  the 2006 edition of the code they are once again separated and must remain so.  You no longer have three wire cords going to ranges and dryers.  Now all cords and recps and associated wiring must be four wire.  The change over in existing locations will come via changes and remodels to the premises when inspected by a Electrical Inspector.  So when you add a circuit to the patio and have to rewire the range or dryer or both, don't be too surprised.  

Every neutral is grounded at the main service entrance panel.  This is the only location where the green and white wire may come together.  The transformer on the pole or pad mount is grounded to the neutral.  If you look at the pole where the transformer is mounted there is a plastic pipe or wood cover coming down the pole.  This is to provide physical protection for the ground wire.  There generally is no ground rod.  Once the wire gets below ground level it is wrapped around the butt of the pole six to eight times.

The neutral conductor carries the unbalance of load between the two phase conductors.  If you have two 120v devices.  A phase draws two amps, the second draws two amps.  The neutral carries zero amps. Yo could disconnect the neutral and the circuit could not care less.  When measured at the source.  If you have two 120v devices.  One draws two amps, the second draws three amps.  The neutral carries one amps.  Now here is the real zinger.  In the second scenario if the neutral connection goes away for any reason you loose the votage refernce to ground for the system.  This means the voltage on phase A will be 160 volts and the voltage on phase B will be 80 volts.  Any other 120v items in the system connected to phase A will likely burn up (excess voltage) and any 120v items on phase B will get dim and maybe cease to function.  (under voltage)  Eitherway it is not a good thing.  Either way it is very important to have a solidly grounded neutral in the system at the main distribution panel.  Take a lamp holder and wire Phase A and neutral to it.  Take a second lamp holder and wire phase B and the same neutral to it.  Put in two 60 watt lamps.  Turn it on.  Now disconnect the neutral, besides maybe a flicker nothing changes.  Now de-energize the power and replace one 60 watt lamp with a 100 watt lamp.  Restore power, everything should be fine.  Now disconnect the neutral.  Fun huh?  While doing all this clamp an amprobe on the neutral and see what it reads.

Tried to explain the best I could without math.  I am not strong on math by any stretch but isn't it funny how important it is to both electricity and machining?  Wish my teacher would have said "You will use these trig formulas calculating angles for gears."  Hell I would have probably paid attention.


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## Ray C (Aug 27, 2013)

UncleRuss said:


> This is just a educated guess but I would say the MG set is to use 2 phase power to run a standard motor.
> 
> Vettbob and Cal Haines are closest to the truth. Two phase is only available back east and I have read about it but never seen it in use. Was very popular or at least used quite a bit in the Ohio PA area in large manufacturing plants. The National Electric Code has very little to say about it. I have heard of the Niagara Falls connection in other sources.
> 
> ....




As a matter of curiousity, you've indicated that others are closest to the truth.  I'm curious, do you see technical inaccuracy in the posts I made?  As far as I can tell, all posts subquent to mine are just restatements of what I wrote.


Ray


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## rdhem2 (Aug 28, 2013)

Bless you Ray C.  You made me crack a book.  Never hurts anyone every once in a while.  I find no real inaccuracies in your statement but some terminology I am not familiar with.  To my knowledge "SPLIT PHASE" is a term applied to fractional HP single phase motors and refers to the style/design of the make up of the coil winding.  "SPLIT LEG" I have never run into before.  Other than that I have no qualms about anything in your posts.  Now "WILD LEG" is a term applied to the high voltage leg in a three phase delta supply.

As stated, true TWO PHASE is a four wire affair.  Coming from two separately derived sources, the assembled in a fashion to be 180 degrees out of phase with each other.  For lack of a better explanation, similar to how a DC motor operates except having a rotor instead of an armature.  Consider the coils having a North and South pole orientation but changing polarity sixty times a second.  This then acts upon the residual magnetism of the rotor dragging it around the stator as best as it can.  I don't even know what the design speed is for a two phase motor.  I suppose it is like a three phase motor and depends on the number of poles.  The greater the umber of poles the slower it goes as it does not have to turn as fast to keep up with the phase (magnetism) shift generated in the coils of the windings.

