Machine shop phase converters from the old days

[@danneumann3274]

I started working for an old man many years ago. He had a shop behind his house and We had to rope pull a big old motor for our 3 phase. I have found that 1725 motors are quieter and easier to rope start. 3450 rpm motors are loud and hard to hand start. i liked the big old motors that were large in size where the armature had a lot of mass. these seemed to slow down less when reversing my lathe. I did put a small 1/4 horse motor that I used for starting later on. put power to the small motor then it would disconnect and apply power to the large motor. I liked having my converter motor double the horsepower of my largest machine. nice informative video

[@deedeeindustrialsuperprecision]

One of the things a couple of old machine tool dealers said years ago is that high speed motors have a better phase angle, but others have said 1150 rpm motors are the best, I really don't know the answer to that, and I have used a variety of motors. The Monarch 10ee motor generator is 3400 rpms with a very heavy dual armature, I had a 25hp homemade set up that I ran a 20hp lathe with it had the 1150 rpm motor worked good also.

[@charleskutrufis9612]

My first one was fancy, I used a washing machine motor and a belt I could tighten to start the 3 phase motor. many, many years ago. lol

[@bid6413]

Dee Dee, That rotary phase converter you built from the old 10ee motor/generator is quite a piece of work. I love it. Great introduction to how to get 3 phase power cheaply. I didn’t know about the smart meters; thanks for that info. I know that there are KZbin “how to” guys showing phase converter builds if a person really wants to save money. I made my own so it can’t be too difficult. I set mine up outside to keep the noise out of the shop. Instead of a manual switch to turn it off and on I am using an high amperage motor starter and control its’ coil with a 110v wireless remote. I know a guy in Walla Walla who found a 100hp motor in a salvage yard if anyone really wants power! Cheers, Will

[@deedeeindustrialsuperprecision]

That inrush or high amp draw charge is high and adds up. The simple method of starting an idler motor with a rope is good to know in an emergency or just to test machines that have higher HP then your current system, never know what will come up in my adventures. I am going to make a little compressor and phase converter shed outside heavily insulated for cheap compressors.

[@terrycannon570]

@@deedeeindustrialsuperprecision I have my compressor inside another building and ran copper underground. Also ran my welding leads underground so i can weld in both shops. Very interesting about the smart meters. I did not know they could tell the price of oil has doubled. They must because my electric bill has tripled in the last 2 years and I am actually using less electricity. I get a weekly daily usage and daily cost emailed to me every week and a monthly forecast of what my bill is going to be. I save all those weekly reports and I'll be damned they were within $2.04 of what my actual bill was . Kind of makes me wonder if the game is rigged ! lol

[@bid6413]

@@deedeeindustrialsuperprecision You’re a considerate neighbor; I don’t have any so all I needed was a little protection from the weather. Thanks lots for sharing what you know about rotary phase converters. I am using the one I made over 25 years ago. I used an 18hp Fairbanks-Morse hollow shaft turbine water pump motor. The angular contact ball supporting the armature is in an oil bath. It will outlive me. 8 amps at idle. You’re an adventure to follow. Cheers, Will

[@kentuckytrapper780]

Great info Dee Dee, I run a 7 1/2 hp static phase-a-matic converter, no problems in the past 3 years. Great video, keep'um coming.

[@deedeeindustrialsuperprecision]

Those have worked for me, if you get a smart service meter adding an idler motor could save money.

[@taylorcraft1947]

deedee, having a lot of experience with both phase converters and generators, I feel that I need to clarify to others watching this video that your setup with the 10ee rotary converter and starting capacitors is not the equivalent of a commercial phase converter. I have run into a lot of people that don't understand this. As you said, this is something that "you can get by really cheaply" with. I have done this with a similar setup (7.5 hp 3-phase motor with pushbutton starter capacitors), but I was not actually getting balanced 3-phase power. I was essentially running the motor on 1-phase with the converter acting as a transient starting aid for the 3-phase motor on the machine. In technical terms, with this setup, I got 3-phase voltage all the time, but only 3-phase current when the load was changing. This was enough to start the machine's motor, but I got crummy loaded performance on the lathe, band saw, drill press, and metal shear that I ran with it. The next step up from this is a switching converter, next a rotary converter, and best is 3-phase directly from the actual power grid. By the way, I now have a commercially made rotary converter in my shop.

[@deedeeindustrialsuperprecision]

I have had utility 3 phase in a few locations and it can be Badly unbalanced, I can not tell any difference unless its 440v in one machine. I cannot detect any imbalance problems at all. The first I have heard of this problem is from folks that have little experience with machines and more with electronics. I dismiss it as a problem totally.

