aja wrote:
How much do these designers really know about gear design?
Good question - I know little beyond how these things perform/feel for me, so would be interested in any info you have. The classical community seem to lean most to the Rodgers machines - and they are some of the more expensive ones, but they were the ones I liked the look of the least. The Alessi are also expensive, but opinions seem very divided and by all accounts they are inconsistent.
Klaus Scheller on the other hand is an engineer (and German ?). I love his use of bearings and the metal bushings through the posts.
For example, the root of the teeth on the worm wheel of those rodgers look like they are lacking any type of relief fillet - stress induced micro cracking just waiting to happen. And, it looks like he tried to use a gear ratio that is much too high for the given tooth module. Additionally, the top land of the worm looks very thin.
Then again, the pressures involved in a nylon string are relatively low (about 5 kgs per, IIRC), so I would presume that stress isn't a huge issue.