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  1. Replies
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    its the horizontal ram!

    its the horizontal ram!
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    disagree. static axial load that a standard...

    disagree. static axial load that a standard radial ball bearing can handle is half of the radial load.

    the problem is that its easy to put thousands of pounds of force on the bearing with a slide...
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    its visible but easier to see in this image...

    its visible but easier to see in this image
    https://www.applied.com/webmedia/product_assets/h9f/h94/9240870420510.png

    look at the widest part of the tooth at the pitch diameter and compare to the...
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    so this is effectively: not even a quill on a...

    so this is effectively: not even a quill on a drill press, but the horizontal ram. not a rack and pinion steering box for a vehicle.

    there is a discussion here about an 11 tooth gear that may be...
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    Any machine with a regenerative drive will...

    Any machine with a regenerative drive will probably need 3 phase and there is no way around it.
    Older machines which will have brake resistors on the dc drives and spindle should not need 3 phase....
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    laser cut a 12 tooth 2 modulus gear from 1/8"...

    laser cut a 12 tooth 2 modulus gear from 1/8" plywood and see if it fits your machine.

    if it does, try buying a 5$ 12 tooth 20mm wide 2 mod gear off of ebay and wait three weeks for it to get...
  7. I have had limited experience with two methods. ...

    I have had limited experience with two methods.

    first one was a standard car battery. it got to the point where couldn't keep the headlights on for 5 minutes or truck wouldn't start. Electrolyte...
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    that straight edge looks milled on both sides. ...

    that straight edge looks milled on both sides.
    find a 5" or 6" mike and measure the width of the straight edge every 2 inches.

    then set it on the surface plate and use an indicator to measure...
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    5 ohms on a 1kva 250v tx is 125 watts lost at...

    5 ohms on a 1kva 250v tx is 125 watts lost at full load just for the primary coil. A bit excessive.

    Did you make a 4 wire resistance measurement?

    Btw if you want i cam describe how to make an...
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    A 1 kw transformer 120v isolation tx should have...

    A 1 kw transformer 120v isolation tx should have more like .5 ohm coils. 10 amps at 120v would be 50 watts lost per coil, or 100 for the whole thing, which would be 10 volts drop under full load, or...
  11. Thinking about this more, the dovetail round post...

    Thinking about this more, the dovetail round post can be the nut, separate from the slightly concave disk. You dont need to start from solid and remove half a pound of steel.
  12. do yourself a favor and take a 2-3" diameter disk...

    do yourself a favor and take a 2-3" diameter disk of metal, about 1" thick, chuck it up and face it flat, then flip it around and turn it to the standard dimensions for the circular dovetail post...
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    The amp clamp meter value squared times the...

    The amp clamp meter value squared times the resistance of the transformer windings will not be accurate for total losses.

    It will accurately measure the copper losses in the primary but it will...
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    My experience with a ~70 pound load pressing on...

    My experience with a ~70 pound load pressing on about 6 square inches of white "formica" with oil grooves in a fractal pattern of nominally 1/4" square areas of contact riding on top of cast iron...
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    Buy a 120:120v isolation transformer from toroid...

    Buy a 120:120v isolation transformer from toroid dot com. Connect it as an auto transformer.
    Btw they actually sell 240/120v auto transformers which are not exactly 1:1 ratio to compensate for...
  16. if a ground ball screw is rusted to the point the...

    if a ground ball screw is rusted to the point the nut cant turn it is of no value to any situation where one would need a ground ball screw.

    if its a rolled ballscrew and looks like this well...
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    in some places you have 3 phase power in the form...

    in some places you have 3 phase power in the form of 2 phases of Y service but you don't know it.

    you can indeed hook up a 3 phase motor from line to line and line to netural, and you can...
  18. just use a generous amount of cement such that...

    just use a generous amount of cement such that there are no voids when you fit it together, then wipe off the excess.
  19. No JST, they are synchronous generators. the...

    No JST, they are synchronous generators. the rotor has a diode in series with its shorted winding, and it picks up power via the third harmonic. as such there has to be some third harmonic in the...
  20. I don't have any experience looking at the...

    I don't have any experience looking at the waveform of a large capacitor excited brushless generator head, but i can tell you that an AVR head is going to have a lower idle power consumption,...
  21. Many but not all hvac systems are power factor...

    Many but not all hvac systems are power factor corrected input and they should run off of anything above 40hz up to 320 volts. (Which rectifies to 450 volts). Above that voltage something may fail. ...
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    I acquired two of these battery chargers, one had...

    I acquired two of these battery chargers, one had blown up.

    Low-noise, high-power 12V battery chargers (adjustable 13.8 VDC, 15 to 90 amps) with 2 year warranty

    I have 2 of the 45 amp versions....
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    what i would do at this point is find the 6 wires...

    what i would do at this point is find the 6 wires that turn the igbts on, and disable them. desolder the pin from the board.

    then power it up and see if it still says sc fault.

    if not, then...
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    so chances are good that the 760 volts that was...

    so chances are good that the 760 volts that was produced on the dc bus when you powered it up at double the input voltage.. is not enough to blow everything up.

    but something failed, and you need...
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    the only way i can imagine you blew up a...

    the only way i can imagine you blew up a capacitor is to have incorrectly wired it such that you formed a voltage doubler and the capacitors exploded. in which case, you may need to replace all of...
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