Single phase is derived from a single source with a tap in the center to halve the voltage of the two phase conductors.  In theory you could tap the winding at 1/3 and have 79.92v on one leg to ground and 159.84v on the other, but still 240v leg to leg.  It is all a ratio deal.  Think of a audio transformer with different power outputs.  Same deal.  One lead will put out 100% and another lead will only use 2/3 of the winding for a 1/3 reduction in volume.

On the subject of burned contacts.  I would not file or burnish them unless the surface is so deformed as to hold the contact partially open when energized.  That silver color, yes, it is really silver alloy so why dump it on the floor.  The sooty residue will return the first time you operate the contact under load.  It is a by product of arc flash cause by opening the contact under load.  Once started electricity does not like to quit so until a large enough air gap between the contacts is developed, the current continues to flow.  With DC, as on a ships DC open switchboard, it is very easy to draw an arc and maintain it over the air gap on an open knife switch.  My first mentors used to do just that because they knew it scared the hell out of me.  Ah yes, open front DC switchboards on a rocking rolling ship.  Nice and sweaty down in Auxiliary Pump Room #1.  Those were the days!

Just a flash but why don't we find the voltage of the motor and try to run it direct and eliminate the generator part.  I bet it is just a standard motor.  Thinking from a design point of view the more you deviate from standard, the more expensive the item becomes.  That would never do.  The engineers I used to work with would always say "Looks nice, what did it cost to do that?"  After I would give them a figure they would say "Fine, now figure out how to do it for half the price."!  The pictures of the control show it to be very, very old equipment that is probably do for a refresh also.  Folks don't think of it but electrical components wear out too.

To be honest my man, I have tried to be real accurate to the best of my limited knowledge especially after I saw the double "E" connected to your name!  On the other hand a good friend of mine is a EE for the Bonneville Power Administration and when he offered to help me trim a house he ask for terminal strips to connect the wires as he had never heard of wirenuts.  Course he had not been out of school too long at the time but I still tease him about it.


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## Ray C (Aug 28, 2013)

And even now, there is something called "restless leg".  It's a medical syndrome, they don't know what it is but, they sell medication for it.  -Go figure.  .


BTW: Don't worry about the "EE" stuff.  On my posted resumes, I only list the degrees which are applicable to the job.  I don't really consider myself an EE but can do the work if called upon.  I've spent a lifetime learning and doing; followed by doing and learning...  -and that's what counts.


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## Cal Haines (Aug 28, 2013)

*An Introduction to 10EE Motor/Generator (MG) Drives*

For those not familiar with motor/generator (MG) 10EEs like Robert's,  here's how they work:

The MG consists of an AC motor (typically 3450RPM and 4.6HP) that drives a DC generator (typically 2.5kW) and a DC exciter.  The spindle motor is a 3HP DC motor with a large number of poles.  It will provide continuously variable, silky smooth power at the spindle from about 8 RPM up to as much as 4000 RPM (depending on pulley ratio).  The spindle motor is coupled to a 6:1 back-gear unit, giving it a low speed range of about 8 to 700 RPM.  The exciter is a self-exciting DC generator that provides 115VDC (230VDC in the first generation machines) to power the relays in the DC control panel and the generator and spindle motor field windings.  The DC generator is always built on the same shaft as the AC motor; first generation machines also had the exciter on the common shaft.  The generator provides current for the spindle motor's armature.

