aloa.org October 2024 Keynotes 55 island. And I’ve walked from one side of the island to the other … but I digress. All the buildings are on the BEST A4 system — except one. Some clown who came before me decided to handwrite an A2 system for five floors in that building. Handwritten, when I’ve got loose-leaf books with BEST-provided bitting lists for every other building. Before I go further, if you’re new to the trade and aren’t familiar with BEST interchangeable cores, here’s some infor- mation to help you understand how it works. There are three different keying bitting systems: A2 and A4, as I men- tioned before, and A3. A2 has bottom pins from 0 to 9, top pins from 2 to 19, uses increments of 2, and each pin stack must equal 23. Figure 11 is an after-mar- ket A2 pinning kit made by LAB. BEST designates A2 bottom pins as 0A, 1A, etc. Top pins are designated 0B, 1B, etc. A4 has bottom pins from 0 to 5, top pins from 1 to 10 and uses increments of 1. Each pin stack adds up to 14. The bottom pins are designated 0E, 1E, etc. Top pins are 1F, 2F and so on. Figure 12 shows a genuine BEST A4 kit. Inciden- tally, older BEST pin kits were made of wood. I’ve never used A3, but I know it is being used in different parts of the country. I do have one of the wooden A3 kits. When I say increments, I’m referring to master keying within the systems. A2 has a lot of top pins, and they are smaller in height than A4 pins. This means that if you were progressing a pin chamber, it would be something like this: 2, 4. 6, 8. A4 would progress 1, 2, 3 and so on. But back to the “clown” I was talking about. The A2 system he conjured up has combinations in which he used a 0 cut next to a 9 cut, and sometimes more than once on each key. To be clear, there is no maximum adjacent cut specification (MACS) for any BEST keying system, but excessive use of the deepest cuts on any type of key weakens it. Figure 13 shows an extreme example of what I’m talking about and would probably never be an actual working key. From tip to bow, as BEST keys are cut, you see this combination: 9-0-9-0-9-0- 9. Look closely at the 0s; There’s hardly anything there. Just because you can use 0s next to 9s doesn’t mean you should. Getting a Handle on It Figures 14 and 15 are shots of the handle of a 70-year-old aluminum door. This is on the building I grew up in in Jersey City. My father was the superintendent of a 36-family building. Recently, I got a call that the handle was so loose it was about to fall off. I knew that the handle might disappear if it did, but it would also make it nearly impossible to open the door from the outside. FIGURES 14 AND 15. The handle was loose on this 70-year-old aluminum door. FIGURE 14 FIGURE 15
