Hello everybody,
Please feel free to correct any terminology that I did not get right, it is the only way to learn.
Took apart my Hi Shear and took some photos. I didn't take pics of how to take down etc.
Some info: The Hi Shear uses a Medeco 6 pin Classic cylinder. It uses the EXACT same one as in an 831b. The only differences are with the cuts on the operating keys to get it into the control position.
Front
Back
Keyway
First comes the components of the plug.
The anti drill disc (Called ADD from now). It kind of just sits in the bottom of the keyway and is held into place by the next piece, it does not attach to the cylinder in any way.
The piece that holds the ADD in. It spreads outward to create friction to stay in place.
This little piece is used to take up the extra space from the ADD and its retainer so that the cylinder sits even.
How it fits in:
Other side:
They all fit into the bottom. The ADD first, followed by the small metal part, then the silver retainer.
No spacer
With the spacer. The retainer is lifted a small amount to better see it.
The ball bearing serves dual purposes. It prevents the cylinder from just dropping out, and it also activates little rods that lock the plug into place.
Be careful, it just falls right out.
The locking bars
Taking them out. DONT PULL THEM! There is a little spring that you really dont want to extend. they both come out together.
Out
The bars. Notice how one is a little bigger than the other? That is because the hole where the bearing sits is slightly off center, so remember which side the bigger one was on.
With the bearing. When not in the control position, the cam pushes the bearing against the bars and that pushes them out into little slots where they lock the plug into place.
When in the control position, the cam turns and the bearing gets pushed into a small dimple allowing the spring to pull the bars and retract them into the plug allowing you to remove it.
The back of the cylinder and underside of the cam.
Fully assembled plug in neutral position. Notice the bars on the sides?
In the control position. The bars are gone, and the little gap between the cam and plug on the right side is gone:
In the unlocked position
The round pillar on the cam goes into the slot on the shackle, and the "flat rounded" part follows in the track on t he lower right.
Here is where those 2 rods go in the lock
And something I bet nobody has noticed before, there is a rod of some sort inserted into the middle of the shackle. The shackle spins freely to help prevent attack.
And in case anybody was curious, here are the pins:
Bottom pins:
1: ARX w/ false gate
2: ARX w/ false gate
3: ARX w/ false gate
4: ARX w/o false gate
5: Regular w/ false gate
6: ARX w/ false gate
Top pins are all regular except number 5. It is a modified mushroom pin. The bottom of it looks like a barrel pin.
And the key: The 5th cut is the highest, and also with the barrel/mushroom pin.
As a small afterthought: I was curious as to the holes on the bottom the first time I saw a Hi-shear.
1 standard S&G military chain (Borrowed from my 833):
+ a Hi Shear:
= An answered question
Enjoy
