Re: noisy miraphone valves


[ Follow Ups ] [ Post Followup ] [ TubeNet BBS ] [ FAQ ]

Posted by Joe S. on August 03, 2001 at 01:20:49:

In Reply to: noisy miraphone valves posted by ken k on August 02, 2001 at 23:16:51:

Regardless of the linkage, noise in Miraphone valve assemblies is usually due to worn rotor spindle bearings. If the rotors all pass the ol' "pop" test, these bearings can be swedged tighter and lapped in to a nice re-fit by an experienced and known-to-be-good repairguy. There is likely (besides left-and-right) some up-and-down play, too, AND THE UP-AND-DOWN play is USUALLY the noise culprit. To solve this, I remove the back bearing from a rotor, rig it on my lathe in some way as to not screw it up, and turn the INSIDE shoulder of the bearing down a bit...usually about .002"-.003" per "swipe" (followed by tests) until I've taken off just enough to let the rotor turn but prevent it from rattling vertically.

The cheesy way to fix this is household oil + turning in those center screws on the rotor caps as far in as they will turn and still allow the rotors to turn freely..."JUST" to that point...


Follow Ups: