Renovating a Hardinge HLV-H

I mounted the DRO on the front of the bed.

I had to make a bracket to attach the scale to the apron. I didn't want to drill any more holes in the machine, so I devised a mount that would fix to one existing apron bolt and then clamp to the bottom edge.


I'm fairly pleased with the result; The rear clamp grub-screws area real pain to tighten, but once done-up the bracket is very secure.

Getting the armoured cable to roll with the movement of the carriage without getting snagged on the edge of the sump was a tedious job - In the end I had to add a perforated cable guide under the edge of the bed and a length of spring wire to the cable to keep it straight. I should be ok

A bit premature perhaps but, I thought I'd fit the doors

Applied power to the thing for the first time.

First I rewired the control transformer to accept 240v input (instead of 440) then checked the contactors were operating OK.

Checked the power feed controls - they were working OK, except I'd reversed the connections to the variable transformer so high speed was low and vice-versa (easily fixed).

I then bodged* my 440v VFD on, temporarily using the control transformer as a step-up. Got the spindle spining in both high and low speed and up & down the speed range.

But, while doing all this, I noticed the slow-start resister on the VFD was smoking (It's an old 5HP Toshiba device and has a softstart to prevent fuses popping on switch on). I powered down to investigate why the relay, which bypasses the resister, was not working. I had to take the VFD apart to find out why (I have no manual for this thing). I stuck it back together only to get no responce at all. I then realised I'd forgotten to replace the current limit lead (which has to be removed to get at the relay).

It popped a 600v 20A fuse and killed one of the IGBT modules :(
( a MG50M2CK1, if you have any in your pockets)

BTW Mike:

I found a couple of subtle differences between my machine and the wiring diagram from your site:

The spindle interlock contactor is wired in a different place it disconnects the 3ph only to the motor and the 1ph control power to the up/down contactors

A couple of spare contacts on the fwd/reverse switch are used to break the main contactor coil circuit - so if the fwd/rev switch is changed while running it stops the machine.

I'll draw a diagram of it for your site if you wish.


*(I do this sort of thing for a living, so by bodged, I do not mean unsafe)

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Originally Posted by BillTodd

BTW Mike:
I found a couple of subtle differences between my machine and the wiring diagram from your site.
I'll draw a diagram of it for your site if you wish.

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I'm not surprised. That's one of the reasons that they have a pocket in the electrical door - to hold the as-built condition of the machine when it went out the door of the factory. That condition does change over time, usually in minor ways. I've also noticed occasional cultural differences in wiring design between the US and European models, mostly related to safety practices on each side of the pond.

I'd be delighted to put it up on the aafradio site as another variation if you'd like to e-mail it to me. Never can tell who it might help in the future.

I had to finish the worklight before I could post these :)


Progress has slowed while I'm awaiting the 240-415v step-up transformer to arrive from Airlink Transformers. Meanwhile, I've found another, much smaller and neater, Variable Frequency Drive to power the main motor ( A 1500W Siemans MM150).

I'm bidding on a couple of low power (100W) VFDs to run the coolant pump and speed change motors at the moment, with the intention to completely rewire the control box.

The plan is to use the interlocked pair of contactors (currently used to control the speed adjust motor) as a new speed selector relay. This new relay pair will only change speed (thus disconnecting the VFD) when the VFD is stopped. I'll keep the original speed change lever and switch, but it will be used at 24v to control the VFD.

I could use a microprocessor to control all this but, at the risk of being called a luddite, I intend to use simple relays in the interest of fixability (by others).

I'll post a circuit when I've worked out the details.

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Originally Posted by BillTodd

I had to finish the worklight before I could post these :)

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What a difference a day makes... (with apologies to Dinah Washington...)

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Originally Posted by BillTodd

I'm bidding on a couple of low power (100W) VFDs to run the coolant pump and speed change motors at the moment, with the intention to completely rewire the control box.

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Actually, the spindle motor VFD will also run the small motors quite well without complaint, Bill. I don't know how you intend to use your VFD, but I use mine 99% of the time to generate 60Hz (50 Hz in your case.) The remaining 1% is for a virtual backgear for slow threading or large faceplate work in stainless or other tough steels at 25-30Hz. That big super balanced motor is on a 5 hp frame and won't take overspeeding lightly.