Variable speed control is via the Ward-Leonard system:  Below the motor's "base speed" the spindle motor's field is at full voltage (115 or 230 VDC) and its armature voltage is increased by controlling the generator's shunt field voltage.  At base speed, the MG provides the spindle motor with full field and armature voltage.  The spindle motor's base speed is 690 RPM at an armature voltage of 230VDC.  To get the motor to run faster than base speed, its shunt field voltage is reduced (which seems counter-intuitive); this is called “field weakening”.  The maximum speed of the spindle motor is typically 2400 RPM.  The ratio of the pulleys installed can provide maximum spindle speeds from 2500 to 4000 RPM (machines have only one pulley ratio).  Below base speed, the spindle motor operates at constant torque; above base speed it provides constant HP.

Control of the generator and spindle motor fields is by a specially wound, ganged pair of 500W Ohmite rheostats:  The spindle motor armature (generator control) rheostat is configured as a potentiometer to directly control the voltage to the generator’s field.  It varies from about 700 Ohms at low-speed end to 0 Ohms at mid-range and above.  The spindle motor field control rheostat is connected in series with the field and has a resistance of 0 Ohms for the first half (low speed) of rotation, then increases to 300-400 Ohms at maximum speed.

_Cal_


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## Ray C (Aug 28, 2013)

Cal,

Thank you. I've heard dribs-and-drabs of how they were designed but never had such a full understanding until reading your post...  Thanks...

Now, I'm curious...  Why did they go to such trouble and what did it buy them?  Certainly by then, AC motors were good, gear design was very mature and so were sophisticated gearboxes and transmissions.  Just curious about why they went this route...  Any ideas?


... Don't wish to derail the topic too much but, my father had a Monarch at his company and I do believe (but I could very well be mistaken) it was all driven with hydraulics.


Ray


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## vettebob (Aug 28, 2013)

Boy;  I started quite the discussion on different power Types. The reason you weaken the field on the motor is to reduce the counter EMF( electro magnetic Force) this is what indirectly  keeps the current going thru the armature in check. There is always a balance between the armature and the field on a motor. That's why people burn up power tools when they load up the motor it slows down. The magnetic field can't keep the current in check and the size of the wire the armature and or field are made of can't handle the additional current flowing thru it. I know this is a over simplification but it gets the point across. When the motor is stalled it can only sustain this condition for a certain amount of time it is called (locked rotor current).

Hope it helps  Robert


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## Cal Haines (Aug 29, 2013)

Ray C said:


> ...
> Now, I'm curious...  Why did they go to such trouble and what did it buy them?  Certainly by then, AC motors were good, gear design was very mature and so were sophisticated gearboxes and transmissions.  Just curious about why they went this route...  Any ideas?
> 
> ... Don't wish to derail the topic too much but, my father had a Monarch at his company and I do believe (but I could very well be mistaken) it was all driven with hydraulics.
> ...


Hi Ray,

The benefit of the 10EE's drive was continuous variable speed.  I don't know that the 10EE was the first variable speed toolroom lathe, but it was certainly an early entry.  The problem with a gear-head lathe is that the vibration from the gears can make it impossible to get a good surface finish on some materials.  The ability to easily vary speed is quite nice.  If you're experiencing surface finish problems you can often change the speed a bit and get it to go away.  Anyway, the market spoke and variable speed toolroom lathes were in high demand, with multiple companies producing them.  The 10EE's reputation is built in large part on its variable speed drive.   Monarch still builds 10EEs.

Reeves drives were around, so they could have gone that route I suppose.  I doubt we'll know why they made their choice.  Perhaps they couldn't get the low speed torque that they wanted with a Reeves drive?

You're correct:  the first generation of 10EEs had a hydraulic Sundstrand Hydrostatic Transmission drive.  It wasn't a terribly successful drive and was replaced within a few years by the motor/generator (MG) drives.

Monarch didn't make the MGs.  They bought the MG set and spindle motor from Reliance.  So they had a proven system that they could buy and install in their lathes.  By the time the made the switch they were gearing up for WWII.  AFIK, Monarch designed the DC control panel which controls the MG system.  Following WWII Monarch developed their own tube-based electronic controls but retained the Reliance DC spindle motor.

_Cal_


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