swedging rotors

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dsfinley
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swedging rotors

Post by dsfinley »

What does it mean to swedge the rotors on your horn?
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burningchrome
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Re: swedging rotors

Post by burningchrome »

Hopefully make them fit better. If you valves are noisy, i.e. clacking, there is either too much clearance side to side on the spindel of the rotor or too much up and down between the rotor and the bearing plate.
Swedging is squeezing valve casing and bearing plate where the spindel passes through. Of course, if you swedge it too much, the valve will seize.
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Dan Schultz
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Re: swedging rotors

Post by Dan Schultz »

Rotor dynamics are a total departure from piston valves. The periphery of the rotor is not supposed to touch the inside of the casing. Rotors are suspended inside the casing by a radial bearing on each end and a small thrust area on each end. The small area between the rotor and the casing is sealed with a layer of moisture. A rotor will begin to drag on the inside of the casing when the little bearings on the ends begin to wear. Those bearings can be swedged down to the size of the worn spindles... hopefully still centered so the outer surface of the rotor won't drag on the inside of the casing.
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Roger Lewis
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Re: swedging rotors

Post by Roger Lewis »

If you keep your rotors well oiled and maintained, you may never have to have this done. My Cerveny piggy is about 40 years old and was played hard for 25+ of those years and has never needed this done. The valves are as fast and quiet today as they were when it was new. I'm pretty OCD when it comes to taking care of my horns. If you need information on how to keep your valves properly maintained, check out Jeff Funderburk's website which has all kinds of valve maintenance tips on it: http://www.uni.edu/drfun/repair_video/r ... index.html" target="_blank

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Dan Schultz
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Re: swedging rotors

Post by Dan Schultz »

Roger Lewis wrote:If you keep your rotors well oiled and maintained, you may never have to have this done. .... Roger
+1,000!
Dan Schultz
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Current 'stable'... Rudolf Meinl 5/4, Marzan (by Willson) euph, King 2341, Alphorn, and other strange stuff.
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