Gas Out - The Bane of All Coaters

[Toefuzz]

I know many of you, like me, constantly fight the evils of gas out and are unable to prove to your customer that gas out does in fact exist. I recently picked up a new toy and thought I'd share a picture I took that should pretty much end all arguments about gas out being nothing more than a coater's favorite excuse.

Needless to say I've been spending the past few days in front of my new baby (the microscope) and am having a blast learning to differentiate between gas out, dirt, seeds, etc, with degree of confidence previously unthinkable.

A little background on the pic... You're looking at a zinc diecasting, coated with a super durable poly at 390 for approximately 15 minutes. The part had been gassed out for more than 2 hours, 50 degrees higher than cure prior to being coated. The defect initially looked like a small lump of something, though the sharp edges suggested gas out. After lancing the top of the defect off I revealed what looks like swiss cheese... Ain't technology grand?!?


This is your coating... this is your coating on a crappy casting... any questions?

Thought/comments?