I find it helpful, for purposes of sanity, to form a mental image of what could be happening in a given situation. It often doesn't matter if the image is scientifically or technically accurate, just that it make sense to the individual (me). So, for _my_ images of the Teflon bushings: First generation small bushings -- whatever happens to the wood affects (effects?) the Teflon bushing (back to Keith M's original statement). The resulting out-of-round of the bushing hole means that the center pin might just as well be held in a bench vise as a bushing surface. Any clicking is between the wood and the bushing once the Teflon goes ballistic, ah, egg-shaped -- the center pin is out of the circuit for my mental processes. Second generation small bushings (w/ribbing) -- ribs would help grip the bushing in the wood, possibly provide less wood to bushing clicking, but overall results same as first generation -- any change, and the center pin becomes captive. Third generation larger bushings w/ribbing -- all this time the center pins are the same, i.e., the only 'constant'. Therefore the hole for the center pin remains the same. So, in addition to the rib gripping characteristics in the wood, the larger overall diameter provide just enough surface flex on the ribs to act as shock absorbers. This provides a better chance for the pinned area to remain not only round, but more impervious to subtle changes in the immediate vicinity -- the ribs themselves do the give and take, not the hole. Another thought. I can't remember the action maker who used the brass ring around the Teflon, but it occurs to me that this would force the bushing -- as seen by the center pin -- to remain 'round' rather than becoming distorted. What it does (or did) for the bushing to wood clicking I don't know... I've never had any experience with these actions. This also adds support to those who have retro-added [whatever] to seal the wood at the bushing hole -- the sealer effectively becomes the "brass ring". I think I just agreed with Del, but instead may have written myself into a corner! Next!! At 07:51 PM 3/9/99 -0800, you wrote: >Probably just because of their size. The ribs might help, but remember that >the second version of small bushings also had ribs. Teflon does have some give >to it -- i.e., it's not a 100% rigid material. I think the extra diameter simply >gave the bushing room enough to absorb the slight wood movement. > >Del Jim Harvey, RPT Greenwood, SC harvey@greenwood.net ________________________ -- someone who's been in the field too long.
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