Jet 1442 Lathe Replacement Motor?

[Damon Stathatos]

Russell - I can't attach these photos to a PM so thought that I'd just post it.

Any guess as to whether or not this one would work?

Jet lathe motor.jpg

Jet lathe motor specs.jpg

[Russell Neyman]

Well you definitely have an open circuit somewhere, you might rig up what I call a pigtail and hook the motor directly to a cord that could be plugged in to an outlet. That would at least verify that the problem is (or is not) actually the motor, I would hate for you to buy a motor only to find out the problem is not the motor. THE PIGTAIL IS FOR TESTING ONLY.

Did that. Not a squeak.

[Dick Strauss]

Damon,
The motor you are looking at is 3 phase. You will need to buy a VFD to run it but will also have a variable speed system you can adjust by turning a knob (electric speed control).

Your lathe uses a single phase motor from the factory with a reeves drive (mechanical speed control).

Unplug your lathe...check your switch (both sides should either be open (have near infinite resistance) or have near zero resistance). Dust often gets in there and prevents contact. If the switch is good, check to see you have near zero resistance on all plug-to-switch connections. Open up the switch to motor connections box and disconnect and reconnect all wire bundles as instructed by the motor cover plate. Check to make sure no bare wires are touching anything metal other than the connector and other wires. If you had the pigtail connected properly, you have ruled out the switch and cord issues mentioned above.

If it is the motor cap, you can often get the motor to run (when plugged in) by spinning the motor by hand and hittting the switch. If you try this, make sure your hands are nowhere near the fan or any other dangerous parts...!

Anything beyond this may mean you need a new motor.

[Russell Neyman]

Damon,
The motor you are looking at is 3 phase. You will need to buy a VFD to run it but will also have a variable speed system you can adjust by turning a knob (electric speed control).

Your lathe uses a single phase motor from the factory with a reeves drive (mechanical speed control).

Unplug your lathe...check your switch (both sides should either be open (have near infinite resistance) or have near zero resistance). Dust often gets in there and prevents contact. If the switch is good, check to see you have near zero resistance on all plug-to-switch connections. Open up the switch to motor connections box and disconnect and reconnect all wire bundles as instructed by the motor cover plate. Check to make sure no bare wires are touching anything metal other than the connector and other wires. If you had the pigtail connected properly, you have ruled out the switch and cord issues mentioned above.

If it is the motor cap, you can often get the motor to run (when plugged in) by spinning the motor by hand and hittting the switch. If you try this, make sure your hands are nowhere near the fan or any other dangerous parts...!

Anything beyond this may mean you need a new motor.

Thanks Dick. Yeah, many thanks to Damion but that's 220/240 and I don't want to run that. Besides, it looks like the mounting system is completely different.

As far as the various troubleshoots you suggested, I've done all of that. It is absolutely not in the switch, and I get nothing when I spin it in the on position. As I have said two or three times previously, I would normally think the motor was fried except there was/is no sign at all of heat or shorting. I'm headed over to Red's Electric in about an hour, and will let you guys know what I found out.

Walter Meier/Jet has a new one listed for $359. I might be able to use a discount certificate and order it through Rockler for less, too. If it's fried and Red's can't fix it, I'll go that route.

[Russell Neyman]

Problem solved today, but it isn't without a bit of drama, and several of the above posters deserve kudos. I took the motor to Red's (whom I highly recommend to anyone in the Western Puget Sound area) and before I could get back home, they called to say the motor was fixed. "The centrifugal governor was dirty and out of adjustment" they guy at the desk said. I trust these guys, but that didn't make sense, because I personally cleaned out the entire internal switching system, and I was positive it was clean and the connections were good. I shrugged, paid the bill, and went back to my shop.

Got home, reconnected and remounted the motor and I was all ready for things to return to normal, and....NOTHING... AGAIN.

