Import Motors - Your Experiences?

[Frank Hagan]

In my quest for a new DC, I've run across a few comments from people about the import motors. One person said they had trouble with import motors on Grizzly equipment (specifically a table saw purchased a few years ago), while another had bad experiences with some Jet and General motors.

My Jet table saw is still running fine with its TEFC import motor in its fifth or sixth year, so I'm not really that gun-shy. But I was wondering what your experiences are with the motors on Grizzly equipment especially, and then also generally on other import equipment.

I'm already busting the budget on my plan to buy either a Oneida 2 HP DG or a Grizzly G0440, but Oneida has an upgrade path to a Baldor US made motor for another $150.

[Dev Emch]

Most import motors come from semi automated, overseas plants and are made as cheaply as possible. I personally consider most of these junk and when issues show up, it costs me in terms of my time (time == $MONEY$) to resolve their issues. I personally can no longer afford to track down and debug their problems. So usually pursue Baldor or Seimens when buying new and I prefer the Louis Allis DMD types when restoring old iron. Its a formula that works for us.

[Frank Hagan]

During the early 1990's, I dealt with the move from US manufacturing to the maquiladoras in Mexico, and it was a mess. Magnetek, AOSmith, Century and Franklin were all having all sorts of problems with quality issues. They eventually sorted themselves out.

Around that same time, there was an exact copy of an AOSmith design, at least cosmetically, coupled to an exact cosmetic copy of one of our pumps (they even copied the defects in the older mold we had). The motor was absolute junk and unsafe, but my experience with the import motor on my Jet table saw has been very good (as all the rest of my tool motors have been).

Does anyone compile stats on failures on these motors?

[Steve Clardy]

Only one problem with an import motor over the years.
Off-the-wall drill press I have, motor smoked. Got to squeaking, then let go. Come to find out it didn't even have a lower bearing in it. Shaft was fitted to the end cover. Replaced it with a dayton motor 1hp.

All my other equipment, 3 griz included, never had any bad problems.
I just did replace the centrifugual switch on the motor on my griz 1023 cabinet saw, after 11 years.
I'm happy.

[Mark Rios]

I just did replace the centrifugual switch on the motor on my griz 1023 cabinet saw, after 11 years.
I'm happy.

Wow...11 years on the 1023? that's a real saw. I'm really impressed. That puts Grizzly up another couple on notches in my book. I didn't realize a (seemingly to me) mid-price saw would have such longevity. Shows what I know. Makes me want to upgrade more now. I'll have to wait till after my BS and Jointer purchase though.

[Dev Emch]

Wow...11 years on the 1023? that's a real saw. I'm really impressed. That puts Grizzly up another couple on notches in my book. I didn't realize a (seemingly to me) mid-price saw would have such longevity. Shows what I know. Makes me want to upgrade more now. I'll have to wait till after my BS and Jointer purchase though.

Mark... Some of the old US motors are like Diesel Engines. They take a licking and keep on ticking. 11 years on a Louis Allis motor doesnt even show wear! I have seen GE motors used in early 1914 wallace jointers that are still running like a clock today. Just needed a drop of oil and a clean out. Since these older single phase motors were repulsion motors, you get some brush dust on the inside that needs to be cleaned out. The brushes were still serviceable and the commutator was factory new. Did not need to be turned and slited. My oliver jointer has a delta wind, 10 HP, 440 volt Louis Allis and the stator windings are mint and original!

My 1951 DeWalt RAS has a 7.5 HP motor which was under water for a few years. The bearings were shot and I needed to do a skim cut on the lower 1/3 of the rotor to remove about 9/10 ths of 1 thousandandths to true it up. The stator pack was steam cleaned and then baked out in my kitchen oven overnight. Installed new bearings and hooked it up. I figured that the stator windings were a gonner and I was prepared to fail my growler test and drag out the check book for a rebuilt motor from Wolfe or Original. NOPE! The motor jumped to life and purrrrrrssss ohhh sooooo smooth. Being careful on the rotor work on the metal lathe helped keep everything in crisp balance. But the stator windings were just fine after the steam cleaning and bake out. The DeWalt motor is unique which is why you just cannt slap any old motor into one of these saws. Hence the effort to rehab the old one.

I have rewound a few three phase motors and have been impressed by the quality of the older US motors. The single phase motors dont rock my boat because they tend to be a bit kludgy and often have what is called a tein winding (sp?). I dont know how to do tein windings and have no ambition to learn.

