Small Format Vs. Large Format IC

[keysman]

A short while back there was a question about Small format IC verses large Format IC .. I finally got my camera back and had a little time to put this together.

There are other manufacturers of small and large format ICs then what is shown but this will show the general differences

These 2 pictures show the size difference between SFIC and LFIC as you can see the large format is bigger than the best style small format.








In the Small Format IC (SFIC) there are 2 major differences ... the individual chambers are capped on the “Best style " and the entire locks is capped by 1 piece for the Falcon Style





When the control key (removal key) is used in SFIC it moves a lug and allows the core to be removed.







For the Large Format the Design is a little different, the core is held in the lock by a small pin that moves with the correct key (Control Key)





Additionally Schalge Large format IC require a special key, to remove the core





The longer key actually raises a 7th pin to engage the control lug.






Below is an engineers drawing of the Schlage LFIC courtesy of Ingersol Rand Corp

[WOT]

Is the control blank actually longer than 35-101 6-pin or is it a matter of cutting a notch in the tip to make it a control blank?

[bumber]

Is the control blank actually longer than 35-101 6-pin or is it a matter of cutting a notch in the tip to make it a control blank?

Im pretty sure they are a 7pin key cut with a control key cut...

[keysman]

Is the control blank actually longer than 35-101 6-pin or is it a matter of cutting a notch in the tip to make it a control blank?

Yes , it doesn't show up well in the photo because of the shooting angle, but control key is actually a 1/2 cut longer.
You could make a control key by filing back the shoulders on a standard 6 pin blank.

[maintenanceguy]

I work with a lot of yale LFIC cores. very similar to the schlage. The little pin that locks the cylinder in place is slightly different but the theory is the same. Any working key, if cut on a 7 pin blank instead of the 6 pin blank will remove the core because it will lift the 7th pin.

I've tried removing the shoulder in a pinch and it did not work, the key's milling didn't extend far enough past the shoulder to let the key go into the cylinder far enough.

[Abus]

I've never really handled much by the way of Large format IC, other than Sargent dimple key so a couple dumb questions:

A. It looks to me, at least on the schlage, as if you can even with a conventional tension wrench pick the entire thing to the control shear as long as you lift the control pin before rotating the cylinder very much?

B. It looks to me that the control lug is actually operated by the pin sticking up out of the plug when lifted by the tip of the key, but I don't see how the control lug is locked when the control key isn't in position. Is there actually a top pin and spring in the body of the control lug that locks the control lug?

C. Is there a full range of possible control lug cut depths, or are the all the same? If there's a full range, can it be impressioned?

[keysman]

I've never really handled much by the way of Large format IC, other than Sargent dimple key so a couple dumb questions:

A. It looks to me, at least on the schlage, as if you can even with a conventional tension wrench pick the entire thing to the control shear as long as you lift the control pin before rotating the cylinder very much?

yes you couldn't move it much but , you have the right idea

B. It looks to me that the control lug is actually operated by the pin sticking up out of the plug when lifted by the tip of the key, but I don't see how the control lug is locked when the control key isn't in position. Is there actually a top pin and spring in the body of the control lug that locks the control lug?

In the picture "Schlage LFIC in locked position "you can see the 2 parts of the pins .. the control lug is spring loaded and in the locked position unless actually moved by the pin/ contol key.

C. Is there a full range of possible control lug cut depths, or are the all the same? If there's a full range, can it be impressioned?

No , the control cut on schlage LFIC is a # 6 always as far as I know

[WOT]

hmmm I suppose it's plausible to extend the tip with a Schledge hammer, no I meant sledge hammer. Grind off the area that gets too wide, then fix up the millings a bit with a Dremel.

[maintenanceguy]

I've never really handled much by the way of Large format IC, other than Sargent dimple key so a couple dumb questions:

A. It looks to me, at least on the schlage, as if you can even with a conventional tension wrench pick the entire thing to the control shear as long as you lift the control pin before rotating the cylinder very much?

B. It looks to me that the control lug is actually operated by the pin sticking up out of the plug when lifted by the tip of the key, but I don't see how the control lug is locked when the control key isn't in position. Is there actually a top pin and spring in the body of the control lug that locks the control lug?

C. Is there a full range of possible control lug cut depths, or are the all the same? If there's a full range, can it be impressioned?

A) Yes, you can pick it just like a regular lock cylinder. There is no shear line. If the last pin (the control pin) is lifted, turning the cylinder pulls in the control lug. If the last pin is not lifted, turning the cylinder just turns the cylinder.

B) The control lug is not locked in the "Sticking out" position. It could be pushed in if you could find a way to get to it. I don't know how you could though.

C) There is only one control pin depth. In fact, as long as the last pin (no top pin) is lifted high enough to engage the control lug, it will work so lots of cut depth would work but the one that's used is just a zero cut.

And you are right, if you pick this and rotate th plug a tiny, tiny amount you can then lift the last pin and engage the control lug. I learned in college that if you cut a 7 pin key blank almost all the way down (Like cut to 11) except for the very end and use that key as your tension wrench, you can remove an LFIC cylinder.

[Abus]

[quote="keysman"][quote="Abus"]

In the picture "Schlage LFIC in locked position "you can see the 2 parts of the pins .. the control lug is spring loaded and in the locked position unless actually moved by the pin/ contol key.


From the pictures, I have a hard time seeing exactly how the lug is spring loaded. If you press it in, on a cylinder w/o a key in it, does it move against an internal spring? Or does it have a spring detent sort of system that holds it in position so that pressing it "clicks" it in? Seems to raise some vulnerability issues if the lug is spring loaded with a relatively weak spring.

[keysman]

From the pictures, I have a hard time seeing exactly how the lug is spring loaded. If you press it in, on a cylinder w/o a key in it, does it move against an internal spring? Or does it have a spring detent sort of system that holds it in position so that pressing it "clicks" it in? Seems to raise some vulnerability issues if the lug is spring loaded with a relatively weak spring.

Give me a couple of days and I will take some more detailed pictures and try to give a better explaination of what is going on

[squelchtone]

keysman,

great pics and write up!


Thank You!

Squelchtone