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Locksmith Training | Rim, Mortise, Key-In-Knob Cylinders - Drilled 6, Pinned 5?

Be an on-call locksmith by mastering the fundamentals and basics of locksmithing. Now, as you work on commercial hardware, at some point, you have to start ordering replacement cylinders. And the technical term that gets brought up a lot, whether you're trying to purchase a rim cylinder, a mortise cylinder, or a key-in-knob cylinder, is drilled six pinned five. Let me show you what that means.

With these replacement cylinders, we'll go over all of them together. Let's have each box and talk about it.

replacement lock cylinders - locksmith supplies

The first one is the R118. It tells us it's a rim cylinder with an inch and an eight of length. SC for Schlage, and SC1 or SC4 keyway. 10B is the finish, then bronze, and then the A2 at the end means they're keyed alike in pairs. Meaning I had to rip a piece of tape off to grab one because they come in two.

R118 Replacement Cylinder

The mortise cylinder, like the M118, is also an inch and an eight.

M118 Mortise Cylinder

This cylinder comes with an SC1 key, a five-pin key, that you can make into a six-pin.

SC1 key, a five-pin key

And the key and knob cylinders. These are all going to be drilled with six pins and keyed five.

six pins keyed 5


You buy the M118 SC mortise cylinder, and then you need to pin it up to a six-pin key, the SC4 key. That means that we need to add a top pin and spring.

Here's how you do that.

Grab the K001 cylinder, a popular cylinder, and it's going to come with the Schlage C five-pin key, the SC1. Now, let's say we need to key it up to the SC4.

K001 cylinder

All we have to do is take off the back. Set the little pieces aside and spring.

Insert the key in and turn it.  Grab the follower and take it out.

Locksmith supplies - K001 cylinder

Open the very back, and you're going to see there's this sixth hole.

Using a key follower

And if you want to pin it up to an SC4 key or a six-pin, all you have to do is grab the tweezers and get the spring you set aside a while ago.

Working with a mortise cylinder

And then grab the top pin and put it in. There we go.

Drilled 6, Pinned 5

Now, on the actual plug, you can see it's going to come with five pins in it because this was a five-pin key drilled six pins pinned five.

locksmith training

And all we have to do now is take our SC4 key and stick it in, we'd key it up, and there'd be a spot right here for that six pins.

Drilled 6, Pinned 5

So that's what drilled six pinned five means; it means it's going to come with a five-pin key, and it's going to come pin to a five-pin key. So if you need to convert it to a six-pin like in this case, SC1 to SC4. Just make sure you add the spring and the top pin in the back of the cylinder, and then you'll be ready to go. Thank you, guys, for your time. I hope it was helpful and see you next time!

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