# 3 Phase Motor Shaft Modification For Profit!



## Ulma Doctor (Jul 10, 2013)

In my normal work, changing out motors is a constant part of my job.
Another part of my job is purchasing motors for replacement of OEM motors, iv'e gotten very good at it!!!
I have found over the years that most 3 phase motors are constructed in the same manner using similar parts.
The only thing that really changes is the size of the components the motor was constructed from and the materials the motor is constructed from as well. 
Not to say that all 3 phase motors are created equal, but rather, i'd say similar.
I have  Hobart Meat Saw model#5801 that has a faulty motor.
bear in mind this saw has operated for 6 years without any type of maintenance performed since it was new.
the Company that owns the saw pushed it into the corner when the motor started grumbling and left it there to rot.
The company was given a quote from the manufacturer to repair the saw.
The estimate was an astronomical sum that was more expensive than a new saw.

They gave me a call for a second opinion....
:notthis:
The manufacturer, Hobart is known for bending a customer over a barrel. 
The simplest of parts can literally cost the end user hundreds of dollars, and the manufacturer has no sympathy.
To add insult to injury, rarely does Hobart show up in the same week that a service call is placed, putting their customers who depend on the machinery in a real bad position. 
Hobart's attitude has made me a lot of money over the years, i hope they don't wake up to smell the coffee:lmao:

I got the call to inspect the saw from the newly contracted customer and reassured them i could make the saw purr like a kitten for less than the cost of a new saw.
I prepared the quote and the customer was nicely surprised as to the difference in projected cost to repair.
i was immediately issued a purchase order and authorized to continue my repair.
Hobart has a bad habit of making items OEM, and this makes going around their cute little system a difficult task sometimes...
They want you to buy anything for their machines from them. They will go as far as cutting special odd threads on certain bolts
just to trip independent service agencies from putting their hands in the cookie jar, so to speak.
Being in the business for a while and just having a think outside of the box mentality, has made me come up with many different was to skin cats of all names and manufacture. this case is no exception.
The motor from the OEM is a general electric manufactured motor. NOT AVAILABLE EXCEPT TO HOBART INC,:angry: and Hobart wants, now get this...$1,500.00 for a 3 hp 3 phase motor, i was told this by the parts rep for my area
:roflmao: was my response....

Knowing a lot about electric motors, i was not worried about finding a replacement. FR56CZ Code J was the OEM Frame
 The motor was manufactured to NEMA Standards, so that means other manufacturers manufacture the same frame.
If another manufacturer makes the same frame, they usually make very similar shafting configurations. 
The replacement i found happens to be a 56 J frame pump motor. It's manufactured by Century Motors


The only problem is that the motor is a plain shaft threaded to 7/16-20 male threads.
I need a Threaded and keyed shaft to retain a drive gear.
i disassembled the brand new replacement motor and removed the rotor assembly.
I trammed the mill and performed the set up to put a woodruff key in the 5/8" stainless steel shaft.
I clamped the rotor on 2 VEE blocks to keep it off Beatrice's bed


I was lucky enough to get a good tool score a couple months back, in the haul there were some pristine slot cutters!!!!:biggrin:
i Went to one of my Machinery's Handbooks and looked at the chart for woodruff keys the chart said #11, i just happen to have one to do the job!!:thumbsup:



i located the shaft and locked the X axis. 
I Touched off on the top of the shaft. i zeroed the dial and raised the knee .406" to cut on center of the 5/8" shaft
I touched off on the Y axis, zeroed the dial preparing to cut to a depth of .215" as to specifications.
I used a 50/50 mixture of Bacon Grease and Sulfured cutting oil on this run!!
the cutter was very sharp, even though the shaft end wasn't supported , i was able to take light pressure cuts with little resistance offered by the stainless steel shaft. 
i thought for sure i was going to have some issues, that fear was not to come truehew:

in the morning, i'll reassemble the motor and bench test before i make the trip to do the installation in the field.
I was able to purchase the motor for less than $400 shipped.
I'll still sell it for $1,500.00 and put the $1,100.00 in my pocket, i gotta pay for the mill somehow..
she just needs one more small job and she paid for herself!!!

I wish to encourage others who have been told you can't do this or that to prove them wrong!!!
You can do anything you devote yourself to, improbable as it may seem.
Think outside of the box!!!