OK, I thought, Red's guys eliminated problems within the motor, so it's gotta be somewhere back in the switch, which is the first thing I checked and one of the things the Sawmill Creek guys said was the likely cause. Now, I used one of those circuit checkers that lights up when you touch it to a wire, so I thought it checked out earlier, but....

To make a long story short, the switch was clogged up with a fine dust and was corroded, too, despite two fairly hefty seals that Jet engineered into it. Blowing it out with air and vacuuming it didn't work. I took it apart, cleaned it completely, put it back together, and everything works fine. I guess the switch conducted enough current to light the tester, but not enough to kick over the capacitor. Lesson learned from that standpoint.

The thing everyone can take from this is that, as turners, we deal with some pretty pesky sawdust that can get into everything, so we need to take precautions against this sort of contamination. Again, thanks to all of you who chimed in with good advice.

[Dick Strauss]

Russell,
I'm glad you got it figured out and I'm sure it was much less than a new motor! Hopefully they did a good job of cleaning and adjusting everything at the motor shop for a long and healthy motor life.

I suspect the issue was on the neutral side of the switch which is why I suggested you check the resistance on both sides of the switch. The hot side might have tested okay with power after the switch. However, both connections have to be good for the switch to work...so the neutral side needs to be checked for resistance to verify both contacts on the switch. The contacts can also get burned from the rush of current and may need to be cleaned or lightly sanded for a good contact.

Take care,
Dick

[Craig Matheny]

Russel also using a test light and a meter are two different things the ones that are light can pick up false reads and not tell you the true power/voltage that is available. Buy a cheap digital unit HF is fine but then you know if it is 120v or 60v. Good luck

[Donny Lawson]

No help here but I hope you figure it out soon. I hate to here the silence of a lathe not turning out shavings. I know when my shop burnt last year I went crazy until I finally got it started back up again. Good luck and let us know what you find out. There is alot of JET owners out here and it might help someone else later on.

[Russell Neyman]

Would you believe it?!! My turning buddy, Dave, came down just now, and he says his Jet 1642 EVS is working intermittently! He says it just stops when he's turning, and he has to hit the reset button on the inverter to get it going again. (That electronic variable speed setup is completely different than my 1442.) It's not his power source. This might be wearing a little thin, I realize, but any thoughts you guys have relative to this particular machine would be appreciated.

Having just gone through a similar situation -- as noted in this thread -- I'm going down to his shop early in the morning to help him trouble shoot. One thing you can be sure I'm going to do is check all of the switches and connections for dust contamination!! Stay tuned.

[Dick Strauss]

Russell,
This is probably not related to your issue. Not knowing the 1642 exactly but knowing the big brother (the PM3520), here is my stab in the dark for areas to check...

-Make sure your friend is using the low speed pulley when turning larger pieces, otherwise the motor will stall and you will have to reset the inverter as reported by your friend (this issue is the most likely by far). It may also stall the motor if the tools are wrong, dull, or the bite is too big.
-secondary switches may be a problem (as applicable)...the primary will not have the same issue because it relies on contact blocks to make the connection.
-check the input voltage to make sure that it is within spec at the wall outlet. If you are at the end of a power run in the country, you may experience temporary voltage sags as demand increases upstream.
-inverter parameters may have been changed or the inverter might be bad
-motor is overheating or defective

If you can get more specific details as to the size of the piece being turned, what tools used and how sharp, low or high pulley, how long has the lathe been running when the issue occurs, etc, it will make it easier to track down the issue. If the lathe is still under warranty, you will probably want to contact WMH (parent company to both Jet, PM, and Wilton) if options 1, 2, & 3 are verified not to be an issue.

[Russell Neyman]

If we were to check to see is the inverter has gone bad (the likely culprit, since it hums when the lathe has quit) how would we do that?

[Bill Wyko]

My JET did that a long time ago. It turned out to be a bad crimp on one of the wires. The wire was connected to the connector but the wire was broken in the insulation. Good luck. Do you have a continuity meter?

