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  1. #21
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    In regard to a VFD conversion without a back gear, has anyone looked into running vector duty TENV 900 or 1200 rpm 230-460v motor with a 460v input to increase the range ? A 5 hp motor of that type can be found pretty reasonably ( mine was NOS $400 but I scrounged for it ). Transformers are pretty common on the used market. Performance would start to erode at about 2200-2500 rpm but would still be decent at 3600 rpm. If not enough, a 7.5 hp motor can be had in the same 184 frame size or 213 if necessary. Dave

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    without the backgear, for sure you want a 900 RPM motor.

    With an AC motor you have constant torque so as you cut speed you cut HP. About the best you can do is 5% rated speed. So a 10 HP is now a 1/2 HP motor. You need about that much to run the machine for threading.

    Now top end is just a function of centrifugal force to blow the motor up. 900 RPM motors are built the same as 3600, just different wiring connection.

    So you can run a 900 RPM motor from about 45 RPM to 3600 RPM. maybe should go more like 7% on the bottom so 60 RPM for bottom. Now I suggest belting it about 3:2 so you end up with 40 to 2400 RPM speed range.

    Of course more speed range is possible with the back gear and much cheaper smaller 1800 RPM motors are fine.

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    Quote Originally Posted by beckerkumm View Post
    In regard to a VFD conversion without a back gear, has anyone looked into running vector duty TENV 900 or 1200 rpm 230-460v motor with a 460v input to increase the range ? A 5 hp motor of that type can be found pretty reasonably ( mine was NOS $400 but I scrounged for it ). Transformers are pretty common on the used market. Performance would start to erode at about 2200-2500 rpm but would still be decent at 3600 rpm. If not enough, a 7.5 hp motor can be had in the same 184 frame size or 213 if necessary. Dave
    Peter Haas covered the progression way back in older threads. IIRC "the factory" tried for a time to run with a TEN HP AC motor to eliminate the need of the reduction gearbox. They went back to a 7.5 HP and the gearbox.

    The challenge is the AC induction motor is a "frequency slaved" animal or tries to be but is allowed to "slip". It tries for constant Torque, but the torque is not it's "prime directive". Hz are the "boss".

    A straight-shunt wound DC motor is "torque slaved" animal with constant RESERVE torque. RPM is the by-product, not the boss. It has no lock on RPM. So it has the full ration of reserved torque on-tap to back up increasing demand as the load increases.

    All by itself, the MOTOR doesn't CARE if RPM drops. The drop is what asks for more power as CEMF drops! Straight shunt is GOOD at self-regulating back to the asked-for RPM. But that is still but the by-product, not "religion". External goods have to do the "precision" regulation. Or not.

    And then.. per Reliance's own lab research published in a "white paper", so long as the power it needs can be supplied, the DC motor can deliver as much as NINE TIMES its nameplated torque ration at, or near "locked rotor". It cannot slip. it moves the load. Or dies trying.

    Unless the power source hits its limit ... or a protective device trips to interrupt the power, somewhere beyond 90 seconds (because they design for 90 seconds..) into "die trying" the heat in the commutator segments under the brushes expands the Copper and the segment "wedges" itself UP out of position off the back of SERIOUS thermal expansion.

    We've actually had a few - very few - photos submitted to PM that showed it had happened to one bar - high - and it's two adjacent ones- not quite as high.

    Usually, the power is NOT available for any more than around FOUR times the rating, if even that great a multiple.

    With a solid-state DC Drive, one simply sets the upper current bound for normal and permitted overload and the motor is safe.

    VFD's do the same to protect their motors, of course.

    All that said, does it matter, and if so, "when and where"?

    So long as you are primarily running carbides @ high RPM and at modest diameters on the 10EE?

    You might go for YEARS and never miss low RPM running. Because you just don't ever ask for it.

    When LOW RPM is needed? AND high Torque? AC motor? No gearbox?

    BFD.

    Just go and use the other, slower-turning lathe that DOES have low speeds.

    Easier to have two or more lathes than retain the DC motor, isn't it?

    How hard was that?


