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toolbreaker May 7th 10 06:23 PM

Jet lathe motor HELP
 
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


Tim Wescott[_3_] May 7th 10 06:33 PM

Jet lathe motor HELP
 
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?

If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.

So why not just fix the motor?

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

toolbreaker May 7th 10 06:38 PM

Jet lathe motor HELP
 
On May 7, 10:33*am, Tim Wescott wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.

So why not just fix the motor?

--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.

I am betting the cap is dependent on the motor speed. I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. I would like to have the cap in my hand when I tackle the
job. It is a chinese motor.

Joe Pfeiffer May 7th 10 06:47 PM

Jet lathe motor HELP
 
toolbreaker writes:

On May 7, 10:33Â*am, Tim Wescott wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Â*Turn it on and it
hums. Â* It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. Â* Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.

So why not just fix the motor?

--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.

I am betting the cap is dependent on the motor speed. I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. I would like to have the cap in my hand when I tackle the
job. It is a chinese motor.


Since you've got to do it sooner or later, do it sooner so you can get
the specs off the actual motor rather than possibly-informed guesses
from usenet.
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)

Jim Stewart May 7th 10 06:51 PM

Jet lathe motor HELP
 
toolbreaker wrote:
On May 7, 10:33 am, Tim wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.

So why not just fix the motor?

--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.

I am betting the cap is dependent on the motor speed. I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. I would like to have the cap in my hand when I tackle the
job. It is a chinese motor.


If it's anything like the motor that was
on my Jet 10x24, it's a piece of **** and
you shouldn't waste profanities and knuckle
skin on it. Mine had a problem with the
centrifugal start switch.

toolbreaker May 7th 10 06:59 PM

Jet lathe motor HELP
 
On May 7, 10:47*am, Joe Pfeiffer wrote:
toolbreaker writes:
On May 7, 10:33*am, Tim Wescott wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.


So why not just fix the motor?


--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. *Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.


I am betting the cap is dependent on the motor speed. * I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. *I would like to have the cap in my hand when I tackle the
job. * It is a chinese motor.


Since you've got to do it sooner or later, do it sooner so you can get
the specs off the actual motor rather than possibly-informed guesses
from usenet.
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)- Hide quoted text -

- Show quoted text -


Or the more likely outcome is that there will be no markings on the
capacitor (1980s chinese) and since it is dead I can't measure it.

toolbreaker May 7th 10 07:11 PM

Jet lathe motor HELP
 
On May 7, 10:51*am, Jim Stewart wrote:
toolbreaker wrote:
On May 7, 10:33 am, Tim *wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.


So why not just fix the motor?


--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. *Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.


I am betting the cap is dependent on the motor speed. * I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. *I would like to have the cap in my hand when I tackle the
job. * It is a chinese motor.


If it's anything like the motor that was
on my Jet 10x24, it's a piece of **** and
you shouldn't waste profanities and knuckle
skin on it. *Mine had a problem with the
centrifugal start switch.- Hide quoted text -

- Show quoted text -



What motor was on your 10 X 24?

I know chinese motors are often junk but this one has been in survice
for almost 30 years. A good part of that in production so it gets
some slack.

Steve Lusardi May 7th 10 10:06 PM

Jet lathe motor HELP
 
All caps eventually fail due to insulation failure. If you check the ratings on available caps, it is amazingly low. Thirty years
is excellent life. The cap is only in the circuit for a short time and actual size is not very critical. If it looks like it fits,
it'll work.
Steve

"toolbreaker" wrote in message ...
On May 7, 10:51 am, Jim Stewart wrote:
toolbreaker wrote:
On May 7, 10:33 am, Tim wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


If you can see capacitor goo then there's a good chance that all that
has happened is that you lost a capacitor, and a very slightly remoter
chance that you lost a centrifugal switch or some such and that took the
capacitor with it in time.


So why not just fix the motor?


--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com


I am going to rebuild it but I don't know what cap to buy. Plan is to
call the local motor rebuilder and ask for a cap for 2HP XX rpm motor.


I am betting the cap is dependent on the motor speed. I have to pull
the lath back from the wall to get to the motor and that is going to
be a chore. I would like to have the cap in my hand when I tackle the
job. It is a chinese motor.


