Welcome aboard Rico.
Rippling is probably something else, but the fuel cell can still expand and put pressure on the skins enough to cause cracks at weak points. Happened to my Multi1200 after two years.
I agree that rippling is probably something else, and I doubt that an expanding tank (have there been any reports of this on newer Monsters?) can exert sufficient pressure to cause cracking. I dunno about Multis, but on the newer Monsters there's enough... ahem.. movement and expansion space between tank and skins to prevent that IMO. I hope
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