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  1. Replies
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    OK, look at the motor nameplate picture. The red...

    OK, look at the motor nameplate picture. The red is shown connected in with the blue and connected to "line 1" (high voltage).

    The black wire is connected with orange and white, and has no...
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    3 connections because 220V. For 110V, the...

    3 connections because 220V.

    For 110V, the motor's two windings are in parallel. For 220 the motor windings are in series. The start winding is 110V, so it is connected to the middle of the two...
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    The machine is an ENCO? Not an "EMCO"? OK,...

    The machine is an ENCO? Not an "EMCO"?

    OK, then the motor may be similar to the original motor, and the diagram may be related to the motor you have.

    If by chance is is an EMCO, the motor that...
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    Just to toss some numbers into the mix, here.... ...

    Just to toss some numbers into the mix, here.... A prior employer had an old 13" SB lathe in what passed for the toolroom.

    That machine had a spindle clearance spec which allowed from 1.5 thou...
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    Eh, you need to be more precise here.... PMDC...

    Eh, you need to be more precise here.... PMDC motors can have brushes, or not. Computer fans typically do not, treadmill motors have had brushes in general (that may change).

    You are correct...
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    The actual "RPM" is not very important. The...

    The actual "RPM" is not very important.

    The key issue seems to be the "oil shearing speed" of the spindle vs the stationary bearing. That will depend on spindle diameter, so the slower speeds...
  7. Thread: 608 Army Manual

    by JST
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    You can still find it at the link. The Army...

    You can still find it at the link. The Army manual does not apply to all versions, so there may be differences and items not shown or not present.

    Index of /Shaper...
  8. I did NOT know those were "universal" mills. I...

    I did NOT know those were "universal" mills. I wish the small horizontal I have was universal. I will think better thoughts about Burke mills in future.
  9. Yes, this can be an issue. If the voltage drops...

    Yes, this can be an issue. If the voltage drops enough to drop out the contactor as the motor starts, the motor may just "kick", but not start. Often the contactor will "buzz" as it goes through...
  10. Thread dials are usually either "4 inch" or "2...

    Thread dials are usually either "4 inch" or "2 inch" dials, with the 4 inch more common.

    The "inch" refers to how many teeth the gear has, a 4 inch has 4x the DPI, a 2 inch has 2 x the DPI. In...
  11. One of the mills here is a single slot, although...

    One of the mills here is a single slot, although the work envelope is probably bigger than what you describe.

    I found an L-W Chuck Co 6" swing (3" center height) dividing head that works very well...
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    OK, how about: "The welder DOES pull more than...

    OK, how about: "The welder DOES pull more than 30, since it pulls from the two 120V in SERIES, so it does pull up to 50A, and the one breaker is just the one that is set a tad lower than the other...
  13. Remember Forrest Addy? He had a claim that he...

    Remember Forrest Addy? He had a claim that he could clean an entire machine with a half pint of mineral spirits.

    So, one time I tried it on a machine I was cleaning up to sell. Dirty machine,...
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    The AFCI devices are really designed to work on...

    The AFCI devices are really designed to work on circuits that have reasonably well-behaved loads; lamps, etc, even computer power supplies don't seem to faze them.

    Intended to be used in bedrooms...
  15. Try nickel-iron instead? The damn things just...

    Try nickel-iron instead? The damn things just won't die.

    Hard to get, expensive, and don't hold a charge that long, but you can do almost anything except shoot holes in them and they will...
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    Source? Reasoning? Contactors on the DC side...

    Source? Reasoning?

    Contactors on the DC side are at risk if not rated for it. They may be AC contactors used well below their AC ratings for DC, and be "rated" for it even if that is not...
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    Definitely. Actually, a properly designed...

    Definitely.

    Actually, a properly designed stack is insulated so that the bolts etc holding it together are not shorting anything. The welded ones, which are welded down the lamination joint...
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    I could use the low ohms bridge and get a really...

    I could use the low ohms bridge and get a really precise reading, although the effort is not justified. The reading is certainly NOT a half ohm.

    Point being that there can be a fair amount...
  19. When reconditioning (as opposed to rebuilding),...

    When reconditioning (as opposed to rebuilding), pay attention to what you are working on.

    If the area in question is the filthy ways of a lathe, that are terrifically dirty, but basically in good...
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    That drive looks like it will do the 3 HP. Check...

    That drive looks like it will do the 3 HP. Check your motor current, the limit on the drive is 15A. Current is a better determinant than power with DC drives, just as with VFDs.

    I prefer, in...
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    Not to mention the fact that there are such...

    Not to mention the fact that there are such things as rectifiers, commonly used to develop 90V and 180V for DC motors off AC..... And treadmills have very commonly used that technique.

    AFCI...
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    Could be. There are iron losses, especially at...

    Could be. There are iron losses, especially at 50 Hz, which would come out of the 70 W, leaving less for copper losses.

    The half ohm seems low, I have a 1kVA transformer handy, and it...
  23. Never tried the pulse types, but I've never yet...

    Never tried the pulse types, but I've never yet had a constant current type charger bring back a battery to any reasonable performance.

    Generally, even if they did come back to nominal volts,...
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    And a forum for professionals.................. ...

    And a forum for professionals.................. Try the Home shop machinist, or that sort of forum.
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    The power indicated is not negligible; at 48...

    The power indicated is not negligible; at 48 volts for the system, that is 120W and about 70W. Not far off of what would be expected, although high for what the transformers are..... That is...
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