[Steve Clardy]

Wow...11 years on the 1023? that's a real saw. I'm really impressed. That puts Grizzly up another couple on notches in my book. I didn't realize a (seemingly to me) mid-price saw would have such longevity. Shows what I know. Makes me want to upgrade more now. I'll have to wait till after my BS and Jointer purchase though.

Yes. Used daily in my cabinet shop.
1 on=off switch
1 set of belts
and the centrifugal switch on the motor. [IMPORT motor]

[lou sansone]

any folks out there that work in the motor rewinding business. I think they would provide some good insight into this question. Even with domestic mfg there is a large variation of motor quality. Going further, even with the same mfg ( say reliance ) there are a variety of grades of motors.
lou

[tod evans]

i do not work in the motor industry but i did pay an old guy to educate me for a day several years ago.....in a nut shell he told me that the varnish used on the windings is what will make or break a loaded motor. if a person runs a motor at 70% or less of its rated amp draw even the cheep taiwan motors will be long lived, but the fellow who works his equipment will be best served by a motor constructed with high quality componants.

[Curt Harms]

I'm doing this from memory. Forrest seems to know what he's talking about-had a series of articles in a home machinist magazine that got good reviews. The gist is that import motors sometimes omit the final varnish dip & bake step.The wires of the windings vibrate, rub thru the too thin varnish, short out and that's it. His recommendation was to partially disassemble the motor and if you can get a thumbnail to move a wire in the winding, have it dipped & baked by a motor shop.

Again, I'm doing this strictly from memory.

Curt

[Ken Garlock]

Curt, I believe you have the correct information from Forrest Addy regarding additional varnish on the import motors. I don't know that Forrest ever gave an estimate of the cost of having the motor 'dipped.' However, it must be less than a new motor.

[Jim Becker]

This is a subject that is so easy to generalize...the source of manufacture isn't what is important. The quality and ratings of the particular motor is. And consider the warranty, too. I have never had a problem with the motors in any of the motors on the Jet, Grizzly or Delta machines I have owned. Do I prefer Leeson or Baldor or AEG (what is in my Mini Max machines)...yes...I know that the particular versions of these motors in my shop are really good. But even these companies make lower-end products...

[lou sansone]

This is a subject that is so easy to generalize...the source of manufacture isn't what is important. The quality and ratings of the particular motor is. And consider the warranty, too. I have never had a problem with the motors in any of the motors on the Jet, Grizzly or Delta machines I have owned. Do I prefer Leeson or Baldor or AEG (what is in my Mini Max machines)...yes...I know that the particular versions of these motors in my shop are really good. But even these companies make lower-end products...

that was exactly my point and why I hoped someone who works in the motor rewinding business would weigh in on this topic.
regards
lou

[Frank Hagan]

This is a subject that is so easy to generalize...the source of manufacture isn't what is important. The quality and ratings of the particular motor is. And consider the warranty, too. I have never had a problem with the motors in any of the motors on the Jet, Grizzly or Delta machines I have owned. Do I prefer Leeson or Baldor or AEG (what is in my Mini Max machines)...yes...I know that the particular versions of these motors in my shop are really good. But even these companies make lower-end products...

I think you're right on this. My experience with motors in the swimming pool pump industry was that manufacturers had several different price points for motors, with different ratings, etc.

In my research on cyclone DCs, it looks like only Oneida and Grizzly are offering class F rated insulation motors (rated at 311F ambient temperature), and most others are offering motors rated at class E (insulation rated at 248F ambient). Surprisingly, Jet's new cyclone dust collectors have just a class A rating ... 104F ... according American Woodworker.

My understanding is that the varnish on the windings is one of the elements that contributes to a higher insulation rating. So maybe the motors with an "F" rating have a higher probability of having the windings protected better.

Oneida says they have a two year warranty on their DG; does anyone know if that includes the motor? I suspect it is a standard 1 year warranty.

[Don Baer]

OK having worked in the motor and control industry for over 30 years I have found many instances where people simply don't understand about motors and there temperature rating. Rather then writing a tomb on the subject I'll just post this link for those who are interested in the subject.

http://www.motorsanddrives.com/cowern/motorterms4.html

If after raeding the link anyone has any further questions I'll be glad to anwer them.