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    Quote Originally Posted by Ergo22 View Post
    Hi! I am a new owner of a 1961 monarch 10ee, got a decent deal on it out of the Midwest. it sat for about 3 years that I know of. Mechanical seems alright a little greasy but the electronics seem to be shot, found a mouses nest in the back cabinet. Chewed through wires among other things. I would like to convert to solid-state and retain most of the functions of the modular drive system. I keep reading about the parker conversion but I'm not quite sure where to begin. Other owners of this conversion any info would really help.
    It's not like you can just plug in a Parker drive (actually two drives) and go. You have a lot of wiring to do plus parts such as relays, switches, potentiometers, terminal strips, etc., to locate and procure.

    If I were you, I would consider going with a Sisso Controls solid state system. Sisso has a "module" and solid-state C16J units that directly replace a Modular-drives "module" and tubes for around $600 (link). You use your existing parts and replace wiring as needed.

    Cal

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    Quote Originally Posted by Cal Haines View Post
    It's not like you can just plug in a Parker drive (actually two drives) and go. You have a lot of wiring to do plus parts such as relays, switches, potentiometers, terminal strips, etc., to locate and procure.
    - one EStop
    - 2 toggle switches.
    - 2 10K @ 2W linear pots (I like sliders)
    - 2 double fuse holders
    - 4 fuses (semiconductor fast-blo type, per the manual for the drives)
    - one terminal strip for the boost transformer(s) (the drives have their own)
    - some wire & wire nuts. There's about a dozen or so wires. The rest is "on PCB".

    All pre-existing wire and switches come out. An SSD can duplicate the ELSR function inherently.

    Relays?

    There are relays under the hood of the motor car if you need to go for beer?



    If I were you, I would consider going with a Sisso Controls solid state system. Sisso has a "module" and solid-state C16J units that directly replace a Modular-drives "module" and tubes for around $600 (link). You use your existing parts and replace wiring as needed.
    That's cheapest.

    Also more or less identical with restoring the tubes. Just drops in Tim's goods instead of semi-unobtanium // EXPENSIVE! .... "Hollow State" that may not be in good working order due to age etc.

    Works about the same as ever.

    Don't LIKE it?

    Yah can change it LATER. Few bother. So long as it works, why bother? 10EE is just a lathe. Not a Heathkit.

    Ergo22? Go after all that dirty wiring with CRC cleaner made for that sort of cleanup and get the dirt, bug s**t, rocks, dog hair, and mouse pee out of it.

    The change in looks alone might make you realize it isn't really all that hard. Pretty sure there aren't even one hundred wires, total, in the whole machine. Even an MG has about eighty wires.

    Not as if it were a "space division" Telephone Central Office switch of the 1940's!

    ..or later..



    Telephone Central Office Frame : pics

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    Quote Originally Posted by thermite View Post
    ...
    Relays?

    There are relays under the hood of the motor car if you need to go for beer?
    ...
    https://www.parker.com/literature/SS...s/HA463296.pdf
    page 2-1: main AC contactor

    If you do what hitandmiss did, using the existing spindle control switch and speed control knob/rheostats, you need 5 relays (link).

    Cal

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    Quote Originally Posted by Cal Haines View Post
    https://www.parker.com/literature/SS...s/HA463296.pdf
    page 2-1: main AC contactor

    If you do what hitandmiss did, using the existing spindle control switch and speed control knob/rheostats, you need 5 relays (link).

    Cal
    Patient: "Doctor? It HURTS when I do ...this!"

    Doctor: "So just don't DO that!"

    A person would have to own stock in a wire & relay maker... or be homesick for an ITT Pentaconta to "do what hitandmiss did".



    Just don't use that contactor. There isn't a job for it anyway.

    Hitandmiss dragged the SSD back to "Summer of '42" - perhaps for nostalgic reasons of his own? It was a touchingly tender movie, and well acted, so good on 'im!

    But.... he's not an electron-pusher. I am. I even read the manual!

    So he didn't apply the SSD the way it was meant to be utilized.

    Don't recall if he had the 300+ VAC input, full drive-isolation, or the proper ripple filter choke, either? It NEEDS BOTH.