If it's anything like the motor that was
on my Jet 10x24, it's a piece of **** and
you shouldn't waste profanities and knuckle
skin on it. Mine had a problem with the
centrifugal start switch.- Hide quoted text -

- Show quoted text -



What motor was on your 10 X 24?

I know chinese motors are often junk but this one has been in survice
for almost 30 years. A good part of that in production so it gets
some slack.


Gunner Asch[_6_] May 7th 10 10:10 PM

Jet lathe motor HELP
 
On Fri, 7 May 2010 10:23:22 -0700 (PDT), toolbreaker
wrote:

My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


Is it 3phase or single phase?

If you actually see capacitor goo..simply replace the capacitor. Ebay or
local shops generally have the proper one.

Gunner

--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

toolbreaker May 7th 10 10:28 PM

Jet lathe motor HELP
 
On May 7, 2:10*pm, Gunner Asch wrote:
On Fri, 7 May 2010 10:23:22 -0700 (PDT), toolbreaker

wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


Is it 3phase or single phase?

If you actually see capacitor goo..simply replace the capacitor. Ebay or
local shops generally have the proper one.

Gunner

--

"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." *Grey Ghost


Single phase. I don't think three phase motors need a capacitor to
start.

This post has gotten out of hand, I was hopping for a quick answer so
I could buy one on the way home from work and be all set to fix it
this weekend. I see that isn't going to happen. I want to get it
going I feel vunrable without my lathe.

Pete C. May 8th 10 12:09 AM

Jet lathe motor HELP
 

Gunner Asch wrote:

On Fri, 7 May 2010 10:23:22 -0700 (PDT), toolbreaker
wrote:

My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


Is it 3phase or single phase?


I haven't seen a lot of three phase motors with capacitors on them...

Wild_Bill May 8th 10 12:27 AM

Jet lathe motor HELP
 
This same question gets asked and generally answered on a regular basis, and
the archives can be searched thru a Goog Group search.

The Start capacitor in a capacitor start split-phase motor needs to be rated
for AC, and the value of the cap should be in the range of 500uF per HP, or
likely 500-750uF for a 2 HP size motor.
Additionally, the appropriate cap will be rated for 120VAC or higher volts
AC.

What you saw leaking may or may not be the capacitor electrolyte, but since
you haven't disassembled the motor, it's mostly speculation. There could be
a sheet of insulating material glued to the inside of the cap cover.
Only Eyes On will determine what it is.

As you won't know anything about the condition of the motor if you only
replace the Start cap, you should be prepared to disassemble the motor,
especially after 30 years of use.

You should examine the mechanical parts of the centrifugal switch mechanism
for wear or any other problems, and repair the parts if necessary.
The centrifugal switch contacts should be closely examined, and smoothed by
burnishing them, which is a better practice than filing or sanding them,
which leaves sharp ridges in their surfaces which tend to melt.

Bearings are cheap if the motor is ball bearing equipped (most likely).

An internal cleaning can remove some dirt from even a TEFC totally enclosed
fan closed motor. There may be loose paint, rust or other debris inside the
case, and significantly more dirt if the case is vented.

An ohm meter doesn't give any useful information about the condition of a
motor capacitor, unless the cap is shorted.

To confirm that an open Start cap is preventing the motor from starting, the
capacitor can be bypassed, with a safe, properly insulated connection (for
the dimmer ones that may read this, that means: Not a screwdriver or other
hazardous method), with the load removed from the motor.
Remove a drive belt or gear to separate the motor shaft from the machine.

A bypassed cap will allow the motor to start without a load, if the cap is
open internally.

A capacitor start split-phase motor will start and run normally with the
Start cap bypassed, and without the usual load applied to the motor.

The purpose of the Start cap in these motors is to increase the starting
torque rating of the motor to meet the application.
With the load removed, an good motor in otherwise undamaged condition will
start and run normally.

Other internal problems mentioned may prevent the motor from starting, which
is why one should be prepared to remove and disassemble the motor for
inspection when any problems arise.

--
WB
..........


"toolbreaker" wrote in message
...
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?



Wild_Bill May 8th 10 12:54 AM

Jet lathe motor HELP
 
And that's what separates you from the self-proclaimed professional machine
repair tech.. he does it for a living.

