I recently purchased Aladdin's Castle (Bally, 1976) and have an issue with the flippers. While the left flipper stays tight, the right two flippers (tandem) keep working loose, especially the bottom flipper. I've replaced the flipper shafts - the originals were very chewed up by the knurled cup on the set screw. But that only worked temporarily.

I saw in some previous posts the theory that it is the crank that is at fault. That the metal in the crank is softer than that in the screws and by continually re-tightening the set screws, it causes the threads inside the crank to strip. Is that true? Has anyone else had a similar issue?

FYI - I've tried locktite on the screws and they still worked their way loose after 10-12 games. Does that add even more evidence to it being a crank issue?

Thanks!

Yes, two set screws per crank and using an allen wrench to tighten. There's no problem getting them tight. And they will hold the flipper fine...for a while. But eventually the flipper loses power - sometimes only swings half way. I tighten the screws again and everything's good, for a dozen games, then same thing. So I'm pretty sure the problem is either with the screws or the crank.

The pawls (cranks) are original, as far as I know. (I've only had it a few months.)

I saw this posted on similar topic, which is what got me thinking it was the crank: "The flipper crank is made of softer metal than the set screw. Tightening the set screw strips out the threads in the crank. Very common with early Bally. Replace the crank and set screw. If you haven't already rebuilt the flippers, you probably have worn bushings, weak springs and worn out EOS switches. Order the flipper kit from Pinball Resource, Marco or whoever. "

SirScott - yes, I did make sure to let it set for 24 hours before playing.

I didn't reply to vid1900's post - wasn't sure what he meant by checking for "play" in the threads. But after thinking a bit, I did re-insert the set screw about half way into each screw hole. One was rock solid - no movement at all. But the second one had quite a bit of "play" in it - screw wiggled up and down.

I believe that gives me the answer! Thanks everyone for your help, especially vid1900 and HowardR.

One last question: So now I'm torn between simply replacing the cranks ($10/each) and buying the complete rebuild set for 2 flippers ($50). Am I better off paying the extra $30 and rebuilding those two right flippers, rather than simply fixing the current problem?

Thank you, Vid! Greatly appreciated!

Update: So I just finished rebuilding the bottom right flipper using the kit from Marco. No problems with the rebuilding. Only major difference is that the set screws are about half the length of the previous ones, so it pretty much disappears into the crank, but it's still grabbing the flipper shaft without problem. But after one of two games, the damn screws work loose again. I'm now using a brand new crank and brand news screws made for it.

Is this a common problem with Bally flippers from this era (1975-1980)? Is there any way to keep the set screws tight? I'm going to try locktite again; hopefully that will hold it. But does everyone who owns Bally games from this era have to use locktite to keep the set screws secure?

Yes, allen type screws. I bought the game in January. Bottom right started flopping a couple days after I bought it. The guy who sold it suggested the set screws might be loose, even suggested swapping out the shafts. I was a total newbie at that point, so I simply retightened the screws and it held for 10-12 games, then started getting loose again.

I pulled out the shaft and saw it was all chewed up from the screws. So I bought a new shaft, inserted it and tightened the screws again. Same thing - held for a day or two, then loosened. Tried locktite; it held for about a week, then screws loosened again. Noticed on the forum that someone suggested problem was the crank/pawl, so I decided to do the rebuild. Using brand new crank and screws, and even put a brand new shaft in. Instead of getting better, it's getting worse. Screws are loosening after a game or two.

Haven't had any issues with the left flipper and I used locktite on the top right flipper a month ago and that one is holding tight. But the bottom right flipper - even rebuilt - is still a problem.

Here are some photos. The old set screws that came with the game are almost 50% longer than the new ones that came with the Marco rebuild kit. I'm not sure if this makes any difference since the screws still touch the flipper shaft. And they both have the knurled top, which I guess was designed to dig into the metal of the shaft and hold it in place...?

I also saw this in another thread from four years ago: "I always replace the flipper set screws with new appropriately sized socket head cap screws. They are significantly harder than the originals and, with an Allen key, I'm always able to get them torqued properly the first time."

That got me to thinking that maybe the socket head cap screws are the way to go...? But why would they work better? I did not that Pinball Resource's flipper rebuild kit did include socket head cap screws (see photo).

Crank Set Screw Comp (resized).jpg

Crank Set Screw Comp2 (resized).jpg

Pinball resource kt-bflip-screws (resized).jpg

Yes, that's locktite residue in the threads of the old set screws. Unfortunately, it didn't hold on that one flipper.

Also, here's the original flipper shaft. Notice how chewed up it is at the bottom, where the knurled top of the set screws dug in. I bought new flipper shafts and used them with my rebuild. But the screws still didn't hold for long.

Flipper shaft (original) (resized).jpg

Is the point to try to dig the knurled top of the screw into the metal of the shaft?

I'll try it again, super tighten them and put some locktite on the threads.

Any other suggestions greatly appreciated!

Thanks - I'll give it a try!

Mitch, I did what you suggested - really tightened those screws down (cranked so hard I thought I was gonna break the allen key). And IT WORKED! Played about 20 games on it so far and no sign of the flipper loosening. I guess that was the trick. Thanks so much for your help!

Sorry, Cactus Jack - meant to thank you for your suggestion as well. Been playing it for a almost a week and no sign of it loosening. Much appreciated!