[Bill Wyko]

That says it's a 3 phase motor. Do you have 3 phase power to your shop?

Russell - I can't attach these photos to a PM so thought that I'd just post it.

Any guess as to whether or not this one would work?

Jet lathe motor.jpg

Jet lathe motor specs.jpg

[Russell Neyman]

The odyssey involving the Dave's Jet 1642 took a somewhat astonishing turn -- for the better, I guess -- and it's worth sharing. He and I got together crack of dawn yesterday to troubleshoot the system following the same steps I used with my 1442. We pulled all of the switches, cleaned them thoroughly, and looked for the crimped wires, etc. We also checked voltages at various points along the circuit. Machine still occasionally quit and made that humming sound, and the inverter shut down. To restart it, we had to hit the reset button on the bottom of the inverter, and even then is often wouldn't go.

Frustrated, we backed off, and Dave got ready to call Jet to order a new inverter because he was convinced that was the problem. I sat in a chair across the room, drinking a cup of coffee, taking a good long look at the situation. Sitting atop the headstock was a small wood bowl that Dave used to keep spare jaw screws and miscellaneous small parts. In an instant, the old noggin lightbulb clicked: "Dave, is that bowl magnetic--?" "Yup," he said, "I put several Rare Earth magnets in the base, to hold it in place and to keep screws from bouncing out." "Well," I said, "it's right over the RPM indicator. Do you think those magnets could be affecting the electronic controls--?"

It was an ah-hah moment. We moved the magnetic bowl to the lathe bed, and -- poof! -- problem gone. That bowl had been there for months, but he often shifted it around while working. So, probably, when he moved it to the area near the LED RPM control it would affect the sensitive electronics just enough to shut the system down.

Just goes to show you that the smallest choices can affect and entire situation. Thanks for everyone's help and suggestions. Hopefully, somebody who has similar issues with these two lathes down the road will use the Sawmill Creek "search" feature, discover this thread, and save themselves some grief.

[Damon Stathatos]

That says it's a 3 phase motor. Do you have 3 phase power to your shop?

Bill - I didn't want to create any confusion in this thread with my post and pictures of my new Jet motor. Russell had originally posed the question about whether or not he may need a new motor. Since then, he is seems to be on his way to a solution to his problem. He had also determined that this is a different motor mount type than his.

My story is that I had this new Jet motor (the motor that I was offering to Russell) that I had purchased off of a Creeker about a year ago. My original plan was to replace the motor in my PM90 which had been previously retrofitted with a single phase delta motor. Although there was another post stating that most PM90's were single phase, whenever I run across them, they are mostly 3ph. My motivation to switch my PM90 back to 3ph was that I could then incorporate it with a VFD to lower the minimum rpms, which is currently 1000. When I first got the lathe, I was concerned that the Reeves drive on the PM90, with it's minimum 1000 rpms, would eliminate my chances to rough out bowls and delegate the lathe to pretty much spindle stock.

After I got the new Jet motor, I realized that I could probably make it fit into the limited cavity where the existing motor is but that I'd also need to fabricate a new mounting plate to accommodate the different frame style. Laziness set in at this point and then, in time, I began to dare roughing out bowl stock at what I had previously thought too high an rpm and have had some success with that. I'm not on a lathe 100% of the time, the lathe is a diversion for me rather than my regular fare, so it seems to be working out for me fine. This thread has almost re-sparked my original interest in the ability to slow my beast down and so the next time I see my neighbor (a metalworker) I'm going to talk to him about the possibility of a new mount for this new Jet motor.

Finally, to answer your question, I do have 3ph power in my shop, both 220 and 440, although in this case, with a VFD, it wouldn't be necessary. Most all of my machines are 3ph except a cluster of single phase 220 machines from my original garage shop, (clustered together because I only have one 220 1ph line run, again, laziness).