What happened?

Oooooohhhhh, I thought there was a big ass gap under a bent ball guide! Guess that is paint (have not played ST yet). Easy fix, don't drain!

I put a thick vinyl over that area on mine and it seems to be holding up well.

Yeah you (we) could use one there.

I would of never thought of putting Mylar there.

Interesting.

I've asked Cliff about creating one for the center drain hole on B/W titles as well. This is obviously a place that gets a lot of traffic -- just seldom viewed while playing...

Hopefully he will address this in the future and hopefully each pf won't require a unique design....

They're on ebay! When I got my blades they sent the whole kit.
ebay.com link: itm

The protector you linked protects the wrong side (although I agree it should protect the front and back, not just the back). The picture the op posted shows damage on the front side of the hole where the ball drops into the hole, not the back side that the protector goes on. Unless of course I am missing something.

Does the ball actually hit the front of the hole? Maybe it's just over kill.

Those outholes (folks- this is the ONLY outhole on a modern era game, btw do get damaged from rattling balls bouncing back against the wood edge. But there are two problems protecting the edge.
#1, the potential for a really slow ball hanging on the edge of the protector. This is why I don't like making any protectors that face uphill. 90% of the time this wouldn't be an issue but then there's that other 10%
#2 mounting would be a booger because with Sterns and many WPC Williams/Bally the ball trough itself clamps up flush to the playfield. Squeezing my spring tab between it would likely cause a lifted edge which would make problem #1 even worse
Until I nail this problem I recommend a strip of 2mil mylar.

Merry Christmas fellow Pinsiders!

Mylar seems to be like Duck Tape for pinball machines.

The protector in the link from 2RustyBalls is a good start. It should go all the way round to the other side though. As it's rigid enough, there is no need to fix it on the upper side. Just need to make sure the edge doesn't come above the edge of the playfield when putting it in place. This way it will protect the inside of the outhole without interfering with any ball going in.