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Bill McLeod
09-10-2012, 10:11 AM
I just bought this mill and it has a 1.5 Hp 575 volt motor. My shop has only 240 1& 3 phase so I am looking at getting a transformer. I am also considering getting a different motor with more HP and if that happens I would get 240 volt. I don't want to waste money on a transformer if I would be better off getting more HP right off the get go. I am looking for comments from anybody who has or has used this mill relating to HP and comments on the mill in general are welcome. My understanding is that 3/4 of these mills were manufactured with the 1.5 Hp but later on they changed to 2 Hp, I am thinking of 2 or greater, possibly a 5Hp. Your comments are welcome.
Bill

lazlo
09-10-2012, 10:34 AM
I love my 602 -- I think it's one of the finest turret mills made. I've got a 2 HP motor (I thought that was the factory default?), and have never bogged it down.

MaxHeadRoom
09-10-2012, 11:32 AM
The ones I picked up have a 220v/460v 2hp and 1.5hp GE Pancake motor, I have a 1.5hp used spare motor.
I also fitted a 240v VFD and changed the (Noisy) Vari-speed to direct timing belt drive, and use the gear box for the lower range, I run the 4 pole motor up to 120Hz.
Max.

Mcgyver
09-10-2012, 01:21 PM
mines 1.5 hp, and one of the early ones (heavier castings) .....I'm not sure how muchmore than 1.5 hp its capable of taking. If you want a 5hp mill, get a horizontal :D

Can you get a motor with that form factor? I'd doubt it, but maybe....if not I'd go the transformer route or get the motor rewound (new bearings and rewind should slightly less than a new motor)

The VFD is convenient, quiet is good and it allows for the type or replacement Max did. However the varispeed in my experience/knowledge is reliable and its better to reduce mechanically....so if its there and working there's value in keeping it

Harvey Melvin Richards
09-10-2012, 01:23 PM
I love my 602 -- I think it's one of the finest turret mills made. I've got a 2 HP motor (I thought that was the factory default?), and have never bogged it down.
Why do you say this? I have one at work, I'm not sure what model, but it's always been the #2 mill. Mine has a rather low bed height 36" to 38", which I really hate.

wierdscience
09-10-2012, 02:54 PM
Easiest way is to replace the motor. A NEMA 184TC frame motor is usually the easiest to retrofit,IIRC the Excello motors have a fairly short shaft as VS mill motors go.

If you want to do an upgrade converting to a single belt drive and a VFD is the way to go.You can then add a spindle Tach like the Taculator and have all the bells and whistles.

http://littlemachineshop.com/products/product_view.php?ProductID=2658&category=

MaxHeadRoom
09-10-2012, 03:10 PM
Or with a VFD, there is often 2 configurable analogue outputs that will drive a moving coil meter for RPM indication.
Max.

Mcgyver
09-10-2012, 03:47 PM
If you want to do an upgrade converting to a single belt drive and a VFD is the way to go.]

how is the VFD an upgrade? You already have variable speed and you take it on the chin on the torque. I can see it if the varispeed is shot...but otherwise..???

MaxHeadRoom
09-10-2012, 04:00 PM
On the manual version I guess it is moot, but on the CNC version it is nice to program by S value.
Even manual just turn the Pot!.
Incidentally on this model, Excello recommended going to A.T. Fluid for the gear box.
Max.

Mcgyver
09-10-2012, 04:07 PM
imo its far from moot. at say 600 rpm low range at call it x amount of torque. I want to go down to 100 rpm. With a VFD I have x torque @ 100 rpm. With mechanical reduction I have 6x torque & 100 rpm, correct?

Now a particular person could say I never need low torque or 1/6 is enough for me or I had no choice because the varispeed was pooched which is a fair good...but afaik its clear there is a massive penalty to pay in torque in going with a VFD vs the machine's original mechanical set up

MaxHeadRoom
09-10-2012, 04:34 PM
But Like I said previously, I use the 6 (something) to 1 gear box for the low range, I have never stalled or had a problem yet?
It is only the vari-speed I have removed, not the gear box?
Max.

lazlo
09-10-2012, 05:04 PM
mines 1.5 hp, and one of the early ones (heavier castings) .....

FYI, I have one of the last 602's made, and it's quite a bit heavier than the earlier models. Especially the knee. In fact, the knee is so massive that you *really* have to have power feed.


how is the VFD an upgrade? You already have variable speed and you take it on the chin on the torque. I can see it if the varispeed is shot...but otherwise..???

The Reeve's drive on the 602 is especially loud. It sounds like a cement mixer (and mine was practically new when I bought it). One of these days, I'm going to do the VFD conversion...

Mcgyver
09-10-2012, 05:10 PM
But Like I said previously, I use the 6 (something) to 1 gear box for the low range, I have never stalled or had a problem yet?
It is only the vari-speed I have removed, not the gear box?
Max.

which is fine, works for you...and I'm not saying you're doing anything wrong or criticizing.

but....at the bottom of either high or low range you get 1/6 the torque:


at say 600 rpm low range at call it x amount of torque. I want to go down to 100 rpm. With a VFD I have x torque @ 100 rpm. With mechanical reduction I have 6x torque & 100 rpm, correct?