    This one "got it right" as to "both":

    Parker/Eurotherm 514C/507 4Q SSD DC Retrofit into 1961 10EE Modular


    User's choice if he wants to complicate the wires-nest piss out of the simple solution that came in the box from Eurotherm/Parker.

    It's a "single knob control" device, Cal.

    Single. Knob.

    Like the Joyce stick on an aircraft. Optionally with buttons for missiless, bombs, or guns. Or even trim... think Field Weakening?



    Or the one on a trackhoe that controls rotation, boom extension, bucket curl with one hand.

    Just ONE linear 10K pot delivers:

    - FWD (and how fast at it) in one half of travel.

    - OFF/BRAKE when centered. Not just "passively". Actively. It's a 4Q drive.

    - REV (and how fast at it) in the other half of travel.

    Mount that on the apron, Schaublin-joystick style. Where else? Schaublin wasn't the first. Apron-resident controls are more than a hundred and twenty years in common use, any large, long-bed lathe since they were all mechanical via rods and levers.

    Put an aircraft-style "slap down" lift-flap covered toggle for "RUN" adjacent. Those covers are cheap. And come in choice of colours. So do "Hexane" gummy-boots that fit over a toggle switch to make it oil and coolant-proof. See KB-Penta's "NEMA 4X" // IP65 housings and go buy some boots.

    Locate the E-stop wherever it makes sense. As little as five bucks will buy one.

    Done.

    That way, the entirety of the operating controls will always be in the same relative position to the operator's hand as ALREADY dances between and among the handles, handwheels, clutches, halfnuts... regardless of where the carriage is with respect to HS or TS.

    Harry Bloom did something similar, ages ago. A(ny) VFD is subject to the SAME safe-operation "ergonometrics" AKA "human factors Engineering". Not to fossilized pre-history, IOW.

    The pre-second-generation ELSR OEM control positions were not OSHA friendly anyway. Second-gen ELSR with TS-end mounted controls is "OK" for the short-bed 10EE, but only just barely. They still require taking the hands OFF the "control carriage".

    Not on my dance-card to reach around an 11 inch faceplate to get at the "motor switch" even if it DID still have the proper functionality, nor to side-reach to crank a speed control when it can be right at the hand.

    The SSD 50X was chosen for Field supply because it has signals compatibility with the SSD 514C-XX. And the 514 presents the INVERSE of many of its I/O signals on the terminal strip.

    No braking resistors required. It's a "4Q" drive. The grid is the brake.

    No relays required. No wire to what does not exist. Simpler wire to what is provided. On-PCB.

    No contactors required. No wire to what does not exist.

    No "starter" function required. It's a built-in option in onboard logic.

    Just a common rotary disconnect to interrupt the upstream with "authority".

    All on the FRONT of the machine, BTW.

    No stooping, no bending, no need of wandering around the end or back side.

    A "rotary" disconnect, for those not familiar, runs a 5MM rectangular actuating rod out the back of a shallow bezel and lock-out-tab knob. Space between those and the actual contacts us up to how long the square rod. A small hole passes it. The guts and wire can be inside a box inside the base.

    Under $30 "NOS", and lo and behold not only a NICE disconnect, but turned out to be made in the USA, not China!


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    Quote Originally Posted by rabler View Post
    The VFD conversion runs into problems with the reduction gear. Without the reduction gear it is really hard to get good performance over a wide RPM range like the original factory Monarch. You'd like good performance from roughly 20-3500 RPM.
    I assure EVERYONE, that this is total hogwash.

    As is the grand fears of complexity and troubleshooting.

    As is the comments of load compensation

    As is the doom of high cost.

