Hi. Welcome to Just Answer.
The catch needs to be pressed in to allow the plate to spin to be removed. Please see the edited picture below.
The green arrow points to what I believe is the assembly locking nut. This may have to be removed to take the lock out of the door.
If all else fails I watched a friend of mine remove a broken off key by spot welding a piece of brass rod to the end of the key. He had a home made device made from an old microwave transformer that he modified to be the power source for the spot welder.
I can contact him and ask how he made it if you like. The second drawing shows basically how he did it.
Thanks! You were right about the locking nut--that's what it took.
Thanks for the spot welding idea, too. I see it as a bit chancy (could spot-weld the key to the lock as easily as the rod to the key, I bet!) but I will definitely consider it.
So, I have the lockset out of the door and on the bench, but I'm not out of the woods yet. I'm trying to get the cylinder out, so I can either bang on it to "shake" the key out, or perhaps drill it from the inside end and push the key out (both tips from others), but, as I understand this, the knob/lever release---the one you normally push in with a small screw driver or awl, won't work unless you rotate the key 90 degrees (this makes it harder for a thief to get at the lock. I can't rotate the key, because it's broken off! Any suggestions? Is there any other way to get this sucker off or *must* that key be turned?
The key is hopefully in the right position to set the pins to the break point. If it is then all you need to do is turn the tumbler by inserting a small screw driver in it and twisting.
If you are not so lucky try pushing the key in a bit further....CAREFULLY and slowly...bit by bit, and keep trying the screwdriver. If you can position whats left of the key it should open the lock.
Failing that you have two options. Drill from the back and push it out, or drill from the front and take out the tumbler completely, or at least enough of it to remove the pins and then turn the tumbler with a tapered bolt or easy out.
Usually when I run into this I just drill the tumbler with a very sharp drill about 2 sizes smaller than the tumbler. I can then pick out the lock pins and turn the lock with an ez out.
Of course you then have to replace the tumbler and pins, but its cheaper than a locksmith and cheaper than a whole new lock. When I worked as a maintenance man for a 300 room motel in northern California I had a complete lock pin set and plenty of spare tumblers. On average some idiot would deliberatly stuff something into a lock and Id have to drill it just to let the maids into the room. Got to where I could do one in about 20 minuets. Rekeyed and all.
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