# motor for lathe



## tjwild (Nov 26, 2015)

Hello, 
I can not choose the electric motor to power the Jet lathe. The situation is following: the original motor is burnt. I contacted the manufacturer and their quotes for this part are high for me. Im going to search for used motor, maybe via the Craigslist. What brands are quality? 
If you have any suggestions or had similar issue, please share your thoughts with me.


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## RonGinger (Nov 26, 2015)

Buy a three phase motor and VFD. That will give you nice variable speed of the lathe.  I have h ad good luck with motors and VFDs from dealerselectric.com

It might be cheaper to find an old used motor, but the improvement to the lathe with a 3 phase is HUGE!


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## GLCarlson (Nov 26, 2015)

RonGinger said:


> Buy a three phase motor and VFD. That will give you nice variable speed of the lathe.  I have h ad good luck with motors and VFDs from dealerselectric.com
> 
> It might be cheaper to find an old used motor, but the improvement to the lathe with a 3 phase is HUGE!



another vote for dealerselectric. Great service. 

You may have trouble finding a 1-3 hp 3 phase on CL (or, without a VFD, checking it).  Most CL motor listing I've seen are for ancient, clapped-out junk, at prices that are 70-80% or more of new -that is, not worth it. Try a local motor rebuilder, service shop. Ebay is another source; some shops sell new at good prices there.


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## Grambo (Nov 26, 2015)

I use treadmill motors for all my repowering needs. People practically give them away. They are upwards of 2.5HP and you can strip the DC controller out of the treadmill and us it. it works great. I can send you some pic and instructions how to hook it up if you like


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## xpylonracer (Nov 26, 2015)

Hi Grambo
Do some of those motors have open ventilation slots ? 
I see some have 'Not reversable' on the duty plates, are the brushes not on centre of armature ?
I am considering this route at the present but it is difficult to get reliable info from some sellers.
Emgee


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## BaronJ (Nov 26, 2015)

Hi Emgee,

Have a look in your local scrapyard for Hoover, Hotpoint or similar front loading washing machines.  A lot of them have substantial AC/DC motors in them.

HTH.


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## Cogsy (Nov 26, 2015)

BaronJ said:


> Hi Emgee,
> 
> Have a look in your local scrapyard for Hoover, Hotpoint or similar front loading washing machines. A lot of them have substantial AC/DC motors in them.
> 
> HTH.


 
I know almost zero about electric motors but I tried to scavenge the motor from a 10 year old top loading washer for my power hacksaw. I figured it would spin at 1440 RPM (I'm sure most old motors used to) but this one spun somewhere between 10-15 thousand RPM!


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## ninefinger (Nov 26, 2015)

Dealerselectric for me too, and even though I'm in Canada they still were the best price.  I've bought from them 2 times now (vfd for mill and vfd and motor for lathe).
Just remember you are (most likely) looking for a single (1) phase input VFD.
You didn't mention the size of the motor but probably in the 1HP range.  Example motor: http://dealerselectric.com/E824.asp
Example VFD:  http://dealerselectric.com/FM50-201-OC.asp (I have this on my lathe).

Best thing you can do for your lathe!  Being able to speed up or slow down mid cut has saved me so many times...well worth it.
Also - 3 phase motors are robust - no capacitors to burn out or staring switches to get stuck, the VFD has soft start and lots of other nice features that you can play with, etc.  

Mike


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## tjwild (Nov 27, 2015)

I looked the prices for new motors and I think that I will try to search for the second used. Maybe I will be lucky to find something reliable. I want to have a motor manufactured in the USA. These motors are made in Arkansas as far as I know. 
https://www.mrosupply.com/motors/ac-motors/general-purpose-motors/26523_vm3546_baldor/ 
It is a 3ph, hz 60, hp 1, frame 56C , rpm	1725 . I will try to hunt for it on Craigslist. I will adopt my VFD to it.


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## Grambo (Nov 27, 2015)

Emgee, All treadmill motors I have come across in the USA is a brushed/vented/reversible DC permenant magnet motors. The motor controllers are Pulse width modulation (PWM). They are usually good up to 230VAC input. They use a DC-DC converter like transformerless wallwarts.
the pic shows a typical controller in a treadmill. Just gut it out and follow the AC cord to it. you also need the speed control knob on the riser.
Cheers
-Grambo


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## Grambo (Nov 27, 2015)

Emgee
All DC motorsit are reversible. Just reverse the polarity. I did that to mine and it spun off the counterweight pulley. I just locktite  on.
Cheers
-Grambo


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## dnalot (Nov 27, 2015)

Hi

I installed a treadmill motor and controler on my atlas 10' lathe about 5 months ago. It works great and was a very easy installation. So much nicer not having to change belts all the time. Here is a link to my post about it.

http://www.homemodelenginemachinist.com/showthread.php?t=24610

Mark


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## abby (Nov 27, 2015)

I can also recommend using a treadmill motor . I have fitted one to my BCA jig borer along with the power supply , it works beautifly,
amazingly small for the power output , the spindles are threaded LH for fitting the original drive pulley , I guess this is why the "non reversible " tag , as already stated you can easily work around this.


