My Delta Midi loses power.

[Tim Yanasak]

My Delta Midi ,model 46-250, is having a problem. The symptoms are:

– smells hot after a period of use
– will not start without manually spinning the headstock handwheel (after it starts smelling hot)
– loses power and slows down under load
Any ideas or direction as to how I can repair this is appreciated.
Thank You,
-Tim

 

[odie]

If it turns hard by hand, then bearings might need replacement.

Might need to be rewound.

Just a guess.....

ko

 

[Tim Yanasak]

odie,
Thank you for your quick response.
The lathe turns easily by hand and it runs smoothly so I don't think that it's the bearings. You mentioned that it might need to be "rewound", is it the motor that might need to be rewound? Because of the smell I do think that the problem is electrical maybe the motor.
Thank you for your help with this problem.
-Tim
BTW, odie, for some time now I have been a fan of your work and you have been an inspiration for my continued progress as a new bowl turner. Thank you for posting all those beautiful photos.

 

[Shawn Pachlhofer]

start capacitor is likely bad.

take the cover off the capacitor - if the end where the wires connect is "puffy" the capacitor is bad.

 

[Bill Boehme]

I'm pretty certain that that lathe uses a DC or universal motor. If not that then it would be a three phase AC motor (which it is not) and neither of those would have a start capacitor. Since part of my engineering career involved using motors in servo control systems, I very strongly suspect (in other words, almost absolutely positive)that some of the some of the armature windings have burned up. The facts that it gets very hot, has loss of power, and not starting in certain positions are all overwhelming indications of burned out windings. You also probably also smell the unmistakable aroma of ozone. The motor is a throw-away because no shop can rewind it for less than the cost of buying a new motor.

There is a slight chance that the brushes have worn out and damaged the commutator. If that is the case, it might be possible to repair the motor if the damage hasn't gone too far.

I suggest opening the motor and giving it a visual inspection. My guess is that you will see burned out armature windings sticking out radially.

 

[Tim Yanasak]

BINGO! Right on Shawn.
Not only is the capacitor puffed up mighty fat with black and brown goo oozing out it has that unmistakable nasty smell.
Thank you for leading me in the right direction.
Now where can I get a replacement? No luck with Delta, Granger online has something that will work but it is a little larger. I'll go down to the Granger store in the morning and just see if they find a better fit. If I find a good replacement I'll post it here.

It's rated at 30uF 5% and 300-VAC.
The physical is 3" long and 1.5" dia.
Thanks for the help.

 

[Shawn Pachlhofer]

other than Grainger, I would have no suggestion.

if it's not on their website, it's probably also not available in their store.

 

[odie]

Thanks Tim......I see you have your answer, great!

ko

 

[Rob Wallace]

BINGO! Right on Shawn.

Now where can I get a replacement? No luck with Delta, Granger online has something that will work but it is a little larger. I'll go down to the Granger store in the morning and just see if they find a better fit. If I find a good replacement I'll post it here.

It's rated at 30uF 5% and 300-VAC.
The physical is 3" long and 1.5" dia.
Thanks for the help.

I suggest you give Surplus Sales of Nebraska (Lincoln, NE) a call - they have thousands of motor start capacitors and are pretty helpful as to finding replacement parts. Phone: 1-402-346-4750

For quite a few years I have used them as sources for parts for multiple 'construction' projects, tinkering, and just building "stuff", as well as for ham radio parts, etc. They likely will have a unit of that capacitance and voltage rating that can be used with that motor:

http://www.surplussales.com/Capacitors/motorstart.html

Check-out Part Number: CS25-30X330 30 uF x 330 VAC - 1-7/16"D x 2-3/4"H

Good luck with your repair!

Turn safely,

Rob

 

[Owen Lowe]

Now where can I get a replacement? No luck with Delta, Granger online has something that will work but it is a little larger. I'll go down to the Granger store in the morning and just see if they find a better fit. If I find a good replacement I'll post it here.

Try Amazon - a quick "30 uf capacitor†search returned over 7500 hits.

 

[Bill Boehme]

I didn't read carefully enough and thought that you were talking about the variable speed version of the lathe.

If the capacitor starts to go bad the motor may not start or it may start very slowly. On some of these smaller motors, the capacitor stays in the circuit all of the time while in others, the capacitor is only used to start the motor and then it is kicked out of the circuit by the centrifugal switch. If your motor is the type that leaves the capacitor in the circuit while running then what you need is a RUN capacitor and not a START capacitor. The difference is that the START capacitor is not rated to operate full time. I would get the replacement capacitor from some place like Granger rather than going to Delta.

 

[Tim Yanasak]

Thanks for all the help folks.
I did buy the capacitor from Granger, it is larger then the original but then the original burned out. So I ran wires and mounted the new capacitor just behind the motor under the lathe bed. I think that my allowing wood chips to pile up on and around the motor contributed to the over heating of the motor and the capacitor. I'll clear out the chips as I work to help keep the motor cool and now the capacitor will not be affected by the motor's heat anyway. The Delta Midi is not my "dream" lathe but for small things it sure is fun and when it's broken the fun stops.
Thanks again for all the help.
-Tim

 

[Steve Worcester]

If you can get a part#, Digikey would be the way to go