[@bid6413]

@@deedeeindustrialsuperprecision I agree, rotary phase converters get the job done and relatively efficient and inexpensive to make. The rotary phase converter is never going to be perfectly balanced. Every time you switch another motor on the phase angle is changed a little. All that said, I’ve done extensive testing of both current and voltage balance and while the power isn’t perfectly balanced it is good enough if you’ve got your run capacitors balanced. My rotary phase output is able to power old motors, modern motors and my Bridgeport EZ Trak’s CNC functions and I have never had a problem in over 30 years of use. Now, I am not running my motors at their maximum hp most of the time but I do use the instant reverse capabilities of 3 phase a lot. I’ve never used one, but is my understanding that high end rotary phase converters use solid state capability to sense and adjust the power each leg is delivering, but again it is a lot more expensive than making your own. I haven’t read anyone talking about 3 phase welders and you can easily do that with a rotary phase converter. For years I have used my rotary phase converter to power my R3S-600 Lincoln Mig power supply and LN-7 wire feeders and it has worked beautifully. Using VFD’s or Vector to convert 1 phase to 3 phase power has some advantages and will provide better power balance, but I think you’d need a unit for each tool and they are so expensive.

[@deedeeindustrialsuperprecision]

@@bid6413 I tried to find a difference that I could see on the work, I just simply could not find a noticeable problem. I do not have to really push machines hard because I am in service and repair. Also, I have never not once heard of anyone burning a motor up using a static converter either. I have dinked around with run caps no difference there. The utility 3 phase can be bad in my area because of old infrastructure from the 1930s rural electrification, it can be badly unbalanced and require a power conditioner. My view is the whole thing is a bunch of non sense cooked up on the jerk off forums by those that machine nothing at all but look at meters, then panic. I also find it amusing that the racist approved dud machinist are blatantly hocking a particular brand of commercial rotary phase converter. Is it because the cant make their own or did they get a free one? In my opinion only, this non sense about phase converters is another non issue barrier for those that want to join in on the fun of having real industrial machinery instead of that import Precision Matty garbage! Phase converting is easy and cheap and always has been.

[@taylorcraft1947]

@@deedeeindustrialsuperprecision I have experienced what happens with imbalanced three phase first hand. Basically, the motor doesn't run smoothly and slows down more easily than it should with application of load. Some of the lack of torque/soft torque response is also due to imbalanced power factor at different load conditions. To fully compensate for changing load you need your own active system, or you need to tap into a stiff system with guaranteed balanced power factor (ie the utility company). In my area (Flint. MI) the utilities are very good and underloaded because of the exodus of General Motors and all of the supporting population (Also, we have no smart meters to deal with!). The problem that I had was paying my share of the cost of running 3-phase power a few miles down the road and up the 1500' driveway to the shop. The specific problems that I experienced with the "static converter" setup were: The lathe would not run the depth of cut that I was used to when cutting 1" linear shafting to length with the proper inserts. The rigidity was sufficient, the chip curl was coming off red/orange like it should, but the motor would not keep up that way it was supposed to. I could only take a 0.015" deep cut and should have been able to take a 0.025" cut easily. It didn't stop me from getting the job done but made it take twice as long, and with 25 parts, this added over an hour to the job. I ran into the same problems with large drills (1"-1 1/2" diameter) bogging down the motor in mild steel. Also, I could not start the 8' metal shear reliably with the same converter setup. It would work once started, but at much reduced capacity. I could start it with a welding generator, and then run on the converter once the flywheel was spinning, but this defeated the purpose, since it would shear better with the generator anyway. Most of the time, the lower capacity was not a problem, but sometimes it was, and it was worth it for me to get an inexpensive commercially made rotary.

[@taylorcraft1947]

@@deedeeindustrialsuperprecision You are right dee dee, the static type of converter does work, and work well enough for most purposes. I use one myself on a regular basis. I would also like to encourage anyone who sees the cost of a commercial phase converter as a roadblock to consider the option of making one out of an electric motor. It is dead simple and cheap. Just make sure that you have some help or advice from someone who has experience with electric motors and wiring if you have none.

[@mjm7187]

Thanks for the details on this procedure, great to see a video from a seasoned journeyman!

[@deedeeindustrialsuperprecision]

Thanks for tuning in!

[@terrycannon570]

Very interesting dee dee. I have yet to get 3 phase power. My Clausing 5913 that I am restoring has a 2 hp 3 phase motor on it and I have tried 2 different VFD's and the motor does not run . I saw the lathe run from a rotary phase converter when i bought it. So I am baffled. Some say that all 3 phase motors will not run on VFD's. I will be taking it to the rewinder's shop soon to see what the issue really is.. I am trying to keep the lathe original so have not yet considered buying another motor. BTW it is 75 degrees here today.

