Pretty new to the hobby, but having grown up in my younger years playing classical music where I spent a lot of time around xylophones and glockenspiels, I was really excited to try to improve the sound on my 1976 Williams Space Odyssey chimes. I have had a few conversations with friends who are percussionists about this to get feedback on what the supports for different instruments (vibraphones, marimbas, xylophones, etc.) are constructed of.
When I purchased the table last spring, the chime unit was in really bad shape (go figure). The smallest chime did not sound at all because the the plunger was frozen in the bell sleeve. The other two sounded extremely "tinny" as musicians would say and lacked any real resonance. The shock mounts that held the bars off the chime posts were pretty much rotted away and there were little brittle parts of them stuck on the posts and lots down in the chime box itself. The two bars that actually worked just kind of clanked when struck. It was bad.
First I disassembled the unit and cleaned everything that needed it in the ultrasonic. Then I used Mother's Mag and Aluminum polish on the chime bars. They came out great. I purchased a chime rebuild kit from Steve at Pinball Resource and used it to replace all the old battered parts. Swapped out the 3 long bell coil sleeves and re-polished the plungers so they moved freely. Once all this was done, I was much happier with the sound but it was still not there.
The biggest issue is that the longest chime bar (I'd safely assume this is true across the board on Williams 3-bar chimes of the era) is "heavy" to the point that it will not resonate as well as the other two. The weight of the chime bar simply means that it rests heavier on the shock mounts which tend to deaden the resonance. I have purchased a bunch of different washers of different shapes and sizes since I re-built the unit and at some point I'm sure I will find a configuration that best supports the chime bar while giving it the freedom to vibrate for as long as possible, which is what will reduce or remove the clanking. It is not nearly as bad as it was when I bought the table, but it is still not where I want it. If I get a chance this weekend I will swap a few in and out to see if I find what I'm looking for and I'll let you guys know.
To be honest, one of my plungers does not have nylon on its tip. It just has a piece of pencil cut and glued into place. This might anger some purists, but the wooden tipped plunger sounds very good when striking the chime bar. It's simple, really. The wood contributes a less harsh tone to the sound than the usual piece of hard nylon. It's the same reason many percussion mallets use rubber or rubber bands or felt on their strikers. Anyway, I'll keep you all posted on my progress as I work through this. I know it may seem wrong to some to leave the stock parts behind in the search for good chime tone, but I think it's kind of fun trying to get a good tone out of the Williams configuration.
I totally agree with CactusJack about Williams chime units being inferior. All I needed to do was play a few EMs from each manufacturer last spring at the time I was first working on the issue with my Williams table to confirm that there is a much better sound out of Gottlieb and Bally chime units. Bally units I love. They sound really deep and rich.