--
WB
..........


"Pete C." wrote in message
ter.com...


I haven't seen a lot of three phase motors with capacitors on them...



Gunner Asch[_6_] May 8th 10 08:23 AM

Jet lathe motor HELP
 
On Fri, 7 May 2010 14:28:50 -0700 (PDT), toolbreaker
wrote:

On May 7, 2:10*pm, Gunner Asch wrote:
On Fri, 7 May 2010 10:23:22 -0700 (PDT), toolbreaker

wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


Is it 3phase or single phase?

If you actually see capacitor goo..simply replace the capacitor. Ebay or
local shops generally have the proper one.

Gunner

--

"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." *Grey Ghost


Single phase. I don't think three phase motors need a capacitor to
start.

This post has gotten out of hand, I was hopping for a quick answer so
I could buy one on the way home from work and be all set to fix it
this weekend. I see that isn't going to happen. I want to get it
going I feel vunrable without my lathe.


Indeed. I was way tired when I read your original post..and it didnt
click. I came in from Los Angeles at 3:30 am..and was a walking doofus
most of the day.

If the motor has done you good service..simply change out the bad cap
with something similar. Some hardware stores stock em.

Gunner

--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

Gunner Asch[_6_] May 8th 10 08:24 AM

Jet lathe motor HELP
 
On Fri, 07 May 2010 18:09:45 -0500, "Pete C."
wrote:


Gunner Asch wrote:

On Fri, 7 May 2010 10:23:22 -0700 (PDT), toolbreaker
wrote:

My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


Is it 3phase or single phase?


I haven't seen a lot of three phase motors with capacitors on them...


Indeed. Mea Culpa. See previous post..no excuse..just an explaination.

Gunner

--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

toolbreaker May 11th 10 07:25 PM

Jet lathe motor HELP
 
On May 7, 4:27*pm, "Wild_Bill" wrote:
This same question gets asked and generally answered on a regular basis, and
the archives can be searched thru a Goog Group search.

The Start capacitor in a capacitor start split-phase motor needs to be rated
for AC, and the value of the cap should be in the range of 500uF per HP, or
likely 500-750uF for a 2 HP size motor.
Additionally, the appropriate cap will be rated for 120VAC or higher volts
AC.

What you saw leaking may or may not be the capacitor electrolyte, but since
you haven't disassembled the motor, it's mostly speculation. There could be
a sheet of insulating material glued to the inside of the cap cover.
Only Eyes On will determine what it is.

As you won't know anything about the condition of the motor if you only
replace the Start cap, you should be prepared to disassemble the motor,
especially after 30 years of use.

You should examine the mechanical parts of the centrifugal switch mechanism
for wear or any other problems, and repair the parts if necessary.
The centrifugal switch contacts should be closely examined, and smoothed by
burnishing them, which is a better practice than filing or sanding them,
which leaves sharp ridges in their surfaces which tend to melt.

Bearings are cheap if the motor is ball bearing equipped (most likely).

An internal cleaning can remove some dirt from even a TEFC totally enclosed
fan closed motor. There may be loose paint, rust or other debris inside the
case, and significantly more dirt if the case is vented.

An ohm meter doesn't give any useful information about the condition of a
motor capacitor, unless the cap is shorted.

To confirm that an open Start cap is preventing the motor from starting, the
capacitor can be bypassed, with a safe, properly insulated connection (for
the dimmer ones that may read this, that means: Not a screwdriver or other
hazardous method), with the load removed from the motor.
Remove a drive belt or gear to separate the motor shaft from the machine.

A bypassed cap will allow the motor to start without a load, if the cap is
open internally.

A capacitor start split-phase motor will start and run normally with the
Start cap bypassed, and without the usual load applied to the motor.

The purpose of the Start cap in these motors is to increase the starting
torque rating of the motor to meet the application.
With the load removed, an good motor in otherwise undamaged condition will
start and run normally.

Other internal problems mentioned may prevent the motor from starting, which
is why one should be prepared to remove and disassemble the motor for
inspection when any problems arise.

--
WB
.........

"toolbreaker" wrote in message

...



