Multi stage flippers on BK2K?

I am finishing up my restoration on BK2K and I want to add multi stage flipping (press button further for upper flipper, lower fires first but upper doesn't have to)

I bought the multi stage switch stack, and I just need to make sure I understand how the flippers in BK2K work before I wire it up and it explodes.

As far as I can tell since I sadly cannot read schematics (need more electronics classes) :

the lower flipper has a switch in the EOS stack that provides power to the upper flipper?

The flipper button provides the ground to finish both flipper circuits on separate wires?

If these are both true, could one not remove the power switch, making a permanent connection, and use a multi stage flipper button stack to complete both circuits at separate times as desired? Would powering the upper flipper at all times cause problems? Most flippers always have power right? I've never heard of one that works like this.

FJIMG_20180720_163338 (resized).jpg

#2 5 years ago

ZAC

zacaj

Looking at the cabinet schematics, it shows two flipper contacts in the cabinet on the flipper. Yours only has one? I thought every 80s williams supported staging

The power wiring disagrees though... hrm

To adapt it to staged, bypassing the secondary switch on the lower flipper mech and redirecting the black-yellow wire going to the cabinet flipper button to your new one should be enough.

#3 5 years ago

RMM

McSquid

Pinside member

Correct, I have 2 wires in the cabinet, but they are hooked up to the same switch.

Then there is an extra switch in the EOS stack that I have read provides power to the upper flipper.

FJIMG_20180720_165703 (resized).jpg

FJIMG_20180720_165729 (resized).jpg

#4 5 years ago

ZAC

zacaj

connect the two lugs on that switch together, separate those two wires on the cab switch out, and it should work. It'd be best to add another 0.1uF, 500V capacitor across the secondary contact on the cabinet switch too.

#5 5 years ago

RMM

McSquid

Pinside member

That's exactly what I thought would work, just wanted to check to make sure there wasn't some reason Williams switched the power to the upper flipper.

#6 5 years ago

ZAC

zacaj

OP
Quoted from McSquid:
That's exactly what I thought would work, just wanted to check to make sure there wasn't some reason Williams switched the power to the upper flipper.

I mean, there may be? Having the two different color wires running down there, and part of the manual referencing staged flippers still, makes me wonder if they took it out last minute for some reason. Your logic all seems good to me though, I'd give it a shot and see

#7 5 years ago

RMM

McSquid

Pinside member

Ok, gonna give it a shot, still some time before I'll be ready to power it up and test. If anyone knows a reason I shouldn't do this, please chime in in the meantime.

#8 5 years ago

FNG

DumbAss

Pinside+ Frequent

9y 109K 2,982

I believe the factory wiring was done to provide maximum power to the lower right flipper (for the power stroke). The thought was the flipper needs maximum power to get the ball up the ramp to the upper playfield. Once the power stroke has completed (the EOS opens and the stacked switch closes) power can be provided to the upper right flipper.

I have done this modification to my BK2K and have noticed no problem with the lower right flipper making it to the upper playfield. I like the double leaf switches for flipper control.

#9 5 years ago

RMM

McSquid

Pinside member

Thanks so much for weighing in. Im glad to have someone who has done it confirm the theory and operation.

1 week later

#10 5 years ago

RMM

McSquid

Pinside member

Update: works fine. Recommended.

8 months later

#11 5 years ago

SAA

shaub

Pinside member

9y 66,050 1,815 21

so im looking to do this but to make sure i understand what I'm doing and why.

so is that switch on the lower right flipper that activates the upper flipper basically a 2nd cabinet switch? so if I were to jumper the switch contacts, both flippers would activate simultaneously when the actual cabinet switch is pressed?

My understanding is that both right coils ultimately have the same 50v wire (blue-yellow) and both go to ground through the org-vio and then the cpu. (the upper flipper from blk-ylw and the lower flipper from from blu-vio.)

is that correct or do I not understand how the circuits work..

#12 5 years ago

ZAC

zacaj