Thanks for reading.
 I welcome questions and comments...


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## Tony Wells (Jul 10, 2013)

I love OEM just for that reason. I understand their objective, but I get immeasurable pleasure from taking advantage of their system. All it takes is a few good examples showing what can be done as alternatives, and you get some great customers. They are very grateful for saving them money, and you still make a nice, tidy profit on your smarts.


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## GK1918 (Jul 10, 2013)

Ecellent I have always thought that way.  50 yrs ago, same part different number, Lincoln 50 bucks more that a Mercury exact same part??


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## Tamper84 (Jul 10, 2013)

Very nice job Mike!!! I'm amazed about how some manufacturers do this. I've seen it here too. That's where the small guys come in and make some moola!!!  Great job and keep it up!!!:thumbsup:

Chris


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## woodtickgreg (Jul 10, 2013)

Very cool Mike, a great read, Way to go!


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## Ajax123 (Jul 11, 2013)

Great Post, very interesting story and educational too!

Ray​


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## Rbeckett (Jul 11, 2013)

Oh heck yeah!!!! Nothing I hate worse than a "proprietary" part.  Craftsman engines are well known for being only available from tecunseh through you local parts wharehouse at a huge profit to sears.  I used to buy a generic short block, and a crank from sears and just build my own for way less and always had the exact same engine.  No hassles finding parts later or weird modifications to concoct either.  Sometimes the crank would be undamaged and I could just get a short block and swap the crank.  Even cheaper.  I also used to modify the magnetic clutches that engage the blades from a generic unit to avoid the 300+ dollar OEM price tag.  Having a lathe and a mill has definitely opened the avenue for making repairs much faster than waiting for parts to arrive from some double top secret supplier in the vast waste land of Siberia somewhere.    One thing I do stress though, is be carefull what parts you modify and use.  Product liability issues being what they are now days you don't want to make a highly stressed part and have a failure that could cause an injury.  That's the reason I stay away from making blade shafts and blades.  Just too easy to have an issue that could cost me large later on.  Even your best friend will sue if his kid gets his leg cut off with a faulty part, so just use your head and a little common sense please....

Bob


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## Ulma Doctor (Jul 12, 2013)

One thing I do stress though, is be carefull what parts you modify and use.  Product liability issues being what they are now days you don't want to make a highly stressed part and have a failure that could cause an injury.  That's the reason I stay away from making blade shafts and blades.  Just too easy to have an issue that could cost me large later on.  Even your best friend will sue if his kid gets his leg cut off with a faulty part, so just use your head and a little common sense please....

Bob[/QUOTE]

Thank You Bob, for the wise advise!!!!
I would caution all the readers to make educated decisions in attempting modifications of any sort.
Sometimes, the education is in the failure created by the modification. 

On the OEM motor, the modification operation is performed by General Electric on the OEM motor shaft.
 i merely made the same modification for a non OEM motor in a controlled, measured manner.
In this project, the drive motor , drives a gear train. 
should there be a catastrophic failure in this modified part, the operation of the saw ceases immediately and no longer is a threat to the operator as no power is applied to the gear train that drives the wheels.


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## Ulma Doctor (Jul 13, 2013)

As an update for those interested...

The motor bench tested perfectly!!!!
I went down and did the procedure to the ailing meat saw. 
We had a complete success in the motor transplant!!! 
along with a motor transplant there were a laundry list of other things wrong.

Hopefully they'll be able to keep it working for a while but, i'm not holding my breath.

The operators are hard on their equipment.
these are the kind of guys who can break a bowling ball with a broomstick....
there's a reason they call them Butchers....


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## Armor (Jul 14, 2013)

Nice Job indeed.

Great to see the Thinking hat was on.

Jeff


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## Ulma Doctor (Jul 14, 2013)

Armor said:


> Nice Job indeed.
> 
> Great to see the Thinking hat was on.
> 
> Jeff



Thank you Jeff!!!

i try my very best to do the job better than my competition.

i'm happy that you enjoyed my story.
 if you or anyone has learned anything from my words or descriptions, i feel then, that i have contributed.
i write these type of threads to inform and/or educate my brethren on this forum as my primary reason for doing so!!!


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