Hi Phil. Since we seem to need to get this most central point clear before we can go further, lets get this down first :) Positive bearing at all points on the bridge says just that. If you draw a straight line from the highest point on the bridge down to the front termination, then any point on the bridge that lies under this line is in a state of negative bearing. Same thing really going from the back side of the bridge to the hitch pin. Negative bearing is ALSO found when the whole bridge itself is below the string line... but then ... well.. there is no <<highest point on the bridge>> per se as its all under the string line. This is central to the whole line of reasoning that Rons <<theory>> rests on. If there is positive bearing at all points on the bridge, and strings need seating, then Rons claims do no not hold. Most certainly string seating is indeed a far more then temporary fix in this case and most certainly called for. It doesnt exhasperate the condition any more then is neccessary and expectable given normal life spans and useage patterns for instruments... I mean hey.. hammers wear with use too :).... Remember... Ron is not simply pointing out that the clamped condition of the strings are partially the cause indentation of the bridge in the face of upward pressure on the strings by the bridge. This is very old news indeed. He has claimed that whenever the strings <<need seating>> it is because this indentation has become so severe as to represent negative bearing at the notch...or over the whole bridge. Or it is because the soundboard has collapsed and is in a state of absolute negative bearing. Until a couple days ago, he also claimed that the dynamics of the system prevented any conditon where string seating was needed in the case where said negative bearing was not evident. And all this in turn has been used to tout the basic futileness of string seating in all instances. We cant recommend to folks that they not seat strings based on this. The only time string seating is in any meaningfull sense of the phrase <<a temporary fix>> is when there is indeed negative bearing at some point(s)on the bridge. And clearly.. this is not always the case. Cheers RicB Phil writes As I mentioned in a previous post I think we need some clarification of the terms bearing and contact. If the string is making contact with the bridge behind the crushed notch edge and is coming off the bridge at a down angle, I call that positive bearing with no contact at the notch edge. Are you calling this situation negative bearing? What are you calling positive bearing? Contact at the notch edge? Phil F ---------
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