    My '42 round-dial MG with flat-belt drive was probably great at one time. When I got it, the gearbox had the wonderful 'automatic belt oiler' feature. The motor mounts had rotted away, the wiring was shredded, and about half the controller contacts' points were burned away... and I had work to get done. I rewired it to 230, fitted the appropriate heater coil, and nursed it along for five years on an RPC... and in the meantime, I acquired some new old stock parts.

    best thing I ever did was gut it, clean it out, and slide in the NOS A-B 1336, the 7.5kva 480:240 transformer, and a cleaned-up/new bearings salvaged Allis-Chalmers AC motor. Three wires from motor to VFD, two wires (480v AC from VFD to transformer. Two wires from transformer (240 winding) to contactor box, two wires + ground to power supply. There's three wires from the VFD to the 10K pot (now mounted to original huge dual-resistor bracket), and three wires from VFD up to the direction switch on the headstock. Couldn't be simpler.

    Instead of gearbox and flat-belt, mine runs a 3:1 toothed belt reduction. Motor has had the cooling fan yanked, replaced with a shroud and constant-speed fan. VFD programmed to 215hz overspeed, motor wired for 460v.

    There is NO question of power... at a speed lower than I could EVER expect turn a part, it exhibits enough torque on the spindle to rip my arms right out. It'll also brake to a stop in about three rotations of a heavy chuck, or a quarter-turn with the collet... and it's basically silent. Plugs into a 240v range receptacle.

    It will spin right up to the original design indicated speed, and pin the needle on the tach, and not care one iota. My total cost (since everything was sought, and bought as 'target of opportunity', I have less than $400 in my whole conversion. I built it all up BEFORE yanking the ailing system, and I had it up and cutting in under 10 hours, most of that time was fidgeting with bracketry to support the drive and transformer.

    Keep in mind: Monarch fitted 10EE with VFDs and 5hp with gearbox, 10hp without.

    I've seen some impressive drive setups... the Ward-Leonard electromechanical VVDC drive is amazing technology, and I respect it in every application (especially traction elevator hoisting machines), but time has it's challenges, and advancing technology offers some of it's own advantages. I think the only drive system more impressive than a good-sense VFD setup, is a bona-fide closed-loop servo system... one of our sage masters here posted a video link several years ago of a servo system-driven 10EE, and it was frightening and impressive. With the advancement of such systems, good pull-outs and NOS parts come available at very low cost, and THAT is how one avoids the 'bleeding edge' price.

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    I have a fincor drive conversion on mine, it uses the factory 3hp motor. I think you can still get one of these drives, it runs on 220V and has a breaking function.
    I think it would not be hard to get one put together for a moderate cost, I have the schematics I can post it here if there is interest.
    Attached Thumbnails Attached Thumbnails image3-5-.jpg   monarch-schematic.jpg  

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    Quote Originally Posted by DaveKamp View Post
    .

    1) a cleaned-up/new bearings salvaged Allis-Chalmers AC motor.

    2) Instead of gearbox and flat-belt, mine runs a 3:1 toothed belt reduction.

    3) VFD programmed to 215hz overspeed, motor wired for 460v.

    4) It will spin right up to the original design indicated speed, and pin the needle on the tach,

    Keep in mind: Monarch fitted 10EE with VFDs and 5hp with gearbox, 10hp without.
    Neither of which matched DC performance at sane ratios and VFD Hz over-speed.
    So they went with 7.5 AC HP and went back to using the gearbox. Peter covered that many years ago, right here, Monarch forum.

    N'er mind.. not all users need full OEM power anyway, and even if they do, having better HIGH RPM regulation, and very cheaply, is generally more useful "inserted Carbides era" than uber-grunt LOW RPM and uber-stable reserves, HSS-Cobalt-Stellites era.

    So long as one doesn't have to pay too steep a price in money. Or all-around performance. ANY OEM DC motor is still present, still usable? ANY means of driving it avoid ALL the machine work, gearbox, mounts, and belt changes.

    NEW VFD and NEW DC Drives of similar quality are about the same cost.
    OLD DC drives are lower-risk. No significant capacitors to wear-out, nor age-out.

    So keeping a DC motor if you HAVE one ends up anywhere from least restoral cost, to "not TOO damned bad", even for top-end 4Q drives.

    BFD. VFD a downgrade ... or "side-grade" at best ... if you want to.

    But Dave? Your VFD plus altered ratio rig is a "one of a kind", hardly typical of what other seekers do with Vee belts so as not to have to alter the odd one on the spindle.