My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?- Hide quoted text -


- Show quoted text -


Great post. The 500 mircoF per HP is what I wanted to know.
Thanks.

Shabtai May 12th 10 05:26 PM

Jet lathe motor HELP
 
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.

it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?


I recently had the same failure on a grizzly 1236.
the caps were marked but I couldn't get the same size cap at Grainger.
I needed the lathe up quick so I wired new caps (replace both while
you're at it) in and made a new cover.

These are pretty standard values and ratings and the HVAC industry
uses them all.

Simon Shabtai Evan

toolbreaker May 17th 10 09:59 PM

Jet lathe motor HELP
 
On May 12, 9:26*am, Shabtai wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.


it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?


I recently had the same failure on a grizzly 1236.
the caps were marked but I couldn't get the same size cap at Grainger.
I needed the lathe up quick so I wired new caps (replace both while
you're at it) in and made a new cover.

These are pretty standard values and ratings and the HVAC industry
uses them all.

Simon Shabtai Evan


Update.

I pulled the lathe from the wall and looked at the capacitor. It was
bulging and leaking diametric all over everything. The failed
capacitor is factory supplied 110 VAC 600 microfarad beast. See
Granger for a selection of motor run caps. Note the motor runs on
220VAC. It is common for start capacitor to be rated at half working
voltage. This makes sense because the cap is sharing the voltage
with the starting coil so it only experiences ½ the run voltage.

I really needed the lathe for a job so I took a chance and replaced
the capacitor without checking the centrifugal cut out switch
contacts. I tested the motor and it appeared to work so I put
everything back together and started the job. Fifteen minutes into
it BOOM and the starter windings are shorted to ground. It was kind
of exiting because hitting the kill switch had no effect. Thank God
for circuited breakers. This time I pulled the motor and look at
the contacts and they are toast. I am now in the market for a new
motor and spent $700 having another shop make the part.



Tim Wescott[_3_] May 17th 10 10:20 PM

Jet lathe motor HELP
 
toolbreaker wrote:
On May 12, 9:26 am, Shabtai wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. Turn it on and it
hums. It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.
it is a 2 HP 220 VAC Capacitor start induction motor. Anyone know if
it is 1700 RPM or 3200 RPM motor?

I recently had the same failure on a grizzly 1236.
the caps were marked but I couldn't get the same size cap at Grainger.
I needed the lathe up quick so I wired new caps (replace both while
you're at it) in and made a new cover.

These are pretty standard values and ratings and the HVAC industry
uses them all.

Simon Shabtai Evan


Update.

I pulled the lathe from the wall and looked at the capacitor. It was
bulging and leaking diametric all over everything. The failed
capacitor is factory supplied 110 VAC 600 microfarad beast. See
Granger for a selection of motor run caps. Note the motor runs on
220VAC. It is common for start capacitor to be rated at half working
voltage. This makes sense because the cap is sharing the voltage
with the starting coil so it only experiences ½ the run voltage.

I really needed the lathe for a job so I took a chance and replaced
the capacitor without checking the centrifugal cut out switch
contacts. I tested the motor and it appeared to work so I put
everything back together and started the job. Fifteen minutes into
it BOOM and the starter windings are shorted to ground. It was kind
of exiting because hitting the kill switch had no effect. Thank God
for circuited breakers. This time I pulled the motor and look at
the contacts and they are toast. I am now in the market for a new
motor and spent $700 having another shop make the part.


Are the windings truly shorted, or did the cap fail short?

Bummer, if the motor really is toast.

Remember when you got motors rewound?

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

toolbreaker May 17th 10 10:33 PM

Jet lathe motor HELP
 
On May 17, 2:20*pm, Tim Wescott wrote:
toolbreaker wrote:
On May 12, 9:26 am, Shabtai wrote:
toolbreaker wrote:
My 13 x 40 Jet lathe motor gave up the goast. *Turn it on and it
hums. * It is against the wall so it is hard to see the motor but I
see capacitor gue coming out of it.
it is a 2 HP 220 VAC Capacitor start induction motor. * Anyone know if
it is 1700 RPM or 3200 RPM motor?
I recently had the same failure on a grizzly 1236.
the caps were marked but I couldn't get the same size cap at Grainger.
I needed the lathe up quick so I wired new caps (replace both while
you're at it) in and made a new cover.


