Did you do anything to the pop bumpers to get them to rebound so strongly? They look like you may have converted them to DC voltage with a bridge rectifier.
Hi Joe. The old metal solenoid sleeves were replaced with nylon sleeves. Each pop bumper was taken each apart, cleaned thoroughly and reassembled. The inside of the solenoids was cleaned with a cotton swab and isopropyl alcohol to remove the black solenoid dust. No other new parts were used except for maybe some new #47 lamps. It took me about an hour to clean each pop bumper. I used 400 grit sandpaper to remove most of the 40 years of black crud on the solenoid plunger. I used fresh sandpaper to clean all contacts with particular attention to the two large contacts. I sanded these repeatedly to remove some of the pitting that occurs on these type of contacts. I then adjusted the contacts that activate the solenoid and connected to the skirts as closely together as possible. The contacts should be perfectly parallel to each other. I then used the 'fist test' to test if the contacts were too close together. A light pounding of my fist near the pop bumpers on the playfield should not activate any pop bumper. I then test by playing some pinball. If more than one pop bumper pops at the same time then I know to back off the contacts. As far as power goes, Williams didn't go with DC power to the pops and slings until 1972. So, as you already seem to know, Expo that was manufactured in 1969 does not have DC power and I have done no mods to add it. The transformer is set to high tap. I prefer to keep my EMs on normal tap but that is the way I received Expo and I haven't changed it. All the attention to detail payed off. Even on high tap, these pop bumpers barely bumped before the restoration. Now they play like they used to when Expo was new - almost good enough to make anyone seeing Expo in action believe that they are DC powered.
Hello John. Thanks for letting me know. The new link is www.pecospinball.com/my_first_full_pinball_restore.shtml Lots of good stuff in there. Expo is a fun game, hope you get it.
Nice work! Fun video!! Looks like a great game - hopefully my Gottlieb Sweet Hearts plays as well after restoration.
Did you do anything to the pop bumpers to get them to rebound so strongly? They look like you may have converted them to DC voltage with a bridge rectifier.
Hi Joe. The old metal solenoid sleeves were replaced with nylon sleeves. Each pop bumper was taken each apart, cleaned thoroughly and reassembled. The inside of the solenoids was cleaned with a cotton swab and isopropyl alcohol to remove the black solenoid dust. No other new parts were used except for maybe some new #47 lamps. It took me about an hour to clean each pop bumper.
I used 400 grit sandpaper to remove most of the 40 years of black crud on the solenoid plunger. I used fresh sandpaper to clean all contacts with particular attention to the two large contacts. I sanded these repeatedly to remove some of the pitting that occurs on these type of contacts. I then adjusted the contacts that activate the solenoid and connected to the skirts as closely together as possible. The contacts should be perfectly parallel to each other. I then used the 'fist test' to test if the contacts were too close together. A light pounding of my fist near the pop bumpers on the playfield should not activate any pop bumper. I then test by playing some pinball. If more than one pop bumper pops at the same time then I know to back off the contacts.
As far as power goes, Williams didn't go with DC power to the pops and slings until 1972. So, as you already seem to know, Expo that was manufactured in 1969 does not have DC power and I have done no mods to add it. The transformer is set to high tap. I prefer to keep my EMs on normal tap but that is the way I received Expo and I haven't changed it.
All the attention to detail payed off. Even on high tap, these pop bumpers barely bumped before the restoration. Now they play like they used to when Expo was new - almost good enough to make anyone seeing Expo in action believe that they are DC powered.
Hello John. Thanks for letting me know. The new link is www.pecospinball.com/my_first_full_pinball_restore.shtml
Lots of good stuff in there. Expo is a fun game, hope you get it.
Looks like the link at the bottom of the description no longer works.
I might be picking one of these up tomorrow! Do you have an updated link?
What a lazy design and theming.