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Originally Posted by BillTodd

The plan is to use the interlocked pair of contactors (currently used to control the speed adjust motor) as a new speed selector relay. This new relay pair will only change speed (thus disconnecting the VFD) when the VFD is stopped.

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I may have misunderstood the logic you described, but I believe I might rethink that approach. You absolutely want the ability to raise or lower spindle speed while the tool tip is cutting! I can't count the number of times just a small change in speed has stopped tool system resonance (skreeeeech) and resulting finish problems when turning a part or threading. I wouldn't give up that unique capability that Hardinge designed into the lathe for a thousand bucks.

Here's a suggestion - just bypass the control transformer (feeding it from straight 415v), and hook up the VFD feeding everything else and give it a try. You won't have to change anything that way except the wires to the control transformer. Leave the high/low speed lever in the position you will use most of the time. Use a separate on/off pushbutton for the VFD like this one:
http://aafradio.org/garajmahal/Hardinge_PB.jpg
Try it...you'll like it...:beer:

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I may have misunderstood the logic...

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No, it's my fault for not making it clear :)

For those unfamiliar with the Hardinge drive train; The lathe has a dual speed (480/1480 rpm - 0.5/1.5hp) three phase drive motor and a 8:1 variable V-belt system (driven by a motorised jack with up/down buttons - see attached picture) that gives it two ranges of 125 to 1000 and 375 to 3000rpm.

The dual speed motor is controlled directly by a lever switch giving Low/Stop/High speeds. The motor is sufficiently robust to withstand the current surges caused by abrupt speed changes when connected to a three phase supply. (i.e. it is possible to switch high>Low or Low>High without stopping)

I'm going to drive my main motor from a 1.5kW electronic variable frequency drive (often called an inverter or a VFD). These convert the single phase mains to a variable frequency three phase. They can ramp the motor speed up and down, slow it quickly with DC injection braking and all sorts of clever tricks.

I want to keep and use the Hardinge Low/Stop/High Lever control. However, the VFD will not take kindly to the power surges if I leave it connected as it it now - it will just stop with a fault code or worse, go bang.


I will switch the motor connections to the VFD with a dual contactor (one for high one for low), changing the range only when the VFD says it is at 0Hz (stopped). These contactors have to be a mechanically interlocked pair to ensure that both cannot be 'ON' at the same time. These are a fairly expensive and awkward to find item . Fortunately, there is already a pair of these in the control box, used to control the variable speed jack. I'll use another small (100W) VFD to drive the jack up and down.

The main VFD has enough power to drive both the jack and the main motor. However, using a separate VFD for the jack means I can also dispence with the fwd/rev contactor allowing the main VFD to reverse without upsetting the jack motion.

I'll make a simple control circuit* (it only needs to be two small relays) that will take the input from the existing lever switch. If/when the lever is moved directly from one speed to another it will; tell the VFD to STOP, and once the VFD says it is at 0Hz (stopped) it will change the range contactors then tell the VFD to ramp back up to speed (50Hz).

I wont be using the VFD to change the motor speed, it'll simply start,stop and reverse it smoothly [although, as you say Mike, using it as an electronic back gear might be useful]


*I cut my teeth on a microprocessor controlled motion sensing logic for a 24trk tape recorder, but I don't want it to make this that complicated.
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Yesterday I tested the new VFD. Typically, after searching everywhere to find a cheap step-up tranformer and ordering a new one (80 sobs! :(), I remembered I had a 1kVA tranformer that would do the job perfectly !!! (Kip, of this parish, will be laughing at this point because I sold him the other one of the pair I had)

It took about a hour of playing with the up/down speeds, adjusting the brake, oiling the pulleys etc. to get the lathe to run smoothly. The attached picture shows a penny balanced on the head stock while the spindle is spinning at 3174rpm, unfortunately the camera flash has frozen the motion.

Mike,

Here's the original wiring diagram in PDF format (hope it's not too big for your site).