Whether you are in high or low range, at the bottom of that range you will be getting a fraction of the torque you'd get via mechanical gearing down

Mcgyver
09-10-2012, 05:16 PM
FYI, I have one of the last 602's made, and it's quite a bit heavier than the earlier models. Especially the knee. In fact, the knee is so massive that you *really* have to have power feed.
..

I suspect that, anticipating this moment, they custom made yours :D


The Reeve's drive on the 602 is especially loud. It sounds like a cement mixer (and mine was practically new when I bought it). One of these days, I'm going to do the VFD conversion.

quiet is nice, but not at that sort of performance degradation - for me. then again i don't know how noisy yours is or to what use you put it. Whether ones cares about the degradation is a matter of individual circumstance, but Bill, who started this, should be aware of it. Personally I wouldn't want to lose the torque and mines not noisy, at any more than any other machine.

MaxHeadRoom
09-10-2012, 05:24 PM
The only thing I can say is I have used some fairly large dia indexable end mills without any sign of stall or other effects?
So far it is working for me.
Lazlo: Mine have the motor operated ball screw Knee jack which is pneumatically counter balanced.
Max.

lazlo
09-10-2012, 06:41 PM
Lazlo: Mine have the motor operated ball screw Knee jack which is pneumatically counter balanced.

Nice! I saw that in the Excello catalog and was jealous :)

lazlo
09-10-2012, 06:46 PM
I suspect that, anticipating this moment, they custom made yours :D

I've seen all four versions in the flesh, and the final version with the massive knee is 2,800 lbs. The earlier models with the round table endcaps are quite a bit lighter: 2,400 lbs.


quiet is nice, but not at that sort of performance degradation
...
mines not noisy, at any more than any other machine.

No performance degradation, it's just noisy, like any Reeve's drive. Then again, Monarch guys with the Motor-Generator will claim it's quiet, but that sounds like a washing machine :)

wierdscience
09-10-2012, 09:03 PM
how is the VFD an upgrade? You already have variable speed and you take it on the chin on the torque. I can see it if the varispeed is shot...but otherwise..???

Reeves drives aren't very efficient,a 1hp step pulley drive B-port will put the same torque to the spindle as a 2hp Reeves VS head.The VS heads are also noisy as Robert mentioned and cost a few bucks to fix when they break.

In a motor swap a 3hp C-face motor will cost less than half of a direct fit motor $325 vs $800.That leaves money for the VFD.

When installing the VFD the Reeves pulley on the motor goes away as does the movable half of the front pulley.A simple V-belt drive replacing it.With the lo/hi gearbox still in use the new drive will do everything the old one did and a good bit more.

Dividends are paid by having better surface finishes,more precise speed control and the machine can,assuming healthy spindle bearings be spun up to the original max rpm and beyond without sounding like it's about to explode.

The OP mentioned his motor was 575v only which means no rewind and no reconnect for lower voltage,so basically he has no motor.

Bill McLeod
09-10-2012, 09:41 PM
well that gives me lots to think about, any recommendations on VFD for this application?? and don't hesitate to recommend a seller. Having worked in shops my whole life I hate machines that make more noise than needed so I am leaning towards what wierdscience has said. The main thing is i don't want to drop $600 on a transformer and find out I went the wrong way. At least with you guys giving input I stand a chance of getting it right,,,, better than shooting in the dark.
Thanks

Mcgyver
09-10-2012, 10:05 PM
Reeves drives aren't very efficient, a 1hp step pulley drive B-port will put the same torque to the spindle as a 2hp Reeves VS head..


I claim no expertise in this subject of Reeve efficiency, but here's an old post of Forrest's claiming 85-90% efficiency.

http://bbs.homeshopmachinist.net/threads/12984-Variable-Speed-Drives

Whatever it is, with the VFD you are losing 5/6 of you horsepower from max to min speed compared to the Reeves. Even if the Reeves is 50% loss, and you put a 3hp motor on with VFD.....at the lowest speeds you're delivering half the torque as the mechanical with lower hp....if Forrest is right its more like 1/4 (2hp mech vs 3hp vfd)

I note the other considerations you mention, and that they may overshadow torque making it the best solution for someone, but the vfd is significant performance compromise per the above. Had the same discussion with P Eng's and they agree; if the mechanical reduction is there and working the VFD's a performance compromise.

notwithstanding, doesn't mean its a good solution for Bill....Bill PM me if you want a Canadian VFD source

MaxHeadRoom
09-10-2012, 10:26 PM
well that gives me lots to think about, any recommendations on VFD for this application?? and don't hesitate to recommend a seller.

I have used various makes over the years, on the Excello's I used Mitsubishi, but just because I got a deal at the time, but they are expensive now, the one I would look at is Hitachi, there are sellers on ebay for new product, They come in 1 ph and 3ph in, if you have 3ph available that would be the way to go.
Obviously if you leave the vari-speed on, you can leave it at one speed.
The 4 pole motor can also run at twice the rpm at 120Hz.
Max.

wierdscience
09-10-2012, 11:26 PM
I claim no expertise in this subject of Reeve efficiency, but here's an old post of Forrest's claiming 85-90% efficiency.



