http://www.antique-padlocks.com/shared/napec_dcp_1381_01.pdf
Onward to the lock. It is a heavy chunk of stainless about 3 pounds 5 ounces. It's about 2.5 inches wide, 1.5 inches deep, and 3.75 inches tall. The shackle is 0.5 inches think.
This is bicentric lock, having two keyways. And it is dual custody, meaning that you have to have two keys to open it. Two different keys both at the same time have to be inserted and turned for it to open. One key alone will not open this lock.
Following the techdata sheet's instructions, the first thing I do is knock the retaining roll pin out with a 3/32'nds inch punch. No need to punch it all the way out. Just enough so that the top plate is clear to slide.
Next you have to unlock both the cores to release the shackle. This will allow the top plate to slide when the shackle is lifted all the way up to clear the bottom case.
The two halves of the lock slide together in a very nice dove-tail arrangement.
Here is the top removed and the shackle dropped back down to where it would be in the locking position. You can see there is a roll pin at the heel of the shackle so it won't come out of the top plate.
Next, looking down into the body of the lock. These are the massive locking bars. They are in the locked position.
Here you can see I unlocked the left locking bar. This lock requires two keys to open, if you only undo one of the cylinders the other other bar is not letting the hasp go anywhere. Safe to say this lock is a bit un-shimmable too.
Locking bars taken out. They are really quite substantial pieces of metal.
Empty case. Fun fact: this empty body weighs exactly the same as the topslide, hasp, cylinders, and locking bars all added together.
Top slide turned upside down. Locking bars in the locked position.
And the unlocked position.
Well, I think that's it. Pretty simple on the inside but it really gets the job done. This lock is fairly rare and I feel very very fortunate to have it in my collection. Let me know if you have any questions.
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