Alex C wrote:I did use valve oil for lubrication but the main "difficulty" I experienced was with the adjustment screw. Though I rarely adjusted them, they eventually stripped. I also got binding in a couple of instances; replacing the Du-bro fixed the problem. I would encourage this exchange for many people but in most of my playing venues I don't need to be worrying about mechanical (real or imagined) issues.
I didn't mean to indicate that the Du-bro is a bad replacement but the all-metal uniballs are more likely to be "lifetime" fix.
I suppose that depends on whose lifetime. Maybe you are practicing too much, heh, heh. Like I said, I have conversions going back 20 years that continue to work perfectly, but even in the case of professional use, they are probably not being used four hours a day.
I would really like to study your installation and the failed ball joints (I realize they are probably long-since in the trash), because I recommend these things and there may be a situation to avoid. And my engineering brain demands an explanation, heh, heh.
All-metal uniballs are just as likely to wear if the oil is inadequate--perhaps even moreso. And they are not adjustable, harder to fix in the field, heavier, and much more costly. Make sure you keep them lubed with something a bit thicker than valve oil. I use the same oil that I use for the rotor bearings--a light machine oil of the 3in1 variety, or the Hetman equivalent (Hetman has that lovely needle-point applicator bottle that lets me point one drop right where it needs to go).
Rick "who agrees that the objective is to remove the issue from conscious thought" Denney