Bally Flipper Arm Grub Screw Size?

[Nedreud]

UPDATED
I finally discovered that the correct size is 1/8-inch! My cheap imperial Allen keys were just crap.

I'm trying to replace a flipper on my Bally VECTOR but I can't get the two ruddy grub screws undone that hold the crank arm on the shaft!

My main problem is I don't seem to have a tool with a really good fit even though I have a 30-piece Metric and Imperial Allen key set, and loads of other assorted hex shaped bits. 4.5mm is too large and although 4mm seems a good fit it eventually spins with enough effort. 7.64" is too small and 1/8" looks like it should be right but mine just won't fit. Grrrrr!

So, anyone know exactly what size I need to undo these little buggers so I can order The Right Tool For The Job?

 

[Poibug]

I do not know what the older ballys would be but,a few pins use 9/64"
If your 1/8 is too small it will be this
NEARLY all pins will be imperial,not metric

Friction drops are great for helping get grip on rounded off screws of any kind

 

[RudeDogg1]

Friction drops?

 

[Poibug]

kinda like valve grinding paste
tho,just occured to me certain toothpaste would sorta do the same thing,and the pin would be minty fresh

 

[Poibug]

http://www.screwgrab.com/

use that stuff in work - great!!

 

[Poibug]

http://www.ebay.co.uk/itm/Todays-to...438?pt=LH_DefaultDomain_3&hash=item19d2af16f6

 

[RudeDogg1]

Never heard of it would of been handy a few times

 

[replicas]

Never heard of it would of been handy a few times

So now you know for the future.

 

[RudeDogg1]

Indeed

 

[cooldan]

Nice one Poi, purchased

 

[Nedreud]

Friction drops?

That's exactly what I thought!

http://www.ebay.co.uk/itm/Todays-to...438?pt=LH_DefaultDomain_3&hash=item19d2af16f6

Thanks, @TYHO, I'll be getting some of those too.

Last night I popped round to see my neighbour. He's an audio sound engineer, so like me, his workshop is stuffed full of tools and gizmos. We went through all his Allen keys and bit sets, but nothing fitted. Admittedly almost everything he had was metric, but he did have the same cheap Allen key set as me which did have inch keys but none were right. As Poi pointed out, pinballs being a US thing everything's going to be imperial/inches.

But then he remembered he had a set of high-quality obscure security bits. You know, special Torx bits with holes in and stuff. And in there was an 1/8-inch hex bit with centre hole. The centre hole doesn't matter and it fits perfectly. Just a firm push to get it bedded right in and no sloppy play.



30 seconds later out comes my flipper and in goes the correct EM-style "FLIPPER"-embossed 2-inch mini-flipper on the upper-playfield of my Vector:



Sweet! I also replaced the sheared bolt on the coil stop bracket and fixed the missing plastic spacer in the EOS switch that meant the high current coil circuit was ALWAYS ON when holding up the main left flipper! Thought I might as well tighten all the nuts on the flippers as several were loose and I'd noticed the coil seemed rather loose on the main right flipper. That's when I spotted this:



The coil end stop bracket has sheared clean in half across the bend!

 

[replicas]

I take it you will be getting a 1/8 hex bit then for your tool kit.