Yamaha out of tune

[Ron Nossaman]

et al here,

>Roger, et al;
> This floating plate thing brings up a good question re: plate bolt
>tightening.
> What are the techs who insist on the efficacy of tightening plate
>bolts/screws on 'every' tuning going to do with these styles of suspensions?

*Not a bloomin' thing. Once the bolt head is snugged down on the plate,
trying to tighten it further won't do anything. In fact, you can back one
out a couple of turns without affecting much of anything if the plate to
bolt thread fit is decent. The bolt is threaded through both the plate and
the rim. As you turn the bolt, the height of the plate relative to the rim
can not change until the end of the bolt clears the rim. If the threads in
the plate are sloppy enough, it's possible that there could be some
movement, but snugging the head down on the plate will take care of that.
That was done once at the factory, and I seriously doubt that it will ever
loosen enough to need tightened. Regular lags, slip fit through the plate
and threaded into the wood, will loosen somewhat with time because of wood
movement with humidity changes. This doesn't happen with the floating plate
system because the bolt is locked to the plate by the threads and the bolt
head. Hope that makes sense. 

    


>  Won't the same factors leading to loose plate bolts/screws on conventional
>designs apply to the newer systems? For instance on Yamaha I believe that the
>machine screw is threaded into a tapped lag bolt which is in turn run into the
>rim.  Won't the effect be the same on loosening with this system as on a more
>conventional system?

*Shouldn't. The machine screw locks the lag to the plate very much like the
Baldwin system, only by a little different method. The long term effect
should be similar because neither system is using the lag (or bolt) as a
clamp to hold the plate down to plate supports. You shouldn't have to worry
about tightening them but if you try, it won't cause the subsequent damage
to the plate supports with the next humidity increase like it will with
conventional mounting systems. I hope all this makes sense. Sometimes the
picture in my head doesn't make it through my intermittantly faulty language
and concept processor andinto thetextin anysortofformatthatmakessense.


> Just a puzzlement...........
>Jim Bryant (FL)
>

Are we having fun yet?
 Ron