Need help with Grizzly lathe motor

T

terry sims

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I need some advice. I have a Grizzly G4016 lathe. I purchased it new 2 years ago and only have 60 hrs run time on it. Started it up today and the motor started to smoke but it continued to run. I can start and stop the motor but after 5 min the motor starts to smoke. Looks like I will have to replace the motor (2HP sp220V 1750RPM,TEFC) but Grizzly does not have a replacement in country. So I am thinking of replacing it with a name brand American made motor. Two choices come to mind 1) DC motor with variable speed control or an AC motor with a smaller pulley on the motor spindle so I can cut the normal speeds in half. If some body has recently replaced a Chinese lathe motor with an American motor I would like to know of potential problems in wiring ,mounting or changing speeds. Please hold the import bashing to a minimum as I have several Grizzly wood working tools that have held up over the years.
Terry Sims
 
Terry, the single-phase 3hp motor on my JET GH1340W-1 developed a problem in the starting circuit that a new set of contact points didn't solve, and since JET didn't have a replacement motor in-country at that time, they offered me $300 credit towards whatever motor I could find that would work. I chose to go with a US Motors 3-phase & VFD, and had a local electrician come out and wire in the VFD. Since I don't have 3-phase to my garage, I bought a TECO that converts 220v single-phase into 220v 3-phase, and have been completely satisfied with the results. The 3-phase motor runs smoother than the OEM single-phase did, and tolorates all the start/stop cycles gunsmithing imposes on a motor with no problems. The VFD has a speed control which would allow you to slow the motor below its rated speed, but if you're going to run slower with much of a load for any period of time, you'd probably want to go with a motor with a cooling fan that runs at full speed regardless of the motor speed - they're designed to work continuosly at lower speeds without overheating.

Another feature of the VFD that I really like is that you can program it to 'soft start' the motor - eg, I programmed mine to take 1.5 sec. to bring the motor to full speed. It's a lot easier on the lathe's gear train - I used to hear the gears 'snap' a bit when the single-phase would start.
 
You do NOT need 3 phase to run a 3 phase VFD.

The first thing a VFD does is full wave rectify the incoming power to DC, then create the 3 phase output waveform from the DC supply.
Unless you have a VERY large motor that would overload a 240 V supply, the 240 V will do just fine.

One of the most common problems with the import motors is the poor contacts ion the centrifugal switch for the start winding.
They can pit and drop voltage causing higher current in the winding damaging the insulation and further pitting the contacts.
Sometimes the start winding fails, sometime the contacts weld together and then the start winding fails.
 
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take it over to your local motor shop. they can fix you right up with a cheap replacement or rebuild yours with good parts. my local shop is very reasonable on individuals since his bread & butter is industrial stuff. he actually does my stuff free or at his cost since I do alot of business with him thru our plant. see if you can find an industrial maint. man and see if he can get it done for you thru his motor man cheap.
 
Butch Lambert said:
Brickeyee,
I don't think that Flatlander said that.
Butch
Click to expand...

Sure sounds like he did to me
Since I don't have 3-phase to my garage, I bought a TECO that converts 220v single-phase into 220v 3-phase, and have been completely satisfied with the results.
Click to expand...

There is no reason to have a 3 phase converter to supply a VFD unless you have a a VARY large lathe motor and cannot feed the VFD with 240 V.
A gunsmith size lathe is not going to have a motor large enough to overload the VFD input circuits when fed from 240 V.
 
brickeyee said:
Sure sounds like he did to me


There is no reason to have a 3 phase converter to supply a VFD unless you have a a VARY large lathe motor and cannot feed the VFD with 240 V.
A gunsmith size lathe is not going to have a motor large enough to overload the VFD input circuits when fed from 240 V.
Click to expand...

Brickeyee
Are there single phase 220 VFDs available or would one just use a 3 phase and run a single phase motor off it?
I did a quick search and only came up with single to 3 phase VFD converters.

Thank you in advance

James
 
Brickeyee,
He bought a Teco VFD to convert single phase to 3 phase for his 3 phase motor. He didn't convert it to 3 phase and then run it into the VFD. I think that you just misunderstood.
Butch
 
terry sims said:
I need some advice. I have a Grizzly G4016 lathe. I purchased it new 2 years ago and only have 60 hrs run time on it. Started it up today and the motor started to smoke but it continued to run. I can start and stop the motor but after 5 min the motor starts to smoke. Looks like I will have to replace the motor (2HP sp220V 1750RPM,TEFC) but Grizzly does not have a replacement in country. So I am thinking of replacing it with a name brand American made motor. Two choices come to mind 1) DC motor with variable speed control or an AC motor with a smaller pulley on the motor spindle so I can cut the normal speeds in half. If some body has recently replaced a Chinese lathe motor with an American motor I would like to know of potential problems in wiring ,mounting or changing speeds. Please hold the import bashing to a minimum as I have several Grizzly wood working tools that have held up over the years.
Terry Sims
Click to expand...