    With present-day hardware. And present-day costs.

    And even so, the math is puzzling me:

    1) "Flat belt" and 1942 implies a vintage where 2500 RPM was tach max. And you can peg it. OK.

    2) At a 3:1 Motor to spindle ratio step-down the motor has to hit 7500 RPM to deliver that. Most have a recommend "DNE" RPM of less? Read their data plates.

    3) 215 Hz into a nominal 1800 sync, 1750 RPM @ a common slip 4-pole motor delivers only 6450 RPM anyway. Already pushing beyond the "general case" motor's SAFE physical limits, even for a modern Inverter-Duty Marathon "Black Max".

    7500 RPM would want no less than 250 Hz for a true 1800 RPM motor, 257-260 Hz with slip under typical loading. Does that not get HOT with Iron meant for 55 Hz?

    ELSE spindle RPM would be but 2150, not 2500.

    What am I missing?

    That you meant 250 Hz, VFD max rather than 215 Hz? And there are three legs, with several orders of harmonics in the human audio range.. so does "almost silent" mean you are as deaf as I am!

    I cheat and use a Sound Pressure Level meter, of course! HAVE to do or even the crack of doom is "silent".

    Or does it mean that the Gilmer/other toothed-belt ratio is a "hunting tooth" one and not exactly 3:1?

    As said "it IS simple". The maths included.

    You'd have to know "Hot Rodders?"



    .. much the same as Monarch over-VOLT'ing, rather than over-HERZ'ing.. their DC motors! The nominal 3 HP ones provided with reserves to 4 HP or better. The nominal 5 HP's equipped for closer to 7 HP?

    Oh.. BTW .. as I value my aged arms? A common P.A. Sturtevant Torque wrench, 60 years in the IC engine side toolbox, can actually read the 10EE's torque off the spindle directly.

    So long as you limit power to the DC motor so it stays below about 5 times the nominal of around 23 lb/ft.

    PS: A Gilmer "pulley" is actually a form of gear with tolerances according, hence indexer/spacer or Dividing-head work and a "non-trivial exercise" to shop-fab. Read "pain in the a**". Also not cheap to "just buy".

    Poly/Micro Vee AKA "serpentine" by contrast are dead-easy anywhere holding "sync" is not needed.

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    I am rebuilding my second 10EE to VFD and 3 phase motor. First unit used backgear 5 hp motor and an early VFD. The machine has ran perfectly for twenty years now.

    This time around I am going 10 Hp, no backgear. Got A LOT of help on another forum to find this great motor on eBay :
    Baldor Reliance IDVSM3774T 10HP 230/460V 1760RPM Inverter Drive Motor *NIB* | eBay

    Offered $500 and total with shipping and tax is $750.

    Then got this top end VFD to drive it:
    VFD P1-00600-LFUF, AC Motor Drive

    Bought a DC choke to help out with load smoothing
    MTE DC LINK CHOKE DCA004004 40 AMPS 40A 2MH | eBay

    I still need a brake resistor and 5 Kohm pot. New pulley and belts plus a few other minor bits and pieces. Total cost all in will be about $2K.

    This system is rated to go from 3Hz to 200Hz, or 90 RPM to 6000 RPM at the motor. I plan to pulley it 2:1 so the machine will run from 45 to 3000 RPM.

    I am CERTAIN this setup will run perfectly for many years.

    I have a nice DC motor with backgear to sell, should cover a large part of the upgrade cost.

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    Quote Originally Posted by Karl_T View Post
    Then got this top end VFD to drive it:
    VFD P1-00600-LFUF, AC Motor Drive
    "Top End" major-maker VFD - for industrial use, not hobby - are priced at about triple that no-name figure, present-day.

    You aren't hurt. Just undemanding.

    A 'servo' plus a matched control amp would make more economic sense. As they now do. Straight-shunt DC has to find other work. And does. Reliance asks an MSRP of around $12,000 for a FIVE HP DC motor these days. Where they need those, they REALLY NEED those.

    A manual lathe just doesn't NEED that .... nor what CNC spindles need.

