The ball joints I use have screws to adjust the tension, but the screws should really be used just to take up most of the slack and no more.TubaTodd wrote:I believe the Hirsbrunner I spoke of had homemade style linkage a la "Rick Denney". With that kind of linkage there is no screw to adjust.
Miraphones have screws in the back caps that can be used to take up thrust wear, but this is a stop-gap until a proper repair can be done.
Yes, valves should spin freely, but not like a top, unless you use a very light oil (like valve oil). And such a light oil will not do a good job of preventing wear. Oil for rotor shafts should be about the thickness of light machine oil, which is still light but heavier than valve oil. It will damp the spinning a bit. The important thing is that while there may be damping, there is no mechanical drag from buildup around the rotor bodies or from the rear plate being misaligned when it was reinstalled. You'll know it when it's right.
The typical springs used these days are not adjustible, but they may be wound too tightly. When you reassemble, the spring only needs to be wound just enough to move the valve through it's travel. Making springs tight to overcome friction that shouldn't be there is the wrong solution.
Rick "who thinks pistons have their issues, too" Denney
