Service Bulltein for Bally Linear Flippers

[Nedreud]

My new 1982 Vector has the re-designed Bally Linear Flippers (unlike my '79 Paragon that has the original style). Now I know these tend to cause heated debate on-line between the Don't-Replace-Purists and the Linear-Flippers-Are-Rubbish camps and I'm not here to start World War 3.

But what I have seen in several discussions is mention of a Bally Service Bulletin for linear flippers, but I can't find it anywhere and no one mentions that exact details. It seems it was considered that this design might have a weak return occasionally leading to sticking. There's much debate about magnetised end-stops, but the Service Bullentin suggests to cut the return spring in half.

Now, what else needs to be done? Should the spring be stretched out? And why would this improve matters? And, does anyone have a copy of the original SB that they could scan?

Here's what I think is an unmodified linear flipper, with an expanding return spring mounted between the switch bracket and short arm on the flipper pawl:


From: http://pin-logic.com/black_bally_buttons.htm

Is this the spring that the bulletin suggests to shorten?

Here's a different modified flipper by Pinside.com user @cubadee. Notice the expansion spring has been removed and replaced with a traditional compression return spring on the plunger (they also added an extra sprung leaf in the EOS switch to provide more force):


From: http://pinside.com/pinball/forum/topic/bally-linear-flipper-modification#post-751878

 

[Moonraker]

It seems it was considered that this design might have a weak return occasionally leading to sticking. There's much debate about magnetised end-stops, but the Service Bullentin suggests to cut the return spring in half.

Now, what else needs to be done? Should the spring be stretched out? And why would this improve matters?

Why not just buy a shorter return spring? They probably weren't available or someone was being lazy suggesting to cut the spring. If you do cut the spring do NOT stretch it out otherwise that would nullify the reason for cutting it in the first place (the need for a shorter=tighter return spring). Why? - stronger return leading to less chance of it sticking particularly if magnetised end stops are a problem. I did see a magnetised end stop being fixed by replacing the end stop itself but that may not always be the answer as every sticky flipper has a different story/cause.

 

[lukewells]

Don't forget that a stronger return spring would result in less flipper power, you would need to ensure to get the ballance right.

I have 4 games with the linear flippers. On the ones I have worked on, I have pretty much just done the standard mini rebuild kit (from Pinball Mania) and they have worked great afterwards!

I have a problem with the upper flipper sticking on Strange Science, but that seems to be because the pawl is excessively worn, so I imagine when I replace that it will be as good as new

 

[Nedreud]

... stronger return spring would result in less flipper power ...

That's what I thought. I guess it's a balance between enough oomph to return the mechanism quickly when the power is released but not too much to waste energy when coil is engaged.

I don't have any specific problems with the linear flippers on Vector. Maybe the main lower-right flipper is a bit weak as it's a bitch to make the "Vectorscan" shot up the left ramp with any real speed whereas the lower-left flipper seems to smash the ball into the H-Y-P-E spots or air the ball up to the X-Y-Z area. I'm sure a little mini-service of cleaning and buffing, and a new coil sleeve will improve matters.

Mostly I was just interested to see the the contents of the original service bulletin. Anyone have any idea what the release number was?

 

[kevlar]

Why am I digging up this old thread? After much head scratching I've come to the conclusion that my Centaur flippers have magnetic end stops :-(. I just googled " bally flippers magnetised " and this was the top result . Time for a rebuild.

 

[Nedreud]

I'm famous!

I've wondered about this magnetised end-stop business. Most of the end stops I've got seem to have brass (or what at least appears to be brassy or coppery, that is, obviously not steel) end-stops on them with the bracket being steel. Brass isn't magnetic. Maybe this fact, coupled with it's relative softness, is why it's used for end-stops. Also, on my GOLD BALL the brackets themselves are copper coloured so may not be steel either. One of them had snapped in half along the fold so obviously not too tough. If this was some non-ferrous copper alloy it would also be non-magnetic.

Like these:

http://www.marcospecialties.com/pinball-parts/A-613-67


http://www.marcospecialties.com/pinball-parts/A-613-127

 

[Nedreud]

Time for a rebuild.

A rebuild is likely to solve 99% of yours problems. Even just popping in a new coil sleeve and giving the plunger a good polish will make things much better. If you can take the time to strip and polish more of the assembly then all the better.

 

[kevlar]

Why should this particularly affect old Ballys though? They are all just a coil/plunger/endstop. Why did Bally have to mess around with non magnetic materials and other designs don't suffer?

 

[Moonraker]

It's not just an old Bally issue, there were several WPC machines suffering magnetic end stops at last years EPC in Italy.

 

[kevlar]

Cheers guys. Reading Pinside there are quite a few people hate these linear flippers!.

 

[ronsplooter]

Reading Pinside there are quite a few people hate these linear flippers

Reading Pinside they're are quite a few people who hate everything I love the feel of old Bally flippers, they're awesome

 

[kevlar]

Reading Pinside they're are quite a few people who hate everything

Good point !