    So I run what I got. Dee Cee.

    And keep two 3 HP Reliance large-frame as spares!

    There is always some optimist pulling them out to do a VFD downgrade.

    I am happy they are happy.

    "One hand washes the other."

    Keeps the good stuff cheaper for the rest of us!

    "Go for it!"


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    Quote Originally Posted by DaveKamp View Post
    I assure EVERYONE, that this is total hogwash.
    ...
    Dave,
    So your claim is that using that reduction gear with a vfd provides no benefit? And all vfd conversions should throw out the reduction gear? And a 6:1 increase of torque at low end is not useful?

    I don’t have a test case myself. I wonder how many people with a vfd using the reduction gear feel it wasn’t worth the effort.

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    Quote Originally Posted by rabler View Post
    Dave,
    So your claim is that using that reduction gear with a vfd provides no benefit? And all vfd conversions should throw out the reduction gear? And a 6:1 increase of torque at low end is not useful?

    I don’t have a test case myself. I wonder how many people with a vfd using the reduction gear feel it wasn’t worth the effort.
    I'm with the krew in Sidney on this one. They tried it. They went back to the significant extra cost and mount-up complexity plus long-term maintenance of the gearbox vs modest upsize use of a simpler 10 HP motor NO gearbox instead of a 7.5 HP with one.

    It is not "just" about torque.

    Sometimes yah just need SLOW but stable.

    An SSD with ripple-filter can "creep" at under ONE QUARTER of one RPM. One rev in fifteen seconds.

    I don't much NEED that, but it surely makes all the other RPM bands smoother as well.
    Most especially by extending the direct-drive RPM band downward so.. ta da.. the reduction gears are less-often needed. With the 690 RPM "base" motor, anyway!

    What would an AC motor need to match that?

    Reckon we could build a scaled-up 16-pole Hunter ceiling fan that would FIT?
    Now wadda we do for the high-end?

    "Servo" it if yah need that.

    I'll stick with the "Big F*****G Ha.... err.. "velvet glove" approach, thanks!

    Dinosaurians CAN TOO toe-dance like a ballerina!


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    Quote Originally Posted by thermite View Post
    It is not "just" about torque.

    Sometimes yah just need SLOW but stable.


    Not necessarily wrong, but misleading. I'm concern that folks will think just because their lathe will turn the chuck steadily at fractional Hz using a VFD means it works good enough. A good VFD and inverter motor with some ridiculous CT range can turn a fan at a stable speed down to fractional Hz. Or turn an unloaded/very lightly loaded lathe at the same fractional Hz. But it isn't going to have any torque to really take a decent cut. On a lathe, generally slower means larger diameter (all else being equal), which is where heavy cuts are more likely, and those heavy cuts need more torque, not to mention the same cut at a larger diameter needs more torque.

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    Quote Originally Posted by Karl_T View Post

    This system is rated to go from 3Hz to 200Hz, or 90 RPM to 6000 RPM at the motor. I plan to pulley it 2:1 so the machine will run from 45 to 3000 RPM.
    Karl,that motor is rated for 6000RPM as a do not exceed speed, as in if something else is turning the shaft that the motor is connected to the motor can withstand up to 6000RPM. That doesn't mean it will produce any usable power at that speed. The motor nameplate itself says Max RPM: 4500. The data sheets on the Baldor give torque curves up to about 2600RPM (a tad under 90Hz). This means that over this speed it is going to not be able to provide rated horsepower. Here's the link to the datasheet, see pg 8. https://www.baldorvip.com/Product/In...?id=IDVSM3774T

    It is a little confusing that the datasheet drops "peak amps" down to zero at 2600 RPM, but "rated amps" are still flat at around 12A. Can anyone explain that?

    I'll be surprised if it is useful at anything more than around 120Hz. I certainly wouldn't drive it at more than nameplate MAX RPM at 150Hz.

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    RE: post #36

    thanks for your help over on the other site. Yep I am sure available power just dies when getting over 150 Hz. But the only time extreme RPMs are needed is on parts under 0.100 diameter. power needed to cut is nothing. Now it may not have the power to even make the lathe turn 3000. I'll try it and report back probably on the other site.

