Junkunc AM1 keymaking

[Peter Martin]

I have an old American Junkunc Bros. padlock (the slab-sided steel circular version).
I have an AM1 key blank and removed the core from the lock.
The blank does NOT fit into the core--at least not while the wafers are in place.

So... I presume the holes in the wafer tumblers are not large enough to pass the key blank--at least not until the key is cut.

But then... how does one cut a key for this?

A pic of the core is included. Do I need to disassemble this farther? If so, how? I marked the spring location with a red arrow.

Pete
Sioux Falls, SD

[Raymond]

You are correct. The width of the blank after the cut on the key is the same for all wafers. What changes is where across the blank the cut is from side to side.

You can do it the hard way and remove all but the last pair of wafers, and while holding them flush with the shear line, cut the blank exactly in line with the inner hole on the wafers, on both sides of the blank. Then remove the first pair, add the next to last set of wafers, and cut those cuts without messing up the first cuts.

The easier way is to remove the spring. Cut one side of a blank all the way down to the base of the blade. Now the blank should slide in. The wafers will be pushed up on only one side. Carefully cut the blank down until the wafers all sit exactly flush on the shear line. Then prepare a second blank cutting off the blade on the opposite side from the first. Cut those wafers down in the same manner as the first blank. Now duplicate both halves onto a new blank. The final cut key should be almost perfect. You might have to make a few small cuts mainly where the key moves from one pair of wafers to another to provide sufficient clearance.

This method can also work on Illinois, Duo,and Chicago.