Replacement Motor For 14x40 Lathe

jaychris

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I've been digging around the archives, but I still haven't found exactly what I need to know. I suspect it's because I don't really know a whole lot about AC motors in the first place. Enough to mount and wire one, but spec-wise... not so much.

I have a Jet GHB1440 - when I run the lathe in reverse and it starts to wind down, I can hear some pretty nasty grinding. Like I said, I don't know motors that well, but it doesn't sound good to me. It seems fine running in forward.

I figured I would buy a decent Baldor motor and that seems to be the common thread on posts I've found here. What I am not sure of, is which one to buy. My current motor is a 2HP and so this Baldor seems to fit the bill:

http://www.baldor.com/catalog/FDL3516TM

I'm just looking for input from guys with more experience than me, before I make a decision. Also, as long as I am replacing it, are there any other changes/updates I should make at the same time (different belts, isolation mounts, etc...)?
 
That should fit the bill. Check the frame size on your existing motor and make sure it will match up. The worse that could happen, the new motor frame size could be off slightly. Nothing that could not be fixed by drill new mounting holes. The pulley may not fit. May have to purchase a new one. Baldor has some nice motors. Their pricing is sometimes out of reach to some of us. I'm afraid to ask what they get for the motor? Shop around, that Baldor motor could be had for a lot lower than the retail price.
 
Bladors are very decent motors and last a long time, but there are many other brands that are also good. It is most likely that the mounting holes and pulley size may be different. You may also consider going to 3 phase and use a RPC or VFD, but adds to the cost and takes some electrical skills. A 3 phase motor will run smoother, and you will not have any issues with the start and run capacitors going in single phase motors. Have you tried to run your motor with no belt to see if the noise is there, or it is something in the gear train? Most of the single phase motors are about twice the price of a 3 phase motor, so you could buy a VFD and 3 phase motor for the price of a single phase motor, but then there is the wiring and programming.

Be aware that electrical boxes are in different positions, most metric motors they are on the top, vs US are on the side.

I would check eBay, you can often find great Baldor deals (with no shipping charge), and also on NOS in other brands. Might consider a 3 Hp motor if you have the space. There are also some killer 3 phase motors for $200-300. Another single phase Blador motor to consider is the L3516TM or EL3605T, the T has no overload protection built in, the TM has a thermal overload protector built in. All these are TEFC, sealed motors, the L3516 being general purpose for machinery, the EL3605 is a high efficiency and will draw a tad less current. The farm duty is a beast and is 1800 RPM, but not the most efficient power wise.
http://www.ebay.com/itm/L3516TM-2-HP-1730-RPM-NEW-BALDOR-ELECTRIC-MOTOR-/381147792910
http://www.ebay.com/itm/EL3605T-2-HP-1740-RPM-NEW-BALDOR-ELECTRIC-MOTOR-/201280840933
http://www.ebay.com/itm/BRAND-NEW-M...HP-1755RPM-1PH-60HZ-P-N-EL1408T-/331890308798

FDL3611TM
http://www.ebay.com/itm/BALDOR-2HP-1800rpm-182T-TEFC-1ph-AC-Motor-/291771262107

 
Don't give up on your existing motor too easily. Sometimes the centrifugal switch slip ring and brush in single phase motors makes noise as it re-engages while slowing down. That is an easy motor repair, if that is all it is. If you do not know about motors, it is probably smart to take your existing motor to a local motor shop and have them check it out. It does not cost much, and may save you lots of time and effort installing a new motor.
 
you may simply have a roller bearing failing in the motor.
i'd rip it out and tear it down for a closer inspection, if it were my lathe.

remove the pulley, mark your end caps position relative to the field winding and remove the retaining bolts.
knock the end caps off and inspect the bearings , being careful when removing the end opposing the shaft side, that's where the centrifugal switch lies.
once the end caps are removed, the rotor can be removed from the field winding for inspection.
extract the bearings from the rotor and replace.
inspect the field windings for signs of damage.
reassemble in reverse order and bench test to make sure you got things correct before installation
i hope the info is helpful :)
 
Don't give up on your existing motor too easily. Sometimes the centrifugal switch slip ring and brush in single phase motors makes noise as it re-engages while slowing down. That is an easy motor repair, if that is all it is. If you do not know about motors, it is probably smart to take your existing motor to a local motor shop and have them check it out. It does not cost much, and may save you lots of time and effort installing a new motor.


Thanks, maybe I'll do that before dropping the coin on a new motor.
 
you may simply have a roller bearing failing in the motor.
i'd rip it out and tear it down for a closer inspection, if it were my lathe.

remove the pulley, mark your end caps position relative to the field winding and remove the retaining bolts.
knock the end caps off and inspect the bearings , being careful when removing the end opposing the shaft side, that's where the centrifugal switch lies.
once the end caps are removed, the rotor can be removed from the field winding for inspection.
extract the bearings from the rotor and replace.
inspect the field windings for signs of damage.
reassemble in reverse order and bench test to make sure you got things correct before installation
i hope the info is helpful :)

It's definitely helpful. I may not know a lot about motors, but I have no problem at all jumping into one. The worst I can do is break it and then buy a new one and I'll have learned something along the way.

I'll take a short video of the noise and maybe you guys can identify the issue just from the sound. If it's something simple like you say, I'll take a shot at it.
 
It's definitely helpful. I may not know a lot about motors, but I have no problem at all jumping into one. The worst I can do is break it and then buy a new one and I'll have learned something along the way.
I'll take a short video of the noise and maybe you guys can identify the issue just from the sound. If it's something simple like you say, I'll take a shot at it.

the only thing i ask is,
that if you come to a place when you do not know how to proceed, in either disassembly or reassembly, ask someone how to go along. (either me or other fine gents here)
i'm happy to help you learn.
WARNING: there may be potential electrocution risk if you play with the capacitor.
see the video i made a while ago below:

 
the only thing i ask is,
that if you come to a place when you do not know how to proceed, in either disassembly or reassembly, ask someone how to go along. (either me or other fine gents here)
i'm happy to help you learn.
WARNING: there may be potential electrocution risk if you play with the capacitor.
see the video i made a while ago below:


Yep, I know electronics (and hence, testing/discharging capacitors), but appreciate the warning. Just never torn down an AC motor.
 
sorry, i didn't mean any offence . my concern was for your safety :)
this can be your very first time to rip one down!
 
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