In ideal conditions they are,but seldom are idea conditions met.

Since most vertical B-port style mills are running an over drive ratio at the high end of both speed ranges they require more HP on that end of the range than in the lower ranges.Don't assume they need anywhere near that same amount of power at
lower speeds.

Besides the 3hp EVS setups are getting more and more popular.If the mfgs can do it,then so can we.

Checkout the Webb Champ 3 and 4.If I were buying new it would be a Champ 4EVS.

http://www.webbmachinery.com/Champ_series/webb_champ_mills.htm

wierdscience
09-11-2012, 12:00 AM
well that gives me lots to think about, any recommendations on VFD for this application?? and don't hesitate to recommend a seller. Having worked in shops my whole life I hate machines that make more noise than needed so I am leaning towards what wierdscience has said. The main thing is i don't want to drop $600 on a transformer and find out I went the wrong way. At least with you guys giving input I stand a chance of getting it right,,,, better than shooting in the dark.
Thanks

I've used these units from Automation Direct-

http://www.automationdirect.com/adc/Shopping/Catalog/Drives/DURApulse_-_GS3_(230_-z-_460_VAC_Sensorless_Vector_Control)/DURApulse_-_GS3_Drive_Units_(230_-z-_460_VAC_SLV)/GS3-23P0

In a new factory supported unit it's a good package at a good price.Never had any trouble with the units I have installed at home or work.

For $24.95 they offer an online training course that explains the various types of motors,drives and controls.I haven't tried it in particular,but have used one of their other courses and found it very helpful.YMMV

lazlo
09-11-2012, 09:46 AM
I claim no expertise in this subject of Reeve efficiency, but here's an old post of Forrest's claiming 85-90% efficiency.


I've always seen a ~ 75% efficiency figure. Aside from the Bridgeport example, my Clausing 5914 is 2HP with a Reeve's Drive, and the fixed speed version is 1.5 HP.

Like a Bridgeport electronic Varispeed conversion, the Excello would be fantastic with the 2-speed gearbox. With a 3 HP motor, you'd have full power over all the ranges, and it would be whisper quiet.

Bill McLeod
09-12-2012, 01:20 PM
This "With a 3 HP motor, you'd have full power over all the ranges, and it would be whisper quiet." comment from Lazo and what Wierdscience has said are pretty much what I am probably going to do. The 3 phase power I have is a roto phase and although it has lots of capacity I am thinking with a VFD I can run it off a single phase feed. is this correct? My reasoning is I believe power wise it's cheaper to run on single phase.
I really appreciate all of the input from everyone.

Mcgyver
09-12-2012, 01:27 PM
Like a Bridgeport electronic Varispeed conversion, the Excello would be fantastic with the 2-speed gearbox. With a 3 HP motor, you'd have full power over all the ranges, and it would be whisper quiet.

How do you figure that? You'd get 3hp at 640 rpm and 1/2 hp at 100 rpm (more less). VFD's keep torque constant so hp drops as frequency drops whereas mechanical maintains hp as rpms drop.

wierdscience
09-12-2012, 01:49 PM
This "With a 3 HP motor, you'd have full power over all the ranges, and it would be whisper quiet." comment from Lazo and what Wierdscience has said are pretty much what I am probably going to do. The 3 phase power I have is a roto phase and although it has lots of capacity I am thinking with a VFD I can run it off a single phase feed. is this correct? My reasoning is I believe power wise it's cheaper to run on single phase.
I really appreciate all of the input from everyone.

Yes,the unit I linked to is a single or three phase input unit,there are also several other makes that offer the same features.A VFD will generally be more efficent than an RPC and there is zero HP penalty.

MaxHeadRoom
09-12-2012, 02:14 PM
I am thinking with a VFD I can run it off a single phase feed. is this correct? My reasoning is I believe power wise it's cheaper to run on single phase.


Your can get 1ph and 3ph models also dual types, the Hitachi I mentioned come in two versions, the ones designed for 1ph beef up the power supply capacity to compensate for the lower efficiency DC supply on 1ph.
Especially running off a RPC, your cost would be around the same? Unless you are running the RPC solely for 3ph for the VFD.
Max.

quadrod
09-12-2012, 11:13 PM
This is the automation direct unit i used on my 602, http://www.automationdirect.com/adc/Overview/Catalog/Drives/GS2_(115_-z-_230_-z-_460_-z-_575_VAC_V-z-Hz_Control) it is single phase in and 3 phase out for two horse power
I used this because i have the 2hp pancake motor in three phase and only single phase hook up. I also have the GS2 drive on my lathe and a GS1 for the power cross feed on the mill.

MaxHeadRoom
09-12-2012, 11:32 PM
The only thing I would comment on there is this model is the simple Volts/HZ model, it pays to get the Vector control version, this offers electronic feedback to adjust RPM/current in the absence of pulse or encoder feedback. They are usually a small increase in price of the V/Hz model.
Max.