    Same is true at the other, low speed, end. Only time to run super slow is to thread. takes almost no power.

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    Quote Originally Posted by Karl_T View Post
    RE: post #36

    thanks for your help over on the other site.
    .
    .
    .
    ...report back probably on the other site.
    Take a guided tour around a Grand Old Castle?

    Can't stand the heat? Leave the kitchen.
    Congregate in the latest fad.. a trendy whine-bar down in the village.

    You'd have to know tourists?

    Why would the cooking staff complain?


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    Quote Originally Posted by Karl_T View Post
    RE: post #36

    Yep I am sure available power just dies when getting over 150 Hz.
    Not so. Not by that much. The torque/HP/RPM relationship is a fixed one, mathematically.

    So, too the math on Volts/Hz.


    Now it may not have the power to even make the lathe turn 3000.
    It will EASILY turn beyond 3,000.

    You might even LIKE it.


    Same is true at the other, low speed, end. Only time to run super slow is to thread. takes almost no power.
    Yah... welll.. got the patience to take enough passes, ya can thread with a "restorer" FILE..



    It isn't just "power" any more than it is "just" RPM or "Just" torque.

    It is uber-smooth stability ...under varying loading. Regardless.

    VFD does well ABOVE nameplate nominal "base" RPM.

    Really. They do. If collets and carbides are your meat? Yer good.

    And the traditionalistas may even get to scarf up the DC uber-motor you freed from bondage. What's not to like about THAT?

    Yah like to ALSO utilise HSS/Cobalt and the Stellites? Turn faceplate work and larger diameters?

    Some among us still appreciate smooth as well as powerful.. and in ALL RPM ranges, not just "some".

    Whom ever knows what the NEXT job might need? A truly "general purpose" uber-lathe as the Wizards of Sidney intended have value? Some still think so.

    Not hard.

    Pick any..... ONE.

    Or maybe just go servo yerself if yah want it ALL!


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    I'm not saying that the backgear isn't a nice thing... it provides options, and OPTIONS are always good. I'm just saying I haven't found a circumstance where I simply couldn't live without it.

    As I noted, my 10EE came with a backgear unit fitted with the "automatic belt oiling" function. The DRMO description identified the unit as "UNECONOMICAL TO REPAIR"., and the ORNL sticker said "NO LONGER RADIOACTIVE"... (that's a bonus, right?)

    Yes, Bill... MINE had a flat belt. Actually, it was closer to a 'conical' belt, by virtue of technical prowess predating my acquisition, probably somehow related to aforementioned belt-oiler, and worn out rubber suspension under the motor plate, and other stuff.

    After looking at everyone else's 10EE, I was confused by the flattie, as most I saw had matched V's.

    Yes, it's not quite 3:1, and yes, it IS set to overspeed to 250. The old Allis motor doesn't seem to care one bit... I suppose those boys knew a thing or two, learned from making the big spools at Davis Dam. I doubt my tachometer's accuracy, but I say with certainty that I have NO trust in any chuckwork at those speeds (I prefer to keep my shop safe), but I've spun it up there for small stuff in the collet.... and As others mentioned, fast work is small diameter, and there's basically zero torque needed there. The reduction of the belt takes care of the low end, and it has ample torque at the low side that I've never found a workpiece wanting more. I can see why some industrial settings might have SPEC'd it, but in my shop, if I have a workpiece that needs hogging power at 5", I take it to the pole barn and put it in the Loud and Shiplike.

    Silent... yes, there's inverter switching noise... it is no louder than the cooling fan in the motor, and about 1/6th the SPL of the running M-G I took out. I can listen to music comfortably in just about any circumstance.

    The OP asked, I put out my opinion, and my shop is open to appointments for anyone who'd like to try it, to see if it is acceptable performance for their expectations... and they're welcome to try any of the other machines I've got running on VFDs, or my welders, too... and visitors are welcome to even try out the contents of the beverage fridge, as long as you don't get too deep into my wife's beer... she's a bit ornery about her Spotted Cow and Summer Shandy.


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