Chubb safe with detector lock

[snow52]

Hi, i recently bought this safe and had the lock dated to 1856 and the safe to 1858/9. it has all been repainted but think i will try to do a better job myself, i found it has a detector on it, however the key would not operate the detector and now i have found why!

one of the teeth seems to have worn and Will not quite unlock the detector, here are some pics for you to study, the key is not original, or so im told. and although it has had a repair on the bow, it does have chubb's on it. i have had one before with the same repair. my feeling is that the safe had been tampered with and the owner was unaware it had a detector and so forcing the key round, who know's?

one of the pics is where the levers have been removed to show the stub not quite entering the gate, the others are for reference.