[@terrycannon570]

@@melgross so what am i looking for on the motor plate?

[@deedeeindustrialsuperprecision]

The Clausing are nice machines, not many around here. I have not got into the VFD yet I would like to try one on a woodworking machine. The motor shop I used is long gone I resort to testing motors using other motors that I get spinning before engaging the power. Then have a switch to juice the motor to be tested.

[@terrycannon570]

@@deedeeindustrialsuperprecision I am weak when it comes to electrical knowledge. I have tested it with a meter and it test good but i do not have a way to meg ger it or a way to run it without the VFD. The first VFD would make it run but at very low RPM then fault out on over load. The second larger VFD would not even turn it . It just faults out. So I will just have to pay for professional diagnosis. Most motor shops around here want the Industrial business and do not want to mess with a Hobbyist. Thanks for the response, BTW if you do get a VFD be prepared to read Chinenglish lol the instructions are terrible.

[@deedeeindustrialsuperprecision]

@@terrycannon570 The motor shop should charge minimal, I used one for years until they closed up. I think your machine is a variable speed with a reeves drive perhaps a rotary converter might be better.

[@terrycannon570]

@@deedeeindustrialsuperprecision I may wind up with a rotary converter . I went with VFD because of cost but now I have enuff invested in the two VFD.s to pay for half of a rotary. I was mainly trying to avoid the noise of the rotary. You are correct about the Reeves drive. It worked when i bought the machine. I took it apart to paint the headstock so hopefully it will still push fluid okay.

[@kensmedberg1130]

Good content .. I'm hoping I can find an old 10+ HP 3Ph motor to generate power for my old 4 Hp (GE/Westinghouse?) motor on my old surface grinder using the utility's single phase . The 4HP is a good ol' motor -- worked fine when I had 3Ph power. The motor is at least 80 yrs old -- delivers power to leather belt drive .

[@deedeeindustrialsuperprecision]

My big machines are 80 yrs. old too, those motors were heavier built, the 1940s GE 3hp on my radial drill is the size of a modern 15hp motor. There are a lot of surplus motors here, but I notice they are being slowly bought up.

[@erikclausen4780]

I real enjoyed the show of 3 phase converter great information Thank you for sharing the info.

[@deedeeindustrialsuperprecision]

Thanks, I am a bit old fashion on this subject

[@johndeere772002]

I can’t believe utility companies are going to charge based on instantaneous current demands… Also, that phase converter does a good job at portraying rotational inertia - ie, that large copper mass is little effected by demands in instantaneous current (when you turn on your machines). Versus the static converters that have little ability to ‘absorb’ and compensate for that instantaneous demand. On a larger scale, this is the same effect on electrical grid stability and the ability of the 100+ tons of rotational mass of a steam turbine to compensate for instabilities (synchronous generator coupled with the grid); in essence a mechanism for grid stability. Compared to the static generators like solar and wind (asynchronous generator) which has no ability to compensate for minor grid instabilities. Hence the reason the utility is monetarily penalizing for large instantaneous current demands - we’re losing the ability to compensate for grid instability, so the utility will combat this by penalizing those who greatest the grids stability. Hmmm interesting….

[@deedeeindustrialsuperprecision]

From what I have heard it was mainly directed at air conditioning use that generally can have high start loads. I have heard that lathes with a clutch saves considerable if one only is using a static converter. American rotary provided a 15hp converter after my 7.5 simple homemade thing gave out. This unit is providing the best running I have had in the area here but the utility structure is very old with out of balance 3 phase in the rural areas.

[@charleskutrufis9612]

Like you I have used phase converters both home made and store bought. A question please, the static converter you are using to start your primary 3 phase motor, is the static converter pulled out of the circuit once the primary motor is started?

[@LaLaLand.Germany]

Man, I must admit You Mericans are quite screwed with the 3phase power... In Europe we have 240 3phase at every house but that´s the only plus ;)

[@deedeeindustrialsuperprecision]

Yes, everything about 3 phase cost more, huge expense in new construction.

[@dutchgray86]

I'm lucky that my shop has real 3 phase, 3x 100A 400V. So everything is easy but all the breakers and switch gear is expensive.

[@deedeeindustrialsuperprecision]

Everything about utility 3 phase in my area is super expensive, lots of regulations you pay much more for it. Tens of thousands extra cost to add to construction, over $30000 to install in a small exiting building.