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## xpylonracer (Nov 27, 2015)

Thanks Grambo, in UK mainly brushed/PM/vented/180v so speed control not a problem and plenty of power, some go to 2HP at speeds up to 5500.
One concern is chips entering the motor.
Emgee


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## xpylonracer (Nov 27, 2015)

Abby, thanks for the input, especially the LH threaded pulley.
Emgee


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## BaronJ (Nov 30, 2015)

Cogsy said:


> I know almost zero about electric motors but I tried to scavenge the motor from a 10 year old top loading washer for my power hacksaw. I figured it would spin at 1440 RPM (I'm sure most old motors used to) but this one spun somewhere between 10-15 thousand RPM!



Hello Al,

The motor that you scavenged was almost certainly a brush motor and not a plain induction motor.  Induction motors cannot in of themselves run at speeds much more than 3000 rpm, whilst a brush, or more accurately a universal motor can easily exceed 15,000 or 20,000 rpm. 

I have a grinder that I built using a 1Hp universal motor and I feed it from a triac speed control to give me 5,000 rpm, though at those speeds vibration starts to become an issue.

The washing machine motors that I previously referred to are universal motors and generally around two Hp.  Some may remember the "Sinclair C5".  That used a modified Hoover washing machine motor and ran on two 12 volt car batteries.


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## MRA (Nov 30, 2015)

Has anyone any views on things to look for / avoid when considering buying a 2nd hand treadmill to strip?  There are a lot on ebay, and I'm not sure if they are much of a muchness, or whether some brands or types lend themselves more easily to this kind of thing, than others.

cheers
Mark


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## xpylonracer (Dec 1, 2015)

Sinclair C5 motor






Emgee


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## BaronJ (Dec 1, 2015)

Hi Emgee,

Those pictures show the Italian, Candy I think, manufactured motors.  Though the original ones were Hoover, made in Merthyr Tydfil in Wales.  Though I must admit I thought that they were more powerful than 250 watts.

In washing machine service they were driven by a switch selected thyristor controller manufactured by Mullard and then later a Triac one was used.  It was quite easy to bypass the switching and use a pot to get variable speeds.  They used a tachometer generator as feedback for speed stabilisation.  Hotpoint and others also used similar systems.


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## Chiptosser (Dec 1, 2015)

A point to consider,  the washing machine motor that you are referring to; are different voltage, than in the USA.  
They may not be the same in other aspects too, besides a designed rpm operating range.


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## petertha (Dec 1, 2015)

ninefinger said:


> Dealerselectric for me too, and even though I'm in Canada they still were the best price. I've bought from them 2 times now (vfd for mill and vfd and motor for lathe).
> Mike


 
My motors are still in good shape but the speed variability of VFD & especially slower speeds is something I would really enjoy when the day comes. Maybe sooner based on those prices.

Dumb question, but after swapping in motor/vfd on gearhead mills & lathes, do you just park in a midrange gear & control rpm through the blinky light box thereafter? Or maybe you can change gears the same way & this gives you even more rpm control options over stock fixed rpm motor? 

Also, are there any VFD issues or considerations to lathes that power on with the typical handle switch on the carriage? I thought someone mentioned you cant just turn VFD's 'on' like that or you needed a particular flavor.


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## ninefinger (Dec 1, 2015)

In general I tend to use my lathe as I did before; pick the right gear range for the surface speed of what you are wanting, but you can twiddle the speed to improve the cut if there is something going on at the particular speed you picked.  I've since started picking gears with my starting speed at ~ 40Hz an increasing to 60 or 70Hz as I get to smaller diameters to help keep the cutting speed the same as it was to begin (or closer anyway).
For the mill I'm a rank amateur (lathe too BTW), so I've pretty much done as above but the surface cutting speed doesn't vary as you go so I just adjust to find a nice surface finish.

As for turning on - yes - you no longer switch the AC to operate the motor. You give signals to the VFD.  So for my lathe I have a disconnect to the VFD, and I repurposed the Forward/off/Reverse switch to signal the VFD.  See the pics I took.  For the mill the same idea till I get the PC controlling the spindle (the mill is CNC now), however the control panel is a home made solution with: 
1. Variable speed pot,  
2. Forward / stop / reverse switch 
3. E-stop connected into VFD as an input as well 
4. The "start" button acts as a reset for the VFD if the e-stop is pressed or it faulted.

Hope that helps a bit
Mike
PS: writing this reminded me that I've intended to but not got around to installing an E-stop for the lathe at a spot down low in front of the carriage - MUST FIX (note to self)
PPS:  I  needed to add the vfd to the lathe as it came with a ~530 volt 3 phase motor that I could not power in my shop so conversion to something else was a necessity, and the vfd and 3 phase motor just made good sense.  The mill I bought with the 3 phase motor as an option for not much money so the vfd for it wasn't to cost prohibitive...(I recouped some money on the sale of the single phase motor too..)


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## zetuskid (Dec 30, 2016)

Grambo said:


> I use treadmill motors for all my repowering needs. People practically give them away. They are upwards of 2.5HP and you can strip the DC controller out of the treadmill and us it. it works great. I can send you some pic and instructions how to hook it up if you like



If the offer is still available, I would appreciate having done simple wiring directions on wiring the treadmill motor for the lathe. I have the motor and power controller but would like information on hooking up a tachometer and heat thermometer to the motor.
Thanks
zetuskid


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## stragenmitsuko (Dec 30, 2016)

There's a book in the workshop practice series about electric motors , what to look for and what not .
Could be handy if you don't know much about electric motors . 

I would definitly agree , a 3 phase motor and a vfd are the best choice . 
Most junkyards will have a motor section , and you should be able to pick up 
a small 3 phase for little money .

Pat


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