I finally got my gremlins worked out and now my key won't turn the ignition lock cylinder. It was working fine up until a few days ago. It slowly got more and more finicky with each start until it would not turn at all.

I figured it was the tumblers hanging up so I quirted some lube in there and taped it with a mallet, still no luck. Inspected my keys, nothing is broken on any of them.

Any other tricks out there before I have to bring it to a locksmith?