These are pretty standard values and ratings and the HVAC industry
uses them all.


Simon Shabtai Evan


Update.


I pulled the lathe from the wall and looked at the capacitor. *It was
bulging and leaking diametric all over everything. *The failed
capacitor is factory supplied 110 VAC 600 microfarad beast. *See
Granger for a selection of motor run caps. * *Note the motor runs on
220VAC. *It is common for start capacitor to be rated at half working
voltage. * *This makes sense because the cap is sharing the voltage
with the starting coil so it only experiences ½ the run voltage.


I really needed the lathe for a job so I took a chance and replaced
the capacitor without checking the centrifugal cut out switch
contacts. * *I tested the motor and it appeared to work so I put
everything back together and started the job. * Fifteen minutes into
it BOOM and the starter windings are shorted to ground. *It was kind
of exiting because hitting the kill switch had no effect. *Thank God
for circuited breakers. * *This time I pulled the motor and look at
the contacts and they are toast. * I am now in the market for a new
motor and spent $700 having another shop make the part.


Are the windings truly shorted, or did the cap fail short?

Bummer, if the motor really is toast.

Remember when you got motors rewound?

--
Tim Wescott
Control system and signal processing consultingwww.wescottdesign.com- Hide quoted text -

- Show quoted text -


Dead short to case. 0.2 ohms.

I talked to the local motor rebuilder and at $75 hour he said it just
isn't worth it. New one cost $250 to $300.

Interesting thing. 22 mm metric shaft come out to 0.870. Now if I
had a lathe that worked I could bore out the pulley 5 mill and use a
n 7/8 shaft US motor.


Bob Engelhardt May 18th 10 12:50 AM

Jet lathe motor HELP
 
toolbreaker wrote:
...
Interesting thing. 22 mm metric shaft come out to 0.870. Now if I
had a lathe that worked I could bore out the pulley 5 mill and use a
7/8 shaft US motor.


Or you could take that US motor with its .875 shaft, clamp it down, turn
it on, & apply a file to the rotating shaft. .0025 from the radius
should be a piece of cake.

Bob

Wild_Bill May 19th 10 02:55 PM

Jet lathe motor HELP
 
There are some bargains to be found in used motors.. I try to keep several
spares for machines as backups, and for future projects.

Buying new motors isn't often a consideration for me, but I would if
desparately needed. A used 2HP 120/240VAC flea market motor cost me only $35
a few years ago.. a great Westinghouse ball bearing, air compressor rated
(start and run caps) in good condition.

A good alternate plan might be to find a variable speed AC or DC motor
setup.. they're a great upgrade for any lathe.

--
WB
..........


"toolbreaker" wrote in message
...
Update.


I pulled the lathe from the wall and looked at the capacitor. It was
bulging and leaking diametric all over everything. The failed
capacitor is factory supplied 110 VAC 600 microfarad beast. See
Granger for a selection of motor run caps. Note the motor runs on
220VAC. It is common for start capacitor to be rated at half working
voltage. This makes sense because the cap is sharing the voltage
with the starting coil so it only experiences ½ the run voltage.


I really needed the lathe for a job so I took a chance and replaced
the capacitor without checking the centrifugal cut out switch
contacts. I tested the motor and it appeared to work so I put
everything back together and started the job. Fifteen minutes into
it BOOM and the starter windings are shorted to ground. It was kind
of exiting because hitting the kill switch had no effect. Thank God
for circuited breakers. This time I pulled the motor and look at
the contacts and they are toast. I am now in the market for a new
motor and spent $700 having another shop make the part.



Dead short to case. 0.2 ohms.

I talked to the local motor rebuilder and at $75 hour he said it just
isn't worth it. New one cost $250 to $300.

Interesting thing. 22 mm metric shaft come out to 0.870. Now if I
had a lathe that worked I could bore out the pulley 5 mill and use a
n 7/8 shaft US motor.


Jimsshop January 13th 17 03:43 PM

Jet lathe motor HELP
 
replying to toolbreaker, Jimsshop wrote:
I have a jet 1336, the motor is 1720 RPM






--
for full context, visit http://www.polytechforum.com/metalwo...lp-237310-.htm




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