So lets make a key blank:-
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A bit of good steel from my scrap box....
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Became this, as you can tell I rather like old style keys.
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And it fits the lock like a glove.

Now for the tricky bit, this is an eight lever lock, with a guard. So first to make a perspex shield that matches the cover plate and holds the key in its normal position. Thus enabling cutting for the throw bolt and each subsequent lever plate.
This is the lock in all its glory:-
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Name:	07 lock disassembled.JPG 
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Now to start cutting the blank to work, one step at a time. To this end you will see the perspex lid, with a brass 2BA screw in it, this is to ensure the lever and the followings ones do not lift whilst this progresses. The photo below shows all eight in position and it works beautifully.
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Finally one photo of it ready to be assembled
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Again there is a bit more to follow. Enjoy, Steve.