We’ve recently added a new pinning worksheet to the Pinning and Decoding Worksheets page in the Tools section. Under the SFIC tab, you will find two files named “One Page SFIC Pinning Chart”. This chart allows you to put together the entire pinning chart for a 7 pin SFIC master key system on a single page. Sounds too good to be true? It isn’t.

How it Works

This sort of pinning chart has been around for many decades but I’ve never seen it in a digital format. We sought to change that by making available in PDF and Excel formats.

To generate this pinning chart, you simply have to input your TMK and Control key bitting information. From there, you list your 4 progressives for each chamber and then use accepted SFIC formulas to determine your pin segments. Once fully generated, you move from box to box, matching the change key bittings, to successfully pin a core.

Let’s do a walk through to illustrate how it’s done. Here is a simple system I have put together:

As you can see, I have listed all possible progressives (green) for the TMK bitting (blue). Each box for each progressive contains the bottom, master, and build-up pins. Since all possible progressives will share the same top pin, the appropriate top pin is listed above each chamber’s column. With this chart completed, I just have to find the appropriate bitting for the appropriate chamber to determine my appropriate pinning. For example, if I need to pin a core to a change key bitting 1-4-7-7-5-8-1, I simply have to navigate as follows:

In the first chamber, I find the box for the 1 bitting and pin according to it. For the second chamber, I find the box for the 4 bitting and pin according to it. This goes on until I have pinned all 7 chambers. It’s that simple.

We have color coordinated specific areas of the Excel file to make it easier to navigated. Control key bittings are displayed in red, TMK bittings in blue, and progressive bittings as green. Additionally, we have included an area at the bottom of the page to keep constant pin stacks separate from progressed pin stacks to avoid any confusion.


There are few, powerful benefits. As stated earlier, you can generate an entire pinning chart for an entire system, save for special circumstances, on a single page. This allows you to save tremendous space in your truck and/or master key file(s). Second, it saves on time. If you generate this entire pinning chart immediately after creating the master key system, it’ll be the only time you’ll ever need to create a pinning chart for that system, again, save for special circumstances.