This isn't meant to talk down to you in any way, I just don't know how else to phrase it, but... Are you sure you have the air chisel set up right? I added a quick release to mine that threads onto the end of the gun. It has set screws around the edges to prevent it from backing out but, they're useless. If it even backs out a 1/8 turn, I lose all cutting power. It still makes the same sounds as if it's working as its meant to. I just can't get through rivets, even the aluminum ones. If I hadn't used one before I might not recognize there's a problem.
Some will have a "power" screw to adjust the gun's speed/force. If that gets out of whack, same deal. Might be something to look at.
Pictures might help us or even a short video clip. I'm wondering if you don't have some solid rivets in there or if your chisel/technique is off or...?
-Travis & the DawgBüs
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