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  1. All this verbiage over a simple problem. ...

    All this verbiage over a simple problem.

    Transformers do care what frequency they are run at because the cycle time determines the time the flux has to approach saturation. The other factor...
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    DC motors do break down occasionally. I had one...

    DC motors do break down occasionally. I had one that extended the boom on one of Gannet's trucks. Running on 24 volts, it was wound with copper ribbon from a commutator bar through one slot, back...
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    The insulation on one of these DC motors is made...

    The insulation on one of these DC motors is made to withstand a couple hundred volts from either lead to ground. If you float the DC with ground being the midpoint, you should have no worries from...
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    You may think you are joking, but you are not. A...

    You may think you are joking, but you are not. A friend, whom I will only describe as being capable of filling in for Jim Rozen, put a mass spectrometer leak detector on EBAY. He got an immediate...
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    As is so often the case in these inquiries, the...

    As is so often the case in these inquiries, the size and shape as well as the pressure (negative re atmosphere) is necessary to make any sort of reasonable estimate. In a sense, there is no such...
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    I have worked on lots of them, beginning in 1951...

    I have worked on lots of them, beginning in 1951 when I got a summer job in the P. E. Chapman Electrical Works at 1820 Choteau in St. Louis. I got a basic education, really basic. Penrose Embry...
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    The armature has more commutator bars than slots,...

    The armature has more commutator bars than slots, so it has some form of multiplex winding, which is used to give more smaller increments to torque. If convenient, see if the brushes are exactly 180...
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    If you have an open 0 point, you will have 370...

    If you have an open 0 point, you will have 370 open circuit volts to ground, but as soon as the motor draws current, the inductance of the transformer will reduce the voltage so there is no problem....
  9. OT-Has anyone made an automatic brick laying machine?

    Looking at a tall brick building and contemplating working on one way up in the air, I wondered if anyone had automated the process. It doesn't seem like it would be too hard to do. Of course, the...
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    I have no idea what your code says, but I think...

    I have no idea what your code says, but I think that the fuse in the 380 line would give reasonable protection to the other two. Typically, instruments that might have a half dozen voltages from one...
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    It depends on how much current total the items...

    It depends on how much current total the items use. What you propose certainly will work if there is enough capacity, but a 100 VA transformer is not very big. You would use about a 1/3 amp fuse in...
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    Just what I need. I have had to calibrate a...

    Just what I need. I have had to calibrate a couple of digital panel meters on VFDs to read in RPM. First I had to calibrate my strobe light, get the speed adjusted to an even number and then adjust a...
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    I haven't been watching the thread in the past....

    I haven't been watching the thread in the past. [I] looked at the opening and scrolled down to the pictures, and saw the connections. I should have read more instead of just glancing at the many...
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    As always a lot of sturm und drang over a simple...

    As always a lot of sturm und drang over a simple problem. In the picture of the connections there are two wires with push on connectors, pink and blue (sort of). reverse them and the motor will start...
  15. I agree. A friend works in a shop that has a Kent...

    I agree. A friend works in a shop that has a Kent grinder identical to mine. He says the nut holding the hub on the shaft is chewed up, rounded corners, from beating on a wrench. Mine is almost in...
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    My Sheldon came without a motor because it was...

    My Sheldon came without a motor because it was originally intended to be a demo with a variable drive but they went out of the manual lathe business and soon, all business. I installed a 15 hp DC...
  17. Working with sensitive electronics, I have seen...

    Working with sensitive electronics, I have seen similar effects many times. One of the causes is having a common ground for a sensor and something that generates spikes. You can build up an amazing...
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    Place three posts in the ground at the points of...

    Place three posts in the ground at the points of an equilateral triangle with two on a horizontal line and one above the center of that line at the altitude of the triangle. Stand at the center of...
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    I have repeated the story as accurately as I...

    I have repeated the story as accurately as I could, told to me in the first person by the victim. He was generally pretty honest but I think not above adjusting a tale a bit.

    In any case, it...
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    A company I worked for had a holiday and overtime...

    A company I worked for had a holiday and overtime pay policy that to get it you had to clock in on or before starting time and clock out on or after quitting time. One labor day a co-worker went to...
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    I said that the output of thyratrons was pulses,...

    I said that the output of thyratrons was pulses, but the SCRs have even more harmonic content and by firing more consistently make the pulsation even more apparent. An inductor is the way to go since...
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    I agree with the others about recutting the...

    I agree with the others about recutting the commutator. I like to install the commutator end bearing and chuck the other end, then hold the bearing in a steady rest set just tight enough to hold the...
  23. Thread: measuring runout

    by 9100
    Replies
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    3,436

    That is a decision you can make for yourself, but...

    That is a decision you can make for yourself, but this link lists applications where the spindle is held centered when it is motionless, not depending on the oil wedge. It will still move off center...
  24. Thread: measuring runout

    by 9100
    Replies
    46
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    3,436

    stong(Noun) An area of land equivalent to a...

    stong(Noun) An area of land equivalent to a quarter of an acre.

    John Strong (noun) a PHD who wrote the book on experimental physics.

    I have seen his name given as Stong, probably just a typo....
  25. Thread: measuring runout

    by 9100
    Replies
    46
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    3,436

    Here is an interesting (to me) article. Scroll...

    Here is an interesting (to me) article. Scroll down to page 29 for some comments about bearings.
    ...
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