see that the side electrode is not square but kind of beveled above the center electrode
Exactly. But that's magnified. So you have to look at the metal to surface loss ratio. There is no way that each spark is going to pound a bevel off that, blow a chunk into a ball, no fucking way. Go back where I said it takes 1000's of hits to cause that, so you do the math times mileage, stopping, idling, etc. It adds up, but we are talking about it vaporizing when it does bite off a molecule or count how many are blasted off that, then look at a plug with low mileage and you can't even see a spec on the porcelain.
No, when we discuss those balls, to my experience, that says 'molten&many.' And those are large in proportion to the bevel around the center electrode. Not only that, it would have to be consistent and continue to eat away at the center and side electrodes, "equally."
I also noticed that bevel on the new plug: if where I think you mean? So imagine I cutout that side electrode so a pocket is formed. What lays in that pocket? More fuel to start the ignition to begin the 'flame front.' Flat side electrode is a wax thick kind of fuel layer. So that troth of liquid/air is also a consistent starter place too if you think about it.
We talking about the same pocket? I say machined away, you say the spark ate it away? I say rub both hands together and that means both contact points were equally eaten away. Your troth is way out of proportion of being equal in electrical eatery. Something huge had to ball up like that. And carbon does not ball on every fire. That is layer after layer covering the chamber over the next layer. Show me the ball in that.
And Grn, run dry plugs. Don't worry. Book is not.
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