Posted by Rick Denney on December 19, 2001 at 10:13:13:
In Reply to: Re: Re: Meinl Weston 30 posted by David on December 19, 2001 at 09:50:33:
I agree that S linkages are quite durable when properly maintained. In most cases, however, we are buying used tubas where they haven't been maintained. In fact, as long as it has been since manufacturers have made S linkages, I'd bet that most of them on currently available used horns are already worn out as a result of poor maintenance by previous owners. And it is also true that many times the noise that is attributed to the linkages is really coming from loose rotor bushings.
But why would you suggest spending the large sums required to obtain Meinl-Weston ball-joint linkages instead of the parts available at hobby shops?
I've made conversions on perhaps half a dozen tubas using those model-shop ball ends, and every single conversion is still in like-new condition. And I made the conversions ranging from ten years ago to 15 years ago. If you wrap the threaded rod in a brass tube, they look just fine, and as good as most of the manufacturer offerings.
If it is fear about the plastic, then that is just silly. Plastic bearing surfaces work extremely well in situations that avoid high temperatures. Their adjustment is simplified because they are not too stiff, and they conform to the ball more readily than metal sockets. They work tolerably well even without lubrication, and the good ones will not beak down with lubrication. On the other hand, I have seen a variety of manufacturer ball-end arrangements that were worn out, all of which, it seems to me as an engineer, stemmed from their use of materials that they perceived would look better than the hobby-shop plastic. Examples from my own experience include the brass-on-brass linkages used by Cerveny/Amati and Musica in the 80's, and the white plastic ball ends used by Miraphone about that time.
And your total investment in parts for new linkages will be about $25 with the hobby-shop parts.
Rick "who will happily spend the money when needed, but who sees no need here" Denney