Is it possible to reverse the rotation of a radial saw motor?

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On Tue, 20 Jan 2009 15:24:09 -0500, Andrew Erickson

That's the way I understand it and I won't quibble on whether it's 60 or 120 time/sec. Kinda depends on the definition of "reversing". So "reversing polarity" of the brushes - which I interpret to mean switching leads - won't have any effect on rotation direction of a universal or any other type of AC motor. That would be no different than reversing the plug in the wall socket.
On the other hand, breaking the motor open, and doing some internal rewiring might accomplish the mission.
Tom Veatch Wichita, KS USA
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Switching the leads to the brushes generally does require breaking the motor open and rewiring it internally a bit. It's not the same as reversing the plug in the wall socket (which, as you correctly observe, would have no effect on the direction of rotation). Swapping the input leads changes both the field (stator) and the rotor, and so the rotation stays the same. Swapping the brush leads changes only the rotor, but leaves the field unchanged, so the relationship between them is reversed.
Here's the a link to a quick schematic sketch of this operation on a series wound motor that might make things a bit clearer:
http://users.gmavt.net/drewe/pix/misc/Motor.png
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What I intended was to swap the wires to the two brushes (this is easy to describe, there are other rewirings that would accomplish the same thing). Because the brushes activate the ROTOR magnetization, the swap would reverse the rotor poles without changing the other magnetic part, the STATOR. That accomplishes the reversal of a brush-type (universal) motor.
Think of the (temporary N) pole on the rotor, pulled clockwise; if you make it instead a (temporary S) pole, the attraction becomes repulsion and the motor goes counterclockwise.
Swapping the wall socket polarity would reverse both rotor and stator fields, so has no effect on rotation direction.
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If it is a single phase motor it won't reverse.
Think about all those two prong corded ac 115 VAC tools......
You can reverse rotation on a three phase mpotor but as the other folks said, why?

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If you reverse the rotation, doesn't it reattach the piece you cut off?
Puckdropper
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On Thu, 22 Jan 2009 00:38:04 GMT, "Jay Giuliani"

You most certainly CAN reverse a single phase motor. On some motors the connections are brought out to make it simple, on others you would need to dig a bit.
My lathe has a 1 HP single phase cap start motor that can be started in either direction.
Almost any single phase induction motor will run backwards if spun fast enough backwards before power is applied
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