Terry - we will contact you tomorrow and get you taken care of. We have an in-house motor rewinding shop and even though it costs us twice what we can buy a new motor for, it is a service we provide to our customers. Granted, you are out of warranty, but I got some influence with the boss :).
 
My Import 14X42 lathe is 3 phase, I have single phase. I use a VFD and would not trade it for any other options. I think cost was about $250 about 5 years ago.
 
terry sims said:
I need some advice. I have a Grizzly G4016 lathe. I purchased it new 2 years ago and only have 60 hrs run time on it. Started it up today and the motor started to smoke but it continued to run. I can start and stop the motor but after 5 min the motor starts to smoke. Looks like I will have to replace the motor (2HP sp220V 1750RPM,TEFC) but Grizzly does not have a replacement in country. So I am thinking of replacing it with a name brand American made motor. Two choices come to mind 1) DC motor with variable speed control or an AC motor with a smaller pulley on the motor spindle so I can cut the normal speeds in half. If some body has recently replaced a Chinese lathe motor with an American motor I would like to know of potential problems in wiring ,mounting or changing speeds. Please hold the import bashing to a minimum as I have several Grizzly wood working tools that have held up over the years.
Terry Sims
Click to expand...

When you get it rewound, try to find out from the guys in the shop what the failure mode was. (moisture/vibration/insulation breakdown/overheating etc.)

It may help you from cooking it again.

Single phase motors are not very durable as a general rule.
 
Buy a 2-hp 3-phase replacement motor and a VFD and you will be very well pleased. Make sure your VFD is good for 4-hp since you only have 240 volts. If you buy a 2-hp VFD the startup will be too slow.
 
Shiraz Balolia said:
Terry - we will contact you tomorrow and get you taken care of. We have an in-house motor rewinding shop and even though it costs us twice what we can buy a new motor for, it is a service we provide to our customers. Granted, you are out of warranty, but I got some influence with the boss :).
Click to expand...


I love people who stand behind their stuff. When the time comes you just made a sale.
 
gosh darn, those are some great suggestions, where, were you guy's when I replaced my motor with a Century 1/2 hp A.C., I swiped from my household furnace ? :eek:
 
Never used that brand.

Putting a VFD any significant distance from the tool it is controlling is asking for trouble though.
The inductance (and resulting phase shifting) in the feed lines can play havoc with the control loops in a VFD.
 
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Motor update.

As you may have suspected from reply #11, my problems have been solved by someone with a lot of influence at Grizzly. The motor is now on it’s way to PA for a make over at Grizzly’s in house motor repair shop. It’s nice to know that they can do this if necessary. This is not going to cost me any thing except the one way shipping to PA. Thank you Shiraz Balolia may all your groups be small ones.
Flatlander& Jay- If I had to buy a new motor your VFD suggestion is the way to go. I would love to slow that machine down when threading up to the shoulder, besides if Butch recommends it, it must OK.
Dusty- Called around to some motor repair shops in LR with no luck. Most will not work on import motors any more and those that will charge half the cost of a new import to rework the starter windings. Ben- I think brickeyee is correct about the starter contacts failing as the starter capacitor was toast. Thank to all that replied to this post.
Terry Sims :)
 
Shiraz I need your HELP

Need help with a machine. I left a PM for you with some contact info.

Thanks
Dale
 
brickeyee....

Butch is right - what I was saying is, since my shop doesn't have 3-phase, I bought a TECO/Westinghouse VFD that takes single-phase input, and 3-phase output. This model has a max rating of 3hp, so the 3hp 3-phase replacement motor actually puts out its rated 3hp. It's mounted on the wiring pole right beside the lathe.

If I ever have any problems with the single-phase motor on my JET mill, I'll go the same route, with another dedicated VFD to control the mill's motor. Actually, after milling several scope bases out of 6061 T6 recently, I'm seriously considering some sort of variable speed motor control - either by converting to 3-phase with a VFD, or going to a DC motor w/speed control. I'm not about to go into production on this sort of stuff, but moving the belt from one sheave to the next sure gets old in a hurry.

Terry, it's good to deal with someone like Shiraz - wish he'd have had the gunsmithing lathes available three years ago when I was shopping for one. Glad your problem is solved.
 
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