Bill

[edit] pdf updated - spindle interlock corrected

Great work Bill, I jumped over here to see your work after reading your posting on the PM site about your vibrating collet closer. I can't believe how well you got the rusty steel components to "clean up".

I love Hardinge lathes. I have (2) HLV-H's, (1) HLV-TFB, & (2) HC's. I also have the Feeler clone of the HLV-H:). It's a disease I tell ya!

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Great work Bill, I jumped over here to see your work after reading your posting on the PM site about your vibrating collet closer.

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Thanks Jim :) (I'll pick up the collet closer thread on PM)

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I can't believe how well you got the rusty steel components to "clean up".

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I think I'm lucky it was so cover in filth (congealed coolant) is has to a large extent protected the steel from the weather.

The step up transformer arrived this morning (early - someone forgot to put the clocks forward?) .

I spent a few hours playing with the VFD, checking and testing how the various function would work when connected to the motor. Last night I had worked out a scheme that would allow the speed to be changed without slowing to a stop first (making the VFD 'catch' the spinning motor) ; It worked fine going from fast to slow, but wasn't at all happy the other way around :(

One irritation, the 0Hz (stopped) output function doesn't work as described in the manual - bizarrely, the relay contacts open (instead of close) to indicate the VFD has stopped driving the motor :confused: It's not a show stopper, but after I had pared down the control circuit to just one relay, it's annoying to have to add extra circuitry to work around it.

[edit] BTW I won the two 100W VFD I need to finish the control box. When they arrive I'll strip out the old panel and start rewiring.
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'I have a lathe that is basically running - what should I do now?'

Cut a thread!

I had to make a new M12 T nut to mount the little QCTP from my Southbend onto the Hardinge compound and find a spacer to bring it up the the correct height.

Turned and faced a piece of 16mm steel stock - First attempt at a 1/2" thread was a bit of a disaster; got the stop in the wrong place , disconnected the halfnuts to reposition it and, of course, b*****red the thread.

Turned it down to 3/8" - BTW if you haven't got a DRO on your lathe, get one. It makes turning things to size a doddle (it doesn't need to read down to 0.00005" :p). - got the threading stop almost in the right place... and Wow! now I see why HLV's have a reputation for easy threading.

So now I have a 3/8" 26tpi thread on the end of a bar :) Yes I know it's an odd thread ; it was supposed to be 24TPI but I had a parallax problem with the gear selector (Hardinge owners will know what I mean - I should have counted the holes instead of looking at the number on the plate :LOL:)

I have cut some beautiful threads that were the wrong pitch. When counting holes don't forget the first one is a "parking" spot, that doesn't have any gear engagement.

Mike - I've just updated the wiring diagram

http://www.mycncuk.com/forums/showpo...0&postcount=49

Here's the first draft of the new control circuit. I have avoided as much 'electronics' as possible (even to the point of using a relay as an inverter) to keep it as a set of simple black boxes.

It works as follows:

By default it powers on to the low speed setting with the Speed Select Relay's nc output engaging the 2ML contactor connecting the low speed windings to the VFD.

If the Speed Change Lever is moved left to the Slow position. A RUN signal is supplied to the VFD via the Speed Select relay and R1/C1 (more on these later). The VFD's 0Hz contact will close, switching the output of the Inverter relay to open. The VFD will ramp up the motor to full speed 480rpm (50Hz) in a few seconds.

Now If the Speed Change Lever is moved right to the Fast position. The Speed Select relay's no output is open so the RUN signal drops to OFF and the VFD ramps down to 0Hz (Stopped). When it reaches 0Hz the VFD's output contacts open forcing the Inverter relay's output to 24v. The 24v 0hz signal is used to change and latch the Speed Select relay to High speed. As the relay changes speed, R2 is taken to 24v, charging C2 in about a hundred milliseconds (to give time for the contactors to settle) and generating a new RUN signal to the VFD. (R4 discharges C1 via R1 ready for the next speed change)


If the Speed Change lever is then switched back to the Slow position, when the 24v 0Hz signal is generated, it is applied to R3 which disables the Speed Select relay's coil so switching it back to Slow.

If the Speed Change lever is centred (STOP) then the RUN signal is removed and the brake is applied. The previously selected speed is retained by the Speed Select relay.

Looks good, My HLV is # 461 and thought it would be while before I saw an older one. I was too looking at swapping out to an Inverter, at the minute, I have it rigged so that the ctrl is supplied direct of 240 mains, (bypassing the transformer) and I engage the slow or high run relay’s before I tell the inverter to ramp up. (Not ideal – but ok temporary) I might inquire as to how Cyclematic lathes do their speed control. Do we know how the new Hardinges work ? – be good to see a new Schematic and even more interesting would be the New HLV that has just come out, with the servo leadscrew. In my case I have only just ripped out and restored the wiring to original and everything works fine so I may try to keep it original. Quick question,, with regards to the brake, you are still retaining the mechanical brake solenoid. This is the way I would be doing it, but thinking about it there may be some merit in using the inverter to do the braking, what are your thoughts on that? The auto transformer you are using is single phase, are you doing the same as me and feeding the inverter with 400V single phase ? and not running it at full capacity ? I should really get some pictures of mine on this forum.... I have just got to the primer & paint stage, (lotts of dammage to my carrige gears + rebuilding the carrige feed motor + revising its electronics have taken a lot of time) Best Jon P

Hi Jonathan,

Good to hear from you:)

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.. be good to see a new Schematic and even more interesting would be the New HLV that has just come out, with the servo leadscrew.

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Yes it'd be nice to know if the lever still directly controls the speed change or weather they are just using a single speed motor and a clever VFD. (I suppose it would even be possible to design a dual output VFD just for dual speed motors)

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Quick question,, with regards to the brake, you are still retaining the mechanical brake solenoid. This is the way I would be doing it, but thinking about it there may be some merit in using the inverter to do the braking, what are your thoughts on that?

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I'm retaining the mechanical brake as it is useful for collet changes etc.. ATM it will only operate when the lever is in the STOP position (or when the spindle lock is ON). During ramp down for speed changes, the VFD does all the braking. Incidently, I found the VFD slowed the machine faster, without faulting, using the ramp down without dc injection.

It's a real pity that my VFD's 'catch spinning motor' routine doesn't seem to work 'as advertised'. If it is has to speed-up the motor (i.e. when changing from low to high speed) the motor complains loudly. The high to low speed transition was flawless. (I guess it ramps down from max frequency ).

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The auto transformer you are using is single phase, are you doing the same as me and feeding the inverter with 400V single phase ? and not running it at full capacity ?

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The Siemans VFDs are rated at full power while working on single phase (many [most?] that will run on single phase will not need to be derated - it's only losing two diodes in the bridge rectifier, if the remaining four will take the extra current there's no need to de-rate the VFD)

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I should really get some pictures of mine on this forum.... I have just got to the primer & paint stage, (lotts of dammage to my carrige gears + rebuilding the carrige feed motor + revising its electronics have taken a lot of time) Best Jon P

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Yes do post here I'd love to see it.

I'd be tempted to replace the DC motor with a smaller 3ph one and use another small VFD for power feed - It'd have a much better speed control

Sorry to here about your carriage gears. Are new ones very expensive? :(

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Originally Posted by BillTodd

It's a real pity that my VFD's 'catch spinning motor' routine doesn't seem to work 'as advertised'. If it is has to speed-up the motor (i.e. when changing from low to high speed) the motor complains loudly.

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You might consider changing the sampling frequency as an experiment. If the motor is emitting higher frequency noises, it's often a function of mechanical resonance of the windings under load.

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Originally Posted by BillTodd

The Siemans VFDs are rated at full power while working on single phase (many [most?] that will run on single phase will not need to be derated - it's only losing two diodes in the bridge rectifier, if the remaining four will take the extra current there's no need to de-rate the VFD)

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The size of the filter capacitor on the DC bus actually has more to do with derating than the size of the diodes, though of course the diode rating has to be considered for single phase feeding of a larger capacitor bank. Most of the VFD's I've seen suggest a 1/3 derating...e.g., use a 3hp rated unit for a 2hp motor. That's consistent with the energy under the power curve for three phase versus single phase rectifier designs. The VFDs that are rated for single phase simply have a larger capacitor bank in them. If the supplied voltage from a three phase input design VFD sinks under a heavy cutting load, it is usually fairly easy to add capacitance to the unit externally to solve the problem. The risk is exceeding the current rating of the internal diodes because they are charging a heavier peak load in each cycle. It's usually not a problem for reasonable (<50%) increases in capacitance, but needs to be checked.

