Cleaning and Re-Rubbering Centaur
There's a first time for everything...and this was my first time taking apart a pinball machine and replacing the rubber rings. I've done it a few times since then (including the hairy mess of replacing the rubber on the much more complicated Addams Family playfield). But, the first time around, I actually documented the process.
Dust and grime accumulates on pinball machines. It gets all over the playfield. Most people would expect that in a 24-year-old machine like Centaur--and, indeed, you could see the dirt in this one when I bought it. Even if you can't see the dirt, it could be there. When I replaced the flipper on my Addams Family, I decided to wipe down.
the playfield while I was at it--and I ended up with one dirty towel when I was done. Moral of the story: clean your pinball machine regularly to prevent a build-up of nastiness that can affect play and, eventually, damage the playfield.
Centaur was dirty enough to warrant removing everything from the playefield to get to all of the hidden corners--and to clean the plastic parts, which were also covered with a thick layer of dust and grime. I browsed the pinball newsgroup and asked experienced collectors what to use for cleaning. I ended up using Wildcat 125 for the playfield itself, and Novus 1 for the plastic pieces (hereafter referred to as "plastics," the commonly-used term among pinball folks who are in the know). You need to use a very gentle cleaner on the plastics--Novus 1 seems to be the best choice out there. You can get both of these products at pinball parts dealers on the Internet, including Marco Specialties and Pinball Resource.
2020 Note: During my latest round of playfield cleaning, I did searched the newsgroups and talked to fellow hobbyists and found that what cleaning product is best for cleaning playfields is a matter of great debate. Nobody agrees on anything--apart from the fact that Wildcat 125 is out. After a while, I gave up and just used Novus 1 for both the plastics and the playfield. It's not abrasive, and it does a good job without leaving any residue. Just don't scrub so hard that you take the paint off and you're good.
I'm always hesitant about disassembling complex things with lots of parts--and a pinball machine playfield certainly fits that description. Prior to starting my cleaning project, I browsed the Web for tips. One was to take lots of pictures for reference prior to removing pieces, so I did. The second was to lay out the pieces on the playfield glass in the same arrangement that they appear on the playfield so you have a rough idea where everything goes. That turned out to be the best advice ever. I only had to refer to my pictures once. The rest was mapped out for me right there on the glass. Very cool trick! (See the picture gallery--I highly recommend this method.)
I removed all of the plastics and cleaned one section of the playfield at a time. Pour a little Wildcat on the towel, rub it in gently, buff the section with a clean towel. Repeat over and over again. As I completed a section, I replaced the rubber rings in that section--the bands that wrap around posts, are strung across slingshot targets, and so on. The dealer who sold me the machine included a rubber ring kit (a complete set of replacement rubber rings sized to match all of the existing rings on the machine). You can find kits for most machines at Marco Specialties and other online dealers--check the links page. These rings get really dirty, lose elasticity, and crack over time. When they start drying out, the also rubber flakes off and contributes to the dirt on the playfield. Replacing them makes a HUGE difference in how the machine plays. Some machines, Centaur included, originally used black rubber rings. Many people recommended white replacement rings instead, because black rings shed black residue that makes the playfield dirty. All of the rings are white now.
After the entire playfield had been cleaned, I began reassembly. As I was about to install each plastic piece, I cleaned it with Novus 1 and buffed it dry. What a difference! Although the yellowing that is common over time will never come out, the nasty film of dust and gunk disappeared, and the plastic is now shiny and much nicer looking. The biggest difference can be seen on the translucent red lane guides and bumper caps, which now sparkle like new. I hadn't realized how dirty they were!
Along with the playfield, I wiped down all of the metal trim and the sections that are covered (these sections--like the section under the metal apron at the bottom of the playfield, around the outhole--were filthy). I wiped down the tracks in the outhole as well to ensure that the balls didn't pick up more gunk and drag it onto my now-clean playfield.
Finally, with the machine reassembled, I inserted five brand new balls to replace the old scratched ones. Using scratched balls can damage the playfield. Besides, new balls are pretty cheap.
After it was reassembled, I was happy with the way the machine looked. I was a bit disappointed that the yellowing of the playfield art was unaffected by the cleaning. Apparently, the playfield was clear-coated at one time, and the mylar is yellowing. It's also not very clear in spots, most noticeably over the bonus light inserts, but it can't be removed without wrecking the artwork underneath, so I guess I'll have to live with it. Everything else was sparkly clean (and I keep it that way now). Plus, the new rubber and clean playfield took my high score from about 500,000 to over 2.5 million! Sweet!