Quoted from palacekeeper: It almost seems like it gets a little hung up at the base of the diverter, but it always makes it past it, so I'm not sure what to make of that.
Would that mean it's too far from the wall and needs to be a mm or two closer?
It sounds to me like the ball is struggling to get up the arm. The base of the diverter is a pinch point which is why you are pulling the ramp out, at least that's how I interpreted it. I have mine pulled out enough that I could stick a 1" rubber behind the left side of the ramp. So technically, you are only trying to pull out the left side of the ramp so that the ramp is closer to the base of the diverter arm, the right side of the ramp can remain flush. I think the ball needs to have more of the rod underneath the ball than on the side of it to create less of a pinch and produce less resistance as it ascends. Also note that you are limited to the amount you can move the ramp forward because when the diverter arm activates, the arm will run into the edge of the hole it is sticking through. The arm should barely touch the edge of that hole without impeding it's movement. Also make sure that the ball still rolls past the arm when not activated.
One more thing to note is the offset between the back of the ramp and the back plastic on the wall, now that the ramp is pulled out. Set the ball at the base of the diverter arm, activate the arm at the coil and use a screwdriver to roll the ball up the arm slowly to see how much the ball is affected by the offset. You want the ramp to be slightly more out in front of the back plastic so that the ball doesn't get hung up in that gap. If the ramp is to far out in front I think this can be problematic as well because you don't want the ball banging around as it moves over the offset. You can reduce the offset by removing the bottom left screw in the back plastic and sticking washers behind the plastic to move just the left side out.
Lastly, and you may already be doing this, I would definitely test the mech by pulling your playfield out to the rubber feet and rolling the ball up the ramp with the coil engaged by holding it in with your hand. You'll have to roll the ball with a little speed, but if your diverter arm is off, then you won't be able to make it up to the magnet. Once dialed in, the ball will make it all the way, nice and clean. Not only does it help to be standing right over the top of the mech while you're watching balls fly up, but I also think this "breaks in" your adjustments, so I would roll it up the arm 15-20 times before shooting it with the flippers.
Sorry for the lengthy post, but this is one the coolest shots in pinball and totally worth the effort. Hope this helps, don't give up!
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