Hi Mike, Did you download the '61 wiring diagram OK (not too big in pdf form)?

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You might consider changing the sampling frequency as an experiment. If the motor is emitting higher frequency noises, it's often a function of mechanical resonance of the windings under load.

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Yeah, I fiddled with a number of things (I'm currently running it at 16kHz 'cos the motor's lightly loaded and it makes it silent).

The 'catch flying motor' function is odd; it should have no difficulty re-syncing to a slower motor. However, it says in the spec that it auto-senses the number of poles on the motor, it's unclear if this is only happens when RUN is selected. If it only senses after RUN then that might explain why it wont sync to the motor.

After playing around with it some more today, I'm sorely tempted to add a microcontroller to the VFD's serial bus, just so I could adjust the drive parameters 'on the fly'. I'm sure it would be possible then to dispense with the speed change relays and just tell the VFD to STOP (cut the power) prior to a speed change and pick up at the correct frequency after.

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The size of the filter capacitor on the DC bus actually has more to do with derating than the size of the diodes

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I thought someone would pick-up on that :)

I've just re-checked the Siemens' data, there no de-rating for single phase operation. although it does suggest the large power ones may need an external choke.

Interestingly, the box has terminals with access to the HV DC supply, but the manual doesn't show them. However, In an earlier model manual I downloaded, it did show them and DC brake resistor terminals. I wonder if smaller modern capacitors allow Siemens to 'over-rate' the filter for 3ph?

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Originally Posted by BillTodd

Hi Mike, Did you download the '61 wiring diagram OK (not too big in pdf form)?

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I sure did. Many thanks for the effort!

Lessee...I got three e-mails in the batch this morning that had attachments greater than 75MB, so, no, it wasn't too big...:p

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After playing around with it some more today, I'm sorely tempted to add a microcontroller to the VFD's serial bus, just so I could adjust the drive parameters 'on the fly'. I'm sure it would be possible then to dispense with the speed change relays and just tell the VFD to STOP (cut the power) prior to a speed change and pick up at the correct frequency after.

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Sounds like an interesting project. After 40 years of battling customers to define requirements for a few zillion projects, I'm moved to curiosity over why one would need the capability to switch from low to high or high to low quickly while it is running -at least on a manual lathe - but as long as you're having fun...
:beer:

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I've just re-checked the Siemens' data, there no de-rating for single phase operation. although it does suggest the large power ones may need an external choke.

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The elimination of derating seems fairly common in one horsepower and less units. I suspect it has mostly to do with the low cost of capacitors and the re-use of the circuit boards in the 20HP and lower lineup.

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Interestingly, the box has terminals with access to the HV DC supply, but the manual doesn't show them. However, In an earlier model manual I downloaded, it did show them and DC brake resistor terminals. I wonder if smaller modern capacitors allow Siemens to 'over-rate' the filter for 3ph?

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Of all the VFDs I've examined, all but one had easily accessible DC bus connections. The capacitor choice was likely made using a trade-off study of the cost of buying large quantities of one size versus smaller quantities of various sizes. That usually brings out the head scratching in those of us who buy the older stuff. :rolleyes:

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Sounds like an interesting project. After 40 years of battling customers to define requirements for a few zillion projects, I'm moved to curiosity over why one would need the capability to switch from low to high or high to low quickly while it is running -at least on a manual lathe - but as long as you're having fun...

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It has more to do with keeping the speed control lever as a go/stop device, than the need to switch speed.

I like the clunky lever. It reminds me of a time before 'Health and Safety', before every thing had to have an E-Stop button. A time when Window-cleaners were allowed to use ladders (you may be surprised to learn that EU/UK law now forbids them to use ladders!!!!!) A time when, when things 'go wrong' it was not always someone else's fault.

I will have my lever - even if it takes 100k LOCs (of machine code) :)

Well, that's sorta what I assumed, but my knee-flex reaction training always kicks in...heh, heh... :D

I always liked the lever action too, but one day a workpiece that was enduring a nasty interrupted cut because of its odd shape didn't think it was restrained well enough and escaped just past my ear at about the speed of sound. :rolleyes: Ever since then I tend to stand over to the right of the potential workpiece ejecta path, which is why the VFD control is there on my lathe in the photo above.... How many LOCs to guard against that?:confused:

I'm just teasin' you, Bill. When I was younger I spent a lot of time designing stuff like that for the shop simply because it was fun to do. "Because it's there" is a perfectly good rationale for doing it at times. And I agree with your observation about personnel safety regulations in Western countries. I suspect that the end result will be working uniforms that look like the Michelin Man and padded rooms to prevent us from hurting ourselves if we stumble into a wall. Wait! That sounds like an insane asylum!

Just fitted the rewired control panel. :)

The control logic is just a bird's nest ATM while I test it, but it seems to work as advertised.

The photo shows the bird-nest logic and temporary 24v PSU (bottom right) I'll knock up a PCB for the two relays and PSU. I'll add a low voltage (50vac) transformer to power the work light and use (half) to power the logic.

All I have to do now is convert the speed adjust motor to 240v...

Looking very Nice indeed.

once i have finished mine, i will be doing the same type of thing.
Good work !!


Jon

I don't know what convinced me that the speed jack motor was dual voltage (I thought it would be American, but it was made in Swansea) but, it ain't, and there's no easy way to convert it (I was prepared to carve into the insulation to find the star point but thought better of it when I saw it close up)

So, while plan B is gestating, I've implemented plan C and fitted a couple of contactors (one does the reversing, one connects the motor) to drive the Jack from the main VFD. (Stop laughing - Mike :))

While I was in the engine room playing with jack, I noticed a nick in my motor belt. I've just got of the phone with Ken at ZMT (Hi Ken) to enquire about a new one, so another £80 will be departing from my bank account soon.

Ken was also convinced that all the speed jack motors were dual voltage, which made me feel a little better.

http://www.youtube.com/watch?v=rLXg0... motor control

Do I really sound like that???

Really good,
have you played with the acceleration + deceleration and found those to be the best match for kindness to the machine vs speed of use. ?

how have you got over the mechanical brake fighting the programmed ramp down time ?

good progress i will post some pictures of mine soon (promise)

Jon:p

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Originally Posted by Jonathan P

Really good,
have you played with the acceleration + deceleration and found those to be the best match for kindness to the machine vs speed of use. ?

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Acceleration/deceleration times are determined by that required at max speed (which is a pain) Too short and the VFD will trip with an over-current or over-voltage fault. I may look into an external brake resistor for the VFD which should fix the over voltage problem.

I'm having to fight the idea of adding a micro to command the VFD; For a little extra work I could dynamically alter the VFD settings to match the lathe's speed. But, the relays work, so perhaps I'll just live with it the way it is.

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how have you got over the mechanical brake fighting the programmed ramp down time ?

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I haven't ATM (although, the brake is only applied when the lever is in the stop position) I could easily take a feed from the 0Hz relay and apply the brake only when the motor is at rest (but corks are cheap, so WTH)

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good progress i will post some pictures of mine soon (promise)

Jon:p

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I'm waiting :rolleyes:

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Originally Posted by BillTodd

So, while plan B is gestating, I've implemented plan C and fitted a couple of contactors (one does the reversing, one connects the motor) to drive the Jack from the main VFD. (Stop laughing - Mike :))

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Heh, heh...not laughing, just enjoying the innovative workarounds. Whatever does the job is good...and it works very well, judging by the YouTube page.

I am sorta wondering how long you can resist starting to make chips, though... :rolleyes: The temptation would be overwhelming to me.

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I am sorta wondering how long you can resist starting to make chips, though

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The 'newness' hasn't worn off yet,I don't want to get it dirty. ;)

Try breathing into a paper sack until the feeling passes...:beer:

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Originally Posted by aafradio

Try breathing into a paper sack until the feeling passes...:beer:

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Rolls On Floor Laughing :)

I'm just waiting for you to mention the moment of amazement and exhilaration when you move the cross feed dial .0150" in 303 stainless and find the work has reduced in diameter by .0150". :rolleyes:

For a 45 year old lathe, that's better than looking at a new paint job any day!

Of course, I was brought up on a 1942 South Bend Heavy 10, where any relationship between the dial settings and diameter reduction in multiple materials was a complex variable that could be analyzed only through advanced calculus...:D

Updated Circuit diagrams.

Not much to photograph ATM, but...

I fitted a 4 jaw chuck (so I can make a backplate for a 3jc) which exacerbated the braking time problem; Essentially, the braking time for all speeds is determined by the time it takes from the highest speed, with the extra flying mass of the chuck I had to extend the brake time - I don't mind a ~6 second stop from 3000rpm, but the same from 125rpm is silly.

I emailed Siemens for advice on adding a braking resistor, to allow the VFD to brake harder, unfortunately my model VFD does not have the brake transistor fitted, so I can't do that. They were kind enough to suggest an alternative; an MM440 (@ £467), Keypad (£28), Brake resistor (£112 - expensive, even for a big resistor, I think) and a class A filter (£61). I thanked them for their help, but I won't be going down that road.

This morning I found, buried in among the 'JOG' parameters, in the Siemens VFD is an option to use the jog up/down ramp times instead of the normal ones; switching between the two settings with one of the digital inputs. A quick re-wire and now I have ~2s stop times from low speed and ~6.5s from High speed with chuck :)

It makes the whole lathe feel better. (must redo the youtube video)

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Originally Posted by aafradio

I'm just waiting for you to mention the moment of amazement and exhilaration when you move the cross feed dial .0150" in 303 stainless and find the work has reduced in diameter by .0150". :rolleyes:

For a 45 year old lathe, that's better than looking at a new paint job any day!

Of course, I was brought up on a 1942 South Bend Heavy 10, where any relationship between the dial settings and diameter reduction in multiple materials was a complex variable that could be analyzed only through advanced calculus...:D

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I am blown away by the finish I can get on ally - without even trying.

A while ago, I made a fly cutter for my drill/mill from a ~3/4" stainless-steel bolt on my '37 SB 415 (9") it struggled (as you can imagine a SS bolt is very hard) but it chewed enough off to do the job. The finish was awful

In a bored moment I dialled it into the HLV chuck and took it down to 14.000mm with a couple of passes :) BIG CHEESY GRIN

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Hello aafradio it appears that you have not posted on our forums in days !
Why not take a few moments to ask a question, help provide a solution or just engage in a conversation with other members.
Great things can come from the smallest of things !

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My goodness, I had no idea the forum requirements had such a high standard!

In the spirit of the message: Bill, have you altered the spectrum of your voice in the YouTube video with a synthesizer yet? I recommend using the spectrum distribution associated with James Earl Jones' voice in the Star Wars series. Very effective....:rolleyes:

(I think I have satisfied the unseen voices now...)

Quote:

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In the spirit of the message: Bill, have you altered the spectrum of your voice in the YouTube video with a synthesizer yet? I recommend using the spectrum distribution associated with James Earl Jones' voice in the Star Wars series. Very effective....

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Odd thing, but to me, I sound just like JEJ (or Richard Burton) so it must be the microphone that makes me sound like a country bumkin ;)

I've pretty much finished the renovation now. I've just fitted the machine with castors so I can move it around the workshop until it fits somewhere.

The castors are just about man enough for the job, they'll allow me to get behind the machine and access the electrical box easily. I'll have to chock the machine with wedges once in position.

My brother gave me a nice little 80mm german(?) made chuck, so the first real job I used the lathe on was a chuck mount for the taper nose - I'll have to make myself a better boring bar though, I couldn't stop the little one I have squeaking and chattering.

Finally got 'round to replacing the bird's nested control circuit with a proper PCB

Wow bill that is some wiring mate, shop is looking good to great job and all the best in the future machining. How soon do you hope to start turning your first part ?