Schlage Paracentric / numbered(e.g. 1347) keyways explained

[WOT]

You might have come across a Schlage keyway with four numbers. I finally figured out the nomenclature, so here it is. I'm sharing this in a hope to help fellows read Schlage paracentric keys by eye.

I photographed a key blank, then colored in the outline, so the drawing looks lame, but it's dimensionally accurate.

The blue sections denote common parts shared by all Schlage paracentric keys. The green part is the base center.

Thumb side is odds, finger side is evens.

Schlage paracentric keys are always expressed in a four digit number, in ascending order and you can have up to four ribs on any given blank.

The photo used to sketch this was a SC 1347. It means 1,3,4 and 7 are filled in and the numbers are always in an ascending order.

If positions 4, 2, 6 and 1 were filled in, it would be called SC 1246.

If there are less than four ribs, the ribs are expressed in ascending order, then the missing ribs are expressed as zeroes. Keys with zeroes are typically master blanks.

A key numbered SC3500 would enter any keyway designed to take keys containing 3 and 5. A keyway SC1200 means it would accept SC1000, SC2000, and SC1200.

Not counting the partially ribbed keys, it's theoretically possible to have 70 different profiles.

[unbreakable]

Interesting, thanks

[Trip Doctor]

Interesting, thanks

Agreed

[MBI]

That’s handy information, thanks for sharing it.

Do you know if they make an SC0000 key blank which would fit into all of them?

Also, do you have any idea if this numbering system relates to the SC20 key blank? I’ve heard it called Schlage’s “Universal” or “Skeleton” keyblank. Basically it’s a thinned down blank which can enter at least a dozen different Schlage keyways. Here’s a pic of the profile I’m talking about, it may not be exact, but it’s pretty close:

[Jaakko]

Very nice and informative text plus picture! Thank you very much for this Also it is somewhat funny that in the picture the fixed part of the keyway is in the shape of a letter S(chlage)

Thumb side is odds, finger side is evens.

Now I have to ask, is this an assumption or a saying? Lefthanded reporting for duty

[WOT]

That’s handy information, thanks for sharing it.

Do you know if they make an SC0000 key blank which would fit into all of them?

I know that SC 3578 exist, but not available from Ilco. That said, SC0000 may very well exist. The paracentric is pretty much obsolete and Schlage doesn't build a new system on it.
http://everestprimus.schlage.com/essent ... keyway.htm

Also, do you have any idea if this numbering system relates to the SC20 key blank? I’ve heard it called Schlage’s “Universal” or “Skeleton” keyblank. Basically it’s a thinned down blank which can enter at least a dozen different Schlage keyways.

It belongs to a different family. It belongs in the Obverse sub-group of Schlage classic. They're open keyways, meaning not restricted in anyway by Schlage. Paracentric keyways are only restricted in that Schlage decides who to sell and who to not sell.

The L blanks are usually used as the top level master in master keyed facilities, and institutional buildings often have hardware that uses the key as the knob or the thumb wheel, using the key to transfer the full force to retract the latch and these hardware are particularly hard on keys.

Master keyed system owners get their L TMK on special stainless steel blanks made at factory. These are stronger, but they wear out the locks.

Brass ones aren't hard on locks, but the key will break soon or later with regular use.

The L section just isn't ideal for every day use.

[mh]

Very nice post!

I just wonder why they call it 'paracentric' - it seems to be quite straight in the upper part?
That's what I would call paracentric:
http://www.ces-cylinder.de/_nexus/index ... te&page=47

Cheers,
mh

[Raymond]

I did not stop to look this up but I believe the term "paracentric" refers to any keyway in which the wards defining the key blank cross the vertical centerline of the keyway.

The term for those Schlage blanks might be "sectional."

[WOT]

That’s handy information, thanks for sharing it.

Do you know if they make an SC0000 key blank which would fit into all of them?

Since it's these forums, this is not an unreasonable solution.. AHEM...



You don't need that many TMK blanks,so the extra process shouldn't be much of a burden.

[wry415]

AWESOME post ... I've been playing with Schlage numbered keyway cylinders (my school campus uses 1247, and my employer uses 1456) for a few years, and I suspected there was a pattern between the numerical digits and corresponding milling, but I figured I'd need to see all of the keysections (or more of them, anyhow) to get the system.

Thanks for posting this!

... btw, most of the Schlage Numbered blanks aren't too difficult to find. The ones made by Ilco (SC1246, SC1247, SC1248, SC1345, SC1347, SC1348, SC1368, SC1400, SC1456, SC1460, SC1467, and SC1468) can be found on several keyblank sales-themed websites. Many of the remaining keysections not made by Ilco are made by Schlage (where the part numbers follow the pattern "35-101 XXXX" are a little less common, but I've found a few sites selling them.

[misterj]

That’s handy information, thanks for sharing it.

Do you know if they make an SC0000 key blank which would fit into all of them?

I know that SC 3578 exist, but not available from Ilco. That said, SC0000 may very well exist. The paracentric is pretty much obsolete and Schlage doesn't build a new system on it.
http://everestprimus.schlage.com/essent ... keyway.htm

Also, do you have any idea if this numbering system relates to the SC20 key blank? I’ve heard it called Schlage’s “Universal” or “Skeleton” keyblank. Basically it’s a thinned down blank which can enter at least a dozen different Schlage keyways.

It belongs to a different family. It belongs in the Obverse sub-group of Schlage classic. They're open keyways, meaning not restricted in anyway by Schlage. Paracentric keyways are only restricted in that Schlage decides who to sell and who to not sell.

The L blanks are usually used as the top level master in master keyed facilities, and institutional buildings often have hardware that uses the key as the knob or the thumb wheel, using the key to transfer the full force to retract the latch and these hardware are particularly hard on keys.

Master keyed system owners get their L TMK on special stainless steel blanks made at factory. These are stronger, but they wear out the locks.

Brass ones aren't hard on locks, but the key will break soon or later with regular use.

The L section just isn't ideal for every day use.

Not unlike classic Primus keys. One of the buildings I work in uses Primus on the exterior and classic on the interior (E keyway, so the Primus key is an EP). I have a grandmaster Primus that fits everything outside and in. The key is used to throw the latch on all doors, too...it's also hard on the key when used to unlock the Von Duprin exit bars. Most of the staff just have conventional interior blanks, but the few of us who are privy to a Primus master tend to go through them. The key is almost razor thin where the side milling is...and they have relatively short life spans when used around 100 times each day!

AWESOME post ... I've been playing with Schlage numbered keyway cylinders (my school campus uses 1247, and my employer uses 1456) for a few years, and I suspected there was a pattern between the numerical digits and corresponding milling, but I figured I'd need to see all of the keysections (or more of them, anyhow) to get the system.

Thanks for posting this!

... btw, most of the Schlage Numbered blanks aren't too difficult to find. The ones made by Ilco (SC1246, SC1247, SC1248, SC1345, SC1347, SC1348, SC1368, SC1400, SC1456, SC1460, SC1467, and SC1468) can be found on several keyblank sales-themed websites. Many of the remaining keysections not made by Ilco are made by Schlage (where the part numbers follow the pattern "35-101 XXXX" are a little less common, but I've found a few sites selling them.

I've never run across one in the wild before. Actually, the only building I've seen around here that uses Schlage at all is that building I work in. Interesting, because their prices aren't too bad in comparison to plenty of other manufacturers and I think the Everest / Everest Primus line is a pretty decent product. I run Everest C145 on my house. If I could get ahold of Everest Primus or even Primus classic stuff easier, I'd probably run that.