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Rubber Grommets

Posted: Thu Feb 19, 2009 11:15 pm
by kiramdear
Pardon my dust, folks, but you know how jetglo is ... :oops:

My question is about the purpose and placement of these rubber rings on the height adjustment screws of the bridge of my 320. I'm guessing they may be there to deter rattling, but are mine correctly placed as you see them here?

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Re: Rubber Grommets

Posted: Fri Feb 20, 2009 12:50 am
by beatlefreak
None of mine have grommets on the bridge height adjustment screws. I don't think they're a RIC part.

Re: Rubber Grommets

Posted: Fri Feb 20, 2009 12:59 am
by deaconblues
My 325c64 has 'em. Rubber grommets were used before they put springs on the screws. Some of mine sit flush, some don't...I don't really think they do all that much, anyway. I would guess that the idea was to hold the screw roughly in place, so any location is probably fine as long as it's touching the sides.

Re: Rubber Grommets

Posted: Fri Feb 20, 2009 10:11 am
by jps
I usually keep them pushed down on the bridge bottom; I have them on the '67 4005WB and '67 330.

Re: Rubber Grommets

Posted: Fri Feb 20, 2009 10:27 am
by leftybass
They are a factory part, or were back in the day and on certain reissues. My 1964 360/12 has them.

Re: Rubber Grommets

Posted: Fri Feb 20, 2009 5:34 pm
by kiramdear
Right. My 320 is from August 1982, and the grommets were original, I'm sure, being the only owner.

Say, if you moved them just below the bridge, do you suppose they would act to keep the screws from backing out?

Re: Rubber Grommets

Posted: Fri Feb 20, 2009 8:11 pm
by jps
kiramdear wrote:Right. My 320 is from August 1982, and the grommets were original, I'm sure, being the only owner.

Say, if you moved them just below the bridge, do you suppose they would act to keep the screws from backing out?
Get a second set and do that with them.

Re: Rubber Grommets

Posted: Sat Feb 28, 2009 4:04 am
by 37012player
Consider a bar stool with just 3 legs.....stick with me here guys......it naturally sits nice and stable. Now think about a 4 legged stool....chances are that if either one leg is a tad longer or shorter it will want to rock about a bit. IU think we've all experienced this effect from time to time. The 3 legged stool has equal pressure on all its legs, not so the 4 legged stool.

With that in mind...Back to the Rick bridge..which is a 4 legged bar stool.

So, the grommets when pushed down to the base of the bridge chassis, will eliminate any rattle from one of the height adjustment screws if it is not under the same pressure as the other three, which naturally it will not be.

I've noted on some of my ricks with a low action that the modern springs are not long enough and need to be pulled out and stretched or...yep..they rattle too :)

Push your grommets down to the bottom! Hope this helps...

Si.......

Re: Rubber Grommets

Posted: Sat Feb 28, 2009 4:13 am
by kiramdear
After a couple of beers, they all rock under me regardless ... :lol: :lol:

But that's some pretty good figuring, Si. Makes good sense to me. :) That's one thing I check for often, and try to get them all even. But the chances of having them all equal are slim, I would guess, especially once you start to thrashing. Thanks for a good analysis :D

Re: Rubber Grommets

Posted: Sat Feb 28, 2009 4:38 am
by 37012player
Kira,

Yep I have the same problem with beer....OOops did I say problem..hic!

For what its worth, I believe the grommets are a better solution to the problem than the springs. The rubber has better dampening characteristics than the metallic springs in my experience vintage versus modern. I change the springs out for the grommets now.

It's Saturday night here....Beer O'Clock??? :D

Si.......

Re: Rubber Grommets

Posted: Sun Mar 01, 2009 2:33 pm
by Woodie
The factory name for these is/was Bun-O-Rings. Back in the day, bridges also had nuts on the height adjustment screws underneath the bridge. Still have some of these in my parts drawer.

Re: Rubber Grommets

Posted: Sun Mar 01, 2009 2:38 pm
by kiramdear
That follows my thinking about the grommets doing some good on the underside of the plate. It makes sense to try to prevent the screws from backing out due to vibration. That's interesting, Alan. Thanks for posting. :)

Re: Rubber Grommets

Posted: Sun Mar 01, 2009 7:54 pm
by Woodie
You're welcome, Kira. Glad to help.

Re: Rubber Grommets

Posted: Sat Mar 07, 2009 4:33 am
by 37012player
Woodie wrote:The factory name for these is/was Bun-O-Rings. Back in the day, bridges also had nuts on the height adjustment screws underneath the bridge. Still have some of these in my parts drawer.
I've never notice this.. Do you have any pics of this set-up?

Si.................

Re: Rubber Grommets

Posted: Wed Aug 11, 2010 7:47 pm
by stringman
rubber bridge grommits standard on 360 WBs and early style bridges. My guess, for the purpose of dampening the rattling of the height screws.